The document discusses different types of masks and respirators, their construction, materials, and standards. It describes face masks as having minimum requirements and not for medical use. Medical face masks are tested according to standards and intended to prevent transmission of particles/droplets. Respirators are designed to filter both solid particles and liquid droplets for personal protective equipment. They are subject to standards like EN 149 and have features like tight fitting and volume design for breathing. Modern masks and respirators use multilayer construction with layers serving purposes like outer protection, inner comfort, and electrostatic filtration.
This document discusses different types of protective face masks and gear. It defines masks as barriers that cover the nose and mouth to protect from airborne particles. The main types discussed are basic cloth masks, surgical masks, respirators like N95 masks, and full face shields. It provides details on what each type filters out and their proper use to protect wearers during the COVID-19 pandemic. Risks of improper use are also summarized.
This case report describes the use of a silicone implant for augmentation rhinoplasty in a 17.5-year-old male patient with a saddle nose deformity caused by a childhood nasal infection. A silicone implant was placed through an incision in the columella to reconstruct the nasal dorsum. The postoperative result showed good correction of the nasal deformity with no complications. The report discusses the advantages of silicone implants for augmentation rhinoplasty, including affordability, reduced risk of extrusion or infection compared to other implant materials, and the ability to provide adequate support and definition to correct mild to moderate nasal deformities.
Indian Dental Academy: will be one of the most relevant and exciting training center with best faculty and flexible training programs for dental professionals who wish to advance in their dental practice,Offers certified courses in Dental implants,Orthodontics,Endodontics,Cosmetic Dentistry, Prosthetic Dentistry, Periodontics and General Dentistry.
Conservative and pain free techniques in pediatric dentistryDrNadhem
The document discusses several minimally invasive and pain-free dental procedures for treating cavities in children. It describes techniques like Atraumatic Restorative Treatment (ART), Interim Therapeutic Restoration (ITR), air abrasion, air polishing, ozone therapy, chemomechanical caries removal, and lasers. These alternative methods aim to remove decay using hand instruments or chemical agents instead of drills, preserve tooth structure, and reduce pain and discomfort for children compared to traditional cavity preparation. The document provides details on the mechanisms, applications, advantages, and limitations of these conservative dental approaches.
Air abrasion is a new dental technology that can replace traditional drills in some situations like early tooth decay. It works by using compressed air to propel aluminum oxide particles that spray away decayed parts of the tooth without heat, sound, pressure or vibration. Some advantages over drills include reduced need for anesthesia, preserving more healthy tooth tissue, keeping the work area dry, and lower risk of cracking or chipping teeth.
Isolation techniques in pediatric dentistryAnuRaaga
This document discusses various isolation techniques used in pediatric dentistry. It describes the goals of isolation as moisture control, retraction, prevention of harm, and creating a safe operating field. Direct isolation methods mentioned include rubber dams, cotton rolls, evacuators, retraction cords, and mouth props. Indirect methods include patient positioning, local anesthesia, and anti-anxiety medications. The document provides details on the history and advantages of rubber dams, important components like sheets, clamps, and frames, as well as recent advances in isolation products.
Fluid control and soft tissue management / cosmetic dentistry trainingIndian dental academy
Indian Dental Academy: will be one of the most relevant and exciting
training center with best faculty and flexible training programs
for dental professionals who wish to advance in their dental
practice,Offers certified courses in Dental
implants,Orthodontics,Endodontics,Cosmetic Dentistry, Prosthetic
Dentistry, Periodontics and General Dentistry.
This document discusses different types of protective face masks and gear. It defines masks as barriers that cover the nose and mouth to protect from airborne particles. The main types discussed are basic cloth masks, surgical masks, respirators like N95 masks, and full face shields. It provides details on what each type filters out and their proper use to protect wearers during the COVID-19 pandemic. Risks of improper use are also summarized.
This case report describes the use of a silicone implant for augmentation rhinoplasty in a 17.5-year-old male patient with a saddle nose deformity caused by a childhood nasal infection. A silicone implant was placed through an incision in the columella to reconstruct the nasal dorsum. The postoperative result showed good correction of the nasal deformity with no complications. The report discusses the advantages of silicone implants for augmentation rhinoplasty, including affordability, reduced risk of extrusion or infection compared to other implant materials, and the ability to provide adequate support and definition to correct mild to moderate nasal deformities.
Indian Dental Academy: will be one of the most relevant and exciting training center with best faculty and flexible training programs for dental professionals who wish to advance in their dental practice,Offers certified courses in Dental implants,Orthodontics,Endodontics,Cosmetic Dentistry, Prosthetic Dentistry, Periodontics and General Dentistry.
Conservative and pain free techniques in pediatric dentistryDrNadhem
The document discusses several minimally invasive and pain-free dental procedures for treating cavities in children. It describes techniques like Atraumatic Restorative Treatment (ART), Interim Therapeutic Restoration (ITR), air abrasion, air polishing, ozone therapy, chemomechanical caries removal, and lasers. These alternative methods aim to remove decay using hand instruments or chemical agents instead of drills, preserve tooth structure, and reduce pain and discomfort for children compared to traditional cavity preparation. The document provides details on the mechanisms, applications, advantages, and limitations of these conservative dental approaches.
Air abrasion is a new dental technology that can replace traditional drills in some situations like early tooth decay. It works by using compressed air to propel aluminum oxide particles that spray away decayed parts of the tooth without heat, sound, pressure or vibration. Some advantages over drills include reduced need for anesthesia, preserving more healthy tooth tissue, keeping the work area dry, and lower risk of cracking or chipping teeth.
Isolation techniques in pediatric dentistryAnuRaaga
This document discusses various isolation techniques used in pediatric dentistry. It describes the goals of isolation as moisture control, retraction, prevention of harm, and creating a safe operating field. Direct isolation methods mentioned include rubber dams, cotton rolls, evacuators, retraction cords, and mouth props. Indirect methods include patient positioning, local anesthesia, and anti-anxiety medications. The document provides details on the history and advantages of rubber dams, important components like sheets, clamps, and frames, as well as recent advances in isolation products.
Fluid control and soft tissue management / cosmetic dentistry trainingIndian dental academy
Indian Dental Academy: will be one of the most relevant and exciting
training center with best faculty and flexible training programs
for dental professionals who wish to advance in their dental
practice,Offers certified courses in Dental
implants,Orthodontics,Endodontics,Cosmetic Dentistry, Prosthetic
Dentistry, Periodontics and General Dentistry.
This presentation discusses surgical gowns. Surgical gowns are worn by medical professionals during surgical procedures to prevent the transfer of microorganisms and protect both patients and staff. They must provide a barrier to microbes while also being resistant to liquids, abrasion, and tearing. Surgical gowns play a crucial role in maintaining asepsis in the operating room by reducing bacteria transfer from skin to air. Their purpose is to prevent bacteria from entering wounds and protect staff from bodily fluids. The presentation covers the importance of surgical gowns, types of materials used including both reusable and single-use options, and objectives to reduce infection risks.
Indian Dental Academy: will be one of the most relevant and exciting training center with best faculty and flexible training programs for dental professionals who wish to advance in their dental practice,Offers certified courses in Dental implants,Orthodontics,Endodontics,Cosmetic Dentistry, Prosthetic Dentistry, Periodontics and General Dentistry.
This document summarizes various surgical supplies including sutures, dressings, and other operating room supplies. It discusses the different types of instruments used for dissecting, holding, retracting, and suturing tissue. It also describes various primary and secondary wound dressings such as gauze, film dressings, and absorbents. Additionally, it outlines hemostatic products, disposable packs, masks and other operating room supplies. The document provides details on absorbable and non-absorbable sutures and ligatures as well as surgical needles. It discusses the role of pharmacists in advising on appropriate product selection and use.
Fluid control and soft tissue managementDr.Amrit Assi
This document discusses various methods for controlling fluids and soft tissues during restorative dental procedures. It describes the importance of fluid control for patient comfort, operator safety and access. Rubber dams, high-volume vacuums and saliva ejectors are discussed as fluid control methods. Methods for displacing gingival tissues are also covered, including the use of displacement cords, which can be impregnated with chemicals to aid retraction when placed in the sulcus. Proper technique for cord placement is described to minimize risk of damage to gingival tissues.
Fluid control and Soft tissue managementHarisankar KS
This document discusses fluid control and soft tissue management techniques used in dentistry. It describes various mechanical methods of fluid control like rubber dams, high volume suction, and cotton rolls. It also discusses chemical methods using anti-sialagogues and local anesthetics to control saliva. The document focuses on gingival retraction techniques, including non-surgical methods using retraction crowns, cords, and pastes as well as surgical methods. It provides details on different retraction cords and medicaments used to aid in gingival displacement and outlines common techniques for cord placement.
This document discusses methods for fluid control and gingival tissue management during dental impressions. It begins by outlining the objectives of fluid control and introduces mechanical and chemical methods. Mechanical methods discussed include rubber dam, suction devices, and cotton rolls. Chemical methods include anti-sialogogues and local anesthetics. The document then focuses on gingival retraction, comparing mechanical, mechano-chemical, and surgical techniques. It provides details on retraction cords, electrosurgery, and recent advances in retraction agents. Throughout, it emphasizes the importance of fluid control and gingival displacement for accurate dental impressions.
esthetic facial surgery (Blepharoplasty, Forehead & Brow Proceduresbhanupriya149
This document summarizes blepharoplasty and forehead/brow lift procedures. It begins with an overview of blepharoplasty, describing the anatomy of the eyelids and changes that occur with aging. Upper and lower blepharoplasty techniques are then explained in detail, including skin excision, fat removal, and closure methods. Risks such as hematoma, asymmetry, and lagophthalmos are reviewed. The document concludes by discussing forehead and brow lift anatomy and techniques like the coronal and anterior hairline approaches, which allow access to muscles like the corrugator for weakening. Surgical planning and exposure are emphasized to achieve natural, youthful results.
Noncarious lesions and their managementSaurav Paul
This document discusses the classification and management of noncarious lesions, including abrasion, erosion, attrition, and abfraction. It describes the etiology, clinical presentation, and treatment considerations for each condition. For treatment, the goal is to modify the etiologic factors and restore defects when they compromise tooth structure or function. Class V cervical lesions are typically restored with composites or resin-modified glass ionomers, with detailed preparation and restoration techniques provided.
This document discusses various methods for fluid control and soft tissue management during dental procedures. It describes the objectives of fluid control as removing fluids, isolating tissues, enhancing visibility and patient comfort. Methods discussed include rubber dams, absorbents, high vacuum suction, saliva ejectors, anti-sialogogues and local anesthetic. Gingival retraction techniques aim to displace gingiva and expose margins, including mechanical methods like rubber dams and cords, and mechanochemical methods using hemostatic and astringent chemicals impregnated in cords. Popular chemicals discussed are epinephrine, alum, aluminum chloride and ferric sulfate.
A quick document on what you need to know about face masks in response to the COVID-19 pandemic - how to use and maintain them, ways of preparing a mask at home, steps & precautions, and a little more useful information revolving around masks.
Fixed partial dentures require careful fluid and soft tissue management during tooth preparation and impressions. Isolation techniques like rubber dams, high volume suction, and saliva ejectors help control fluids and retract soft tissues for optimal visibility and material properties. Gingival retraction further exposes the finish line and can be achieved mechanically using copper bands or retraction cords, or chemically using vasoconstrictors impregnated in cords. Temporary restorations protect the teeth until final prostheses are fabricated.
Gingival retraction techniques for implants versus teeth/ cosmetic dentistry ...Indian dental academy
Indian Dental Academy: will be one of the most relevant and exciting
training center with best faculty and flexible training programs
for dental professionals who wish to advance in their dental
practice,Offers certified courses in Dental
implants,Orthodontics,Endodontics,Cosmetic Dentistry, Prosthetic
Dentistry, Periodontics and General Dentistry.
SUBGINGIVAL AIR-POLISHING WITHERYTHRITOL DURING PERIODONTALMAINTENANCE, JOU...Shilpa Shiv
This randomized clinical trial evaluated the effects of repeated subgingival air-polishing using an erythritol powder containing chlorhexidine, compared to ultrasonic instrumentation, during periodontal maintenance over 12 months. Fifty patients with residual pockets >4mm were randomly assigned to receive either air-polishing or ultrasonics on one side of their mouth at baseline and 3, 6, and 9 months. Clinical parameters including plaque, probing depth, bleeding, and recession were measured at baseline and 3, 6, 9, and 12 months. Subgingival plaque samples were also collected at various timepoints to analyze microbiological outcomes. The aim was to evaluate the long-term effects of repeated subgingival air-polishing using the
Complications of periodontal surgery /certified fixed orthodontic courses by...Indian dental academy
Welcome to Indian Dental Academy
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and offering a wide range of dental certified courses in different formats.
Indian dental academy has a unique training program & curriculum that provides students with exceptional clinical skills and enabling them to return to their office with high level confidence and start treating patients
State of the art comprehensive training-Faculty of world wide repute &Very affordable.
This document discusses various methods for fluid control in dentistry. It describes mechanical methods like rubber dams, high volume evacuators, saliva ejectors, cotton rolls and gauze. Chemical methods include using antisialogogue drugs and local anesthesia to reduce saliva. Retraction of gingival tissues can be done mechanically using copper bands, retraction cords or rubber dams, or chemically/surgically using vasoconstrictors, electrosurgery or gingival curettage. Proper technique is described for placement of retraction cords and use of electrosurgery. The objectives of fluid control are to provide a dry field, improve access and visibility, protect the patient, and increase
This document discusses different methods for soft tissue management and gingival retraction during dental procedures. It covers the use of retraction cords made of 100% cotton to retract gingiva and achieve hemostasis when soaked in a solution. Various sizes of retraction cords are recommended for different areas of the mouth. Hemostatic agents like aluminum chloride, aluminum sulfate, and ferric sulfate can be used with the cords. Newer retraction cords are designed to eliminate issues like time consumption, patient discomfort, and epithelial attachment damage by maintaining rigidity in the sulcus without needing pressure for application.
This document discusses techniques for fluid control and tissue management during fixed prosthodontic impressions. It begins by explaining the importance of fluid control to obtain an accurate impression and lists various methods for fluid control like retraction cords, cotton rolls, and suction. Next, it describes different types of retraction cords and instruments used to displace tissues and examines their purposes. It then provides details on the speaker's preferred technique using two different sized cords and hemostatic agents to minimize trauma during impression making. In summary, this document outlines best practices for fluid control and tissue retraction to obtain high quality fixed prosthodontic impressions.
The document discusses personal protective equipment (PPE) used in medical settings. It defines what PPE is and its purpose in protecting health by preventing the spread of infections. It then provides details on the common types of PPE - gloves, goggles, gowns, masks, shoe covers, and face shields. For each type of PPE, it outlines the materials used for manufacturing, relevant standards and specifications, and manufacturing processes. The document aims to educate on PPE for medical professionals during the COVID-19 pandemic.
Face mask and respirators are the major device which comes under both protective clothing and medical textiles. The design and development of such protective clothing is driven by the choice of materials, as defined by the social, psychological or physiological requirement of user, choice of technologies as defined by desired functionality and ergonomic considerations, assembly methods, sizing and fit. This paper specifically reviews the facemask and respirators with respect to right selection of mask functional, design and ergonomic requirements product development and its characteristics evaluation and test methods and few ongoing researches on filtration of nano sized particle. A. Muralikrishnan "Design and Development of Face Masks" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-6 | Issue-6 , October 2022, URL: https://www.ijtsrd.com/papers/ijtsrd51897.pdf Paper URL: https://www.ijtsrd.com/engineering/textile-engineering/51897/design-and-development-of-face-masks/a-muralikrishnan
This presentation discusses surgical gowns. Surgical gowns are worn by medical professionals during surgical procedures to prevent the transfer of microorganisms and protect both patients and staff. They must provide a barrier to microbes while also being resistant to liquids, abrasion, and tearing. Surgical gowns play a crucial role in maintaining asepsis in the operating room by reducing bacteria transfer from skin to air. Their purpose is to prevent bacteria from entering wounds and protect staff from bodily fluids. The presentation covers the importance of surgical gowns, types of materials used including both reusable and single-use options, and objectives to reduce infection risks.
Indian Dental Academy: will be one of the most relevant and exciting training center with best faculty and flexible training programs for dental professionals who wish to advance in their dental practice,Offers certified courses in Dental implants,Orthodontics,Endodontics,Cosmetic Dentistry, Prosthetic Dentistry, Periodontics and General Dentistry.
This document summarizes various surgical supplies including sutures, dressings, and other operating room supplies. It discusses the different types of instruments used for dissecting, holding, retracting, and suturing tissue. It also describes various primary and secondary wound dressings such as gauze, film dressings, and absorbents. Additionally, it outlines hemostatic products, disposable packs, masks and other operating room supplies. The document provides details on absorbable and non-absorbable sutures and ligatures as well as surgical needles. It discusses the role of pharmacists in advising on appropriate product selection and use.
Fluid control and soft tissue managementDr.Amrit Assi
This document discusses various methods for controlling fluids and soft tissues during restorative dental procedures. It describes the importance of fluid control for patient comfort, operator safety and access. Rubber dams, high-volume vacuums and saliva ejectors are discussed as fluid control methods. Methods for displacing gingival tissues are also covered, including the use of displacement cords, which can be impregnated with chemicals to aid retraction when placed in the sulcus. Proper technique for cord placement is described to minimize risk of damage to gingival tissues.
Fluid control and Soft tissue managementHarisankar KS
This document discusses fluid control and soft tissue management techniques used in dentistry. It describes various mechanical methods of fluid control like rubber dams, high volume suction, and cotton rolls. It also discusses chemical methods using anti-sialagogues and local anesthetics to control saliva. The document focuses on gingival retraction techniques, including non-surgical methods using retraction crowns, cords, and pastes as well as surgical methods. It provides details on different retraction cords and medicaments used to aid in gingival displacement and outlines common techniques for cord placement.
This document discusses methods for fluid control and gingival tissue management during dental impressions. It begins by outlining the objectives of fluid control and introduces mechanical and chemical methods. Mechanical methods discussed include rubber dam, suction devices, and cotton rolls. Chemical methods include anti-sialogogues and local anesthetics. The document then focuses on gingival retraction, comparing mechanical, mechano-chemical, and surgical techniques. It provides details on retraction cords, electrosurgery, and recent advances in retraction agents. Throughout, it emphasizes the importance of fluid control and gingival displacement for accurate dental impressions.
esthetic facial surgery (Blepharoplasty, Forehead & Brow Proceduresbhanupriya149
This document summarizes blepharoplasty and forehead/brow lift procedures. It begins with an overview of blepharoplasty, describing the anatomy of the eyelids and changes that occur with aging. Upper and lower blepharoplasty techniques are then explained in detail, including skin excision, fat removal, and closure methods. Risks such as hematoma, asymmetry, and lagophthalmos are reviewed. The document concludes by discussing forehead and brow lift anatomy and techniques like the coronal and anterior hairline approaches, which allow access to muscles like the corrugator for weakening. Surgical planning and exposure are emphasized to achieve natural, youthful results.
Noncarious lesions and their managementSaurav Paul
This document discusses the classification and management of noncarious lesions, including abrasion, erosion, attrition, and abfraction. It describes the etiology, clinical presentation, and treatment considerations for each condition. For treatment, the goal is to modify the etiologic factors and restore defects when they compromise tooth structure or function. Class V cervical lesions are typically restored with composites or resin-modified glass ionomers, with detailed preparation and restoration techniques provided.
This document discusses various methods for fluid control and soft tissue management during dental procedures. It describes the objectives of fluid control as removing fluids, isolating tissues, enhancing visibility and patient comfort. Methods discussed include rubber dams, absorbents, high vacuum suction, saliva ejectors, anti-sialogogues and local anesthetic. Gingival retraction techniques aim to displace gingiva and expose margins, including mechanical methods like rubber dams and cords, and mechanochemical methods using hemostatic and astringent chemicals impregnated in cords. Popular chemicals discussed are epinephrine, alum, aluminum chloride and ferric sulfate.
A quick document on what you need to know about face masks in response to the COVID-19 pandemic - how to use and maintain them, ways of preparing a mask at home, steps & precautions, and a little more useful information revolving around masks.
Fixed partial dentures require careful fluid and soft tissue management during tooth preparation and impressions. Isolation techniques like rubber dams, high volume suction, and saliva ejectors help control fluids and retract soft tissues for optimal visibility and material properties. Gingival retraction further exposes the finish line and can be achieved mechanically using copper bands or retraction cords, or chemically using vasoconstrictors impregnated in cords. Temporary restorations protect the teeth until final prostheses are fabricated.
Gingival retraction techniques for implants versus teeth/ cosmetic dentistry ...Indian dental academy
Indian Dental Academy: will be one of the most relevant and exciting
training center with best faculty and flexible training programs
for dental professionals who wish to advance in their dental
practice,Offers certified courses in Dental
implants,Orthodontics,Endodontics,Cosmetic Dentistry, Prosthetic
Dentistry, Periodontics and General Dentistry.
SUBGINGIVAL AIR-POLISHING WITHERYTHRITOL DURING PERIODONTALMAINTENANCE, JOU...Shilpa Shiv
This randomized clinical trial evaluated the effects of repeated subgingival air-polishing using an erythritol powder containing chlorhexidine, compared to ultrasonic instrumentation, during periodontal maintenance over 12 months. Fifty patients with residual pockets >4mm were randomly assigned to receive either air-polishing or ultrasonics on one side of their mouth at baseline and 3, 6, and 9 months. Clinical parameters including plaque, probing depth, bleeding, and recession were measured at baseline and 3, 6, 9, and 12 months. Subgingival plaque samples were also collected at various timepoints to analyze microbiological outcomes. The aim was to evaluate the long-term effects of repeated subgingival air-polishing using the
Complications of periodontal surgery /certified fixed orthodontic courses by...Indian dental academy
Welcome to Indian Dental Academy
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and offering a wide range of dental certified courses in different formats.
Indian dental academy has a unique training program & curriculum that provides students with exceptional clinical skills and enabling them to return to their office with high level confidence and start treating patients
State of the art comprehensive training-Faculty of world wide repute &Very affordable.
This document discusses various methods for fluid control in dentistry. It describes mechanical methods like rubber dams, high volume evacuators, saliva ejectors, cotton rolls and gauze. Chemical methods include using antisialogogue drugs and local anesthesia to reduce saliva. Retraction of gingival tissues can be done mechanically using copper bands, retraction cords or rubber dams, or chemically/surgically using vasoconstrictors, electrosurgery or gingival curettage. Proper technique is described for placement of retraction cords and use of electrosurgery. The objectives of fluid control are to provide a dry field, improve access and visibility, protect the patient, and increase
This document discusses different methods for soft tissue management and gingival retraction during dental procedures. It covers the use of retraction cords made of 100% cotton to retract gingiva and achieve hemostasis when soaked in a solution. Various sizes of retraction cords are recommended for different areas of the mouth. Hemostatic agents like aluminum chloride, aluminum sulfate, and ferric sulfate can be used with the cords. Newer retraction cords are designed to eliminate issues like time consumption, patient discomfort, and epithelial attachment damage by maintaining rigidity in the sulcus without needing pressure for application.
This document discusses techniques for fluid control and tissue management during fixed prosthodontic impressions. It begins by explaining the importance of fluid control to obtain an accurate impression and lists various methods for fluid control like retraction cords, cotton rolls, and suction. Next, it describes different types of retraction cords and instruments used to displace tissues and examines their purposes. It then provides details on the speaker's preferred technique using two different sized cords and hemostatic agents to minimize trauma during impression making. In summary, this document outlines best practices for fluid control and tissue retraction to obtain high quality fixed prosthodontic impressions.
The document discusses personal protective equipment (PPE) used in medical settings. It defines what PPE is and its purpose in protecting health by preventing the spread of infections. It then provides details on the common types of PPE - gloves, goggles, gowns, masks, shoe covers, and face shields. For each type of PPE, it outlines the materials used for manufacturing, relevant standards and specifications, and manufacturing processes. The document aims to educate on PPE for medical professionals during the COVID-19 pandemic.
Face mask and respirators are the major device which comes under both protective clothing and medical textiles. The design and development of such protective clothing is driven by the choice of materials, as defined by the social, psychological or physiological requirement of user, choice of technologies as defined by desired functionality and ergonomic considerations, assembly methods, sizing and fit. This paper specifically reviews the facemask and respirators with respect to right selection of mask functional, design and ergonomic requirements product development and its characteristics evaluation and test methods and few ongoing researches on filtration of nano sized particle. A. Muralikrishnan "Design and Development of Face Masks" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-6 | Issue-6 , October 2022, URL: https://www.ijtsrd.com/papers/ijtsrd51897.pdf Paper URL: https://www.ijtsrd.com/engineering/textile-engineering/51897/design-and-development-of-face-masks/a-muralikrishnan
Innomantra- Patent insights -Anti-Viral / Bacterial Face Mask -In the wake of...Innomantra
This Quick Patent Insights report is intended to bring industry a glimpse on the Anti-Viral Type of Face Masks. This is a sample study to help the society during Coronavirus(COVID19) pandemic out break. The patent insights portrayed can be used by industry experts, manufacturer’s, academicians, new market entrants, NGOs and individuals who are exploring to reinvent or invent and to solve the issue of shortage of anti-viral masks. We strongly believe that these insights to a great extent can help communities to build by Do-it-yourself by further downloading the relevant patent for further experimentation, incorporating several elements wherever possible.
The insight document covers Patent Applications/Grants varying from across the globe. Few of the highly cited references are active, while few others are only published/ expired or abandoned for reasons thereof. Needless, to say later ones are in the public domain already meaning the public is free to use it for their own good without invoking any infringement suite. However, several organizations and government could urge the owners to release their patent to the public domain given into the pandemic crisis. Well, this would be an ongoing debate for the next several weeks.
For the moment, we at Innomantra feel that the insights given as a part of the report can be used as a first step towards combating the current global crisis.
For any further/specific information please feel free to reach us on contact@innomantra.com
The document is a summer internship project report on sales and marketing for AFPROTECH products, which produces a Wet Umbrella Wrapper Machine. The intern was tasked with increasing sales and marketing by targeting new industries like temples and colleges. Some key findings included that hotels and hospitals were interested due to cleanliness needs, while corporate offices found the recurring costs expensive. The intern proposed solutions like a pay-per-use model for temples to increase sales without upfront costs. The internship helped identify new potential markets and strategies to expand sales of the Wet Umbrella Wrapper Machine.
The document discusses routine maintenance checks that should be performed on a vehicle weekly. It describes how to check fluid levels such as engine oil, transmission fluid, brake fluid, coolant, power steering fluid, windshield washer fluid, and battery acid level. Basic safety checks are also outlined like inspecting lights, glass, seat belts, tires, and for leaks. The proper locations and procedures for performing each check are explained. A diagram labels parts of the car related to routine maintenance. Performing these minor weekly checks can help reduce breakdowns and save money on repairs.
The document discusses personal protective equipment (PPE), describing PPE as clothing or equipment that protects the body from workplace hazards. It outlines the different types of PPE including foot, eye, face, hearing, head, hand, respiratory, and body protection. The document stresses that PPE should only be used after engineering and administrative controls and that its effectiveness relies on proper selection, use, maintenance and monitoring.
This study evaluated the filtration efficiency of double strap tie-on surgical masks using monodispersed polystyrene latex beads of 0.5 um, 1.0 um, and 2.0 um as challenge aerosols. The masks were tested on a manikin head both with and without sealing the edges to measure penetration through the filtering material and potential leakage. Particle concentrations upstream and downstream of the mask were measured and efficiency was calculated. For unsealed masks, efficiency ranged from 3-43% for 0.5 um particles, 58-75% for 1.0 um particles, and 58-79% for 2.0 um particles. For sealed masks, efficiency was higher at 42-51% for 0
Not all face Masks are the same . This blog explains the difference between cloth masks, medical masks and FFP2, filtering respirators and which is the correct way to understand certifications and filtration efficiency
Microneedles in Transdermal Drug Delivery SystemChandni Verma
This presentation includes the recent fivE year patentS as well as research articles mainly on dissolving needles and further description on typesof mns,mechanism of drug release,etc
How to Manufacture Disposable Surgical Devices, Medical Products, Hospital Pr...Ajjay Kumar Gupta
Medical and surgical device manufacturers worldwide produce a multitude of items that are intended for one use only. The primary reason is infection control; when an item is used only once it cannot transmit infectious agents to subsequent patients. Like medicines and other health technologies, they are essential for patient care – at the bedside, at the rural health clinic or at the large, specialized hospital. The demand of these goods is not only because of their “one time use” property but also due to the hygienic methods adopted to produce them. From manufacturing to Marking, production of disposable goods is stacked with numerous standards and regulations.
See more
http://goo.gl/3LI9Za
http://goo.gl/IH6fTG
http://www.entrepreneurindia.co/
Blood bag manufacturing process, Blood bag production plant, Blood bag production plant, book on Medical and Surgical Disposable Products, Business Plan for a Startup Business, Business start-up, Catheter Production Equipments, cotton and surgical bandages manufacturing, Disposable Glove Making Machine, Disposable medical syringe & needle production plant, Disposable Plastic Gloves, Disposable Plastic Syringe: Manufacturing Business Idea, Disposable Plastic Syringes Manufacturing Plant, Disposable Surgical Gowns Products, disposable surgical wear manufacturing, Disposable syringe - Small Industry, Disposable syringe making machine, Disposable syringe manufacturing plant, Disposable syringe manufacturing process, Disposable Syringe Plant, Glove manufacturing process, Glove production line, Great Opportunity for Startup, Healthcare Disposable Surgical Instruments, Hospital Surgical Items List, How catheter is made - material, history, used, structure, procedure, how catheters are made, How to Manufacture Blood Bags, How to Manufacture Flexible PVC Blood Bags, How to manufacture Medical and Surgical Disposable products, How to manufacture Medical Disposable products, How to manufacture Surgical Disposable products, How to Start a Medical and Surgical Disposable Production Business, How to Start Medical and Surgical Disposable production Industry in India, Injection needle manufacturing process, Intravenous Cannula production, Medical Disposables and Surgical Disposables, Medical Glove Plant, Medical Products, Hospital Products, Surgical Products manufacturing, Medical Products: Surgical Blades, Urine Bags, Catheters, Most Profitable Surgical Disposable products manufacturing Business Ideas, New small scale ideas in Surgical Disposable products manufacturing industry, Non-woven Glove Making Machine, Packaging for Medical Devices, Plants for the Production of Disposable Medical Devices, Process technology books, Surgical Bandage Making: Small Business Project, surgical bandage manufacturing process, surgical cotton bandage production, surgical cotton manufacturing process, surgical disposable products manufacturing
The European standard EN 14683 describes requirements and testing methods for medical face masks. It includes design, production, performance requirements and tests for surgical masks to limit transmission of infectious substances from medical staff to patients. The standard establishes two types of medical masks - Type I for general public use and Type II/IIR for medical professionals, with different bacterial filtration and splash resistance requirements. Key tests evaluate bacterial filtration efficiency, air permeability, cleaning, and compliance with biocompatibility standards.
DESIGN AND FABRICATION OF PAPR SYSTEM FOR POWDER COATINGvivatechijri
The project defines the problem faced by the workers in powder coating industries. Powder coating is
a process by which electrostatically charged powder is applied on to an earthed object. The health effects that a
worker may experience following exposure to a hazardous chemical can become apparent after a short period of
time, and includes headaches, nausea or vomiting, dizziness, burns to skin and eyes an irritation to the nose,
throat and lungs. Long term health effects include asthma, dermatitis, kidney or liver damage, cancer and central
nervous system. The solution for the factors affecting the worker’s health and life, should provide the proper
protective equipment. Our design approach provides proper ventilated respiratory system to the person wearing
personal protective equipment, with air purification by providing the filters which will purify the air pumped
inside the kit.
The document discusses different types of face masks and respirators, including their purposes, designs, and appropriate usage. Surgical masks create a barrier to prevent transmission of infectious agents and are meant to block large particles. N95 respirators can filter 95% of airborne particles and are designed to achieve a close facial fit to protect the wearer. Factors like activities, medical conditions, and communication needs may impact mask feasibility for some individuals. Proper usage and limitations are outlined for surgical masks and N95 respirators.
In order to satisfy man's fundamental necessities, textile items are crucial. We frequently just think about textiles as the clothing we wear. Obviously, the majority of textiles are manufactured and consumed in the apparel business. However, textiles have a significant role in every area of our life, from conception to death. The history of textile use spans more than 8500 years. Textile technology advancements are not generally recognised in other industries as they are in the apparel sector. The crucial roles that textiles play in various sectors are described in the following presentation.
This document discusses rational use of personal protective equipment (PPE) during the COVID-19 era. It outlines the components of PPE including masks, gloves, gowns and describes their proper use. Face masks and respirators are discussed in detail, including the differences between medical masks and N95 respirators. Guidelines are provided for donning and doffing PPE correctly as well as extended use and limited reuse of equipment to address shortages. Proper sanitization of phones and other frequently touched items is also recommended.
Guidance on gloves maintenance in Isolator and RABSPalash Das
A faulty glove or sleeve assembly represents a route of contamination and a critical breach of Isolator integrity. Within this article we will discuss about all these aspects.
This document provides guidelines for selecting fabrics and designing fabric face masks for general public use in South Africa during the COVID-19 pandemic. It recommends that masks have at least two breathable fabric layers to act as a barrier against droplets while being comfortable enough to wear. The inner layer should be soft against the face, while the middle layer (optional) can be a non-woven fabric for filtering, and the outer layer faces outward. Proper fit and instructions for use and cleaning are also important. Local textile manufacturers are listed to support South Africa's industrial policy objectives.
Manufacturing of Medical Disposable Face Masks. Startup Business Opportunities in Disposable Surgical Mask.
A surgical mask, additionally known as a procedure mask, medical mask or simply as a face mask, is meant to be worn by health professionals during surgery and through nursing to catch the bacteria shed in liquid droplets and aerosols from the wearer's mouth and nose. They not designed to protect the wearer from inhaling airborne bacteria or virus particles and are less effective than respirators, like N95 or FFP masks, which give higher protection because of their material, form and tight seal.
For More Details, Click Here: - https://niir.org/profile-project-reports/profiles/hygiene-products-essential-personal-hygiene-products-feminine-hygiene-products/z,,6c,0,a/index.html
Contact us
Niir Project Consultancy Services
An ISO 9001:2015 Company
106-E, Kamla Nagar, Opp. Spark Mall,
New Delhi-110007, India.
Email: npcs.ei@gmail.com , info@entrepreneurindia.co
Tel: +91-11-23843955, 23845654, 23845886, 8800733955
Mobile: +91-9811043595
Website: www.entrepreneurindia.co , www.niir.org
This case report describes the use of a silicone implant for augmentation rhinoplasty in a 17.5-year-old male patient with a saddle nose deformity caused by a previous nasal infection. A silicone implant was placed through an incision in the columella to reconstruct the nasal dorsum. The postoperative result showed good correction of the nasal deformity with no complications. The report discusses the advantages of silicone implants for augmentation rhinoplasty, including affordability, low risk of extrusion or infection when placed properly, and the ability to provide mild to moderate height increases with good cosmetic outcomes.
Filtration technology is widely used but additive manufacturing has not yet been applied to filter production. The document proposes developing additive technologies for printing filters from metals and ceramics with controlled porosity. This would allow for more complex filter designs not possible with traditional methods. The plan involves developing specialized 3D printers then working with industrial partners to produce and test large filters.
Additive manufacturing is currently at a rapid growth stage. New processes and technologies are being created, the old ones are being optimized.
There are already many companies in the market that produce various 3D printers, develop software and print parts.
Some perceive additive technologies as technologies to create new types of machine-tools, others as independent technologies.
But the commercial success of additive technologies has already caused discussion of different approaches. We're talking about the type of architecture. It's a closed and open architecture of devices for additive technologies.
Does it make sense to use open architecture in this sphere of technology?
Fine Systems Technologies provides technology consulting services such as product and technology development, requirements analysis, design, and project support. They work with clients to develop new devices, technologies, and production processes. Their team of engineers, designers, and technology specialists can complement a client's internal development department or handle full product development. Services are tailored to each project and may include consultation, concept development, prototyping, small production runs, and integration of electronics, optics, and other components.
Компания «Тонкие системные технологии» проводит техническое и технологическое консультирование.
Если нужно создать устройство, технологию, установку – мы можем в этом помочь.
Если нет собственного отдела разработок – мы можем разработать для вас продукт или технологию.
Компания «Тонкие системные технологии» создана для работы с нестандартными проектами. В ситуации, когда нет типовых решений, при разработке технологии или устройства необходим специальный подход к работе с поставленными задачами.
Это работа над новыми продуктами и технологиями, новые рынки и бизнес-модели, проекты на стыке нескольких областей, переход от идеи к разработке и от разработки к производству.
Компания «Тонкие системные технологии» сформирована для работы с новыми нестандартными проектами. Это необходимо при разработке новых технологий и продуктов.
In XWS sources light is produced by plasma
which emits light due to the continuous
energy input from a laser (optical discharge).
These light sources have been
developed as a replacement of traditional
gas discharge lamps (Deuterium-,
Tungsten-, Xenon- lamps etc.) and LEDs.
Compared to these, XWS sources have a
wider spectral range and higher spectral
brightness. Moreover, the technology of
plasma light sources allows developing
units with specific characteristics which
match special customer applications.
XWS — плазменный широкополосный источник излучения с лазерной накачкойVladislav Troshin
XWS — плазменный широкополосный источник излучения с лазерной накачкой.
В источниках XWS излучение даёт плазма, светящаяся под действием непрерывного лазерного излучения (оптический разряд). Эти источники разработаны для замены традиционных газоразрядных ламп (ксеноновых, дейтериевых, ртутных) и светодиодов. По сравнению с ними XWS имеет более высокую яркость и расширенный спектральный диапазон. Кроме того, технология плазменных источников излучения позволяет разрабатывать устройства со специфическими характеристиками для решения особых задач пользователей.
The document describes the structure of DNA and RNA molecules at the nucleotide level. It shows the phosphate backbone and sugar-phosphate groups that make up the structure, with nitrogenous bases bonding between strands in the DNA double helix or within RNA. Various DNA and RNA sequences are displayed.
“An Outlook of the Ongoing and Future Relationship between Blockchain Technologies and Process-aware Information Systems.” Invited talk at the joint workshop on Blockchain for Information Systems (BC4IS) and Blockchain for Trusted Data Sharing (B4TDS), co-located with with the 36th International Conference on Advanced Information Systems Engineering (CAiSE), 3 June 2024, Limassol, Cyprus.
UiPath Test Automation using UiPath Test Suite series, part 5DianaGray10
Welcome to UiPath Test Automation using UiPath Test Suite series part 5. In this session, we will cover CI/CD with devops.
Topics covered:
CI/CD with in UiPath
End-to-end overview of CI/CD pipeline with Azure devops
Speaker:
Lyndsey Byblow, Test Suite Sales Engineer @ UiPath, Inc.
In his public lecture, Christian Timmerer provides insights into the fascinating history of video streaming, starting from its humble beginnings before YouTube to the groundbreaking technologies that now dominate platforms like Netflix and ORF ON. Timmerer also presents provocative contributions of his own that have significantly influenced the industry. He concludes by looking at future challenges and invites the audience to join in a discussion.
Cosa hanno in comune un mattoncino Lego e la backdoor XZ?Speck&Tech
ABSTRACT: A prima vista, un mattoncino Lego e la backdoor XZ potrebbero avere in comune il fatto di essere entrambi blocchi di costruzione, o dipendenze di progetti creativi e software. La realtà è che un mattoncino Lego e il caso della backdoor XZ hanno molto di più di tutto ciò in comune.
Partecipate alla presentazione per immergervi in una storia di interoperabilità, standard e formati aperti, per poi discutere del ruolo importante che i contributori hanno in una comunità open source sostenibile.
BIO: Sostenitrice del software libero e dei formati standard e aperti. È stata un membro attivo dei progetti Fedora e openSUSE e ha co-fondato l'Associazione LibreItalia dove è stata coinvolta in diversi eventi, migrazioni e formazione relativi a LibreOffice. In precedenza ha lavorato a migrazioni e corsi di formazione su LibreOffice per diverse amministrazioni pubbliche e privati. Da gennaio 2020 lavora in SUSE come Software Release Engineer per Uyuni e SUSE Manager e quando non segue la sua passione per i computer e per Geeko coltiva la sua curiosità per l'astronomia (da cui deriva il suo nickname deneb_alpha).
Unlock the Future of Search with MongoDB Atlas_ Vector Search Unleashed.pdfMalak Abu Hammad
Discover how MongoDB Atlas and vector search technology can revolutionize your application's search capabilities. This comprehensive presentation covers:
* What is Vector Search?
* Importance and benefits of vector search
* Practical use cases across various industries
* Step-by-step implementation guide
* Live demos with code snippets
* Enhancing LLM capabilities with vector search
* Best practices and optimization strategies
Perfect for developers, AI enthusiasts, and tech leaders. Learn how to leverage MongoDB Atlas to deliver highly relevant, context-aware search results, transforming your data retrieval process. Stay ahead in tech innovation and maximize the potential of your applications.
#MongoDB #VectorSearch #AI #SemanticSearch #TechInnovation #DataScience #LLM #MachineLearning #SearchTechnology
Communications Mining Series - Zero to Hero - Session 1DianaGray10
This session provides introduction to UiPath Communication Mining, importance and platform overview. You will acquire a good understand of the phases in Communication Mining as we go over the platform with you. Topics covered:
• Communication Mining Overview
• Why is it important?
• How can it help today’s business and the benefits
• Phases in Communication Mining
• Demo on Platform overview
• Q/A
Essentials of Automations: The Art of Triggers and Actions in FMESafe Software
In this second installment of our Essentials of Automations webinar series, we’ll explore the landscape of triggers and actions, guiding you through the nuances of authoring and adapting workspaces for seamless automations. Gain an understanding of the full spectrum of triggers and actions available in FME, empowering you to enhance your workspaces for efficient automation.
We’ll kick things off by showcasing the most commonly used event-based triggers, introducing you to various automation workflows like manual triggers, schedules, directory watchers, and more. Plus, see how these elements play out in real scenarios.
Whether you’re tweaking your current setup or building from the ground up, this session will arm you with the tools and insights needed to transform your FME usage into a powerhouse of productivity. Join us to discover effective strategies that simplify complex processes, enhancing your productivity and transforming your data management practices with FME. Let’s turn complexity into clarity and make your workspaces work wonders!
Maruthi Prithivirajan, Head of ASEAN & IN Solution Architecture, Neo4j
Get an inside look at the latest Neo4j innovations that enable relationship-driven intelligence at scale. Learn more about the newest cloud integrations and product enhancements that make Neo4j an essential choice for developers building apps with interconnected data and generative AI.
Why You Should Replace Windows 11 with Nitrux Linux 3.5.0 for enhanced perfor...SOFTTECHHUB
The choice of an operating system plays a pivotal role in shaping our computing experience. For decades, Microsoft's Windows has dominated the market, offering a familiar and widely adopted platform for personal and professional use. However, as technological advancements continue to push the boundaries of innovation, alternative operating systems have emerged, challenging the status quo and offering users a fresh perspective on computing.
One such alternative that has garnered significant attention and acclaim is Nitrux Linux 3.5.0, a sleek, powerful, and user-friendly Linux distribution that promises to redefine the way we interact with our devices. With its focus on performance, security, and customization, Nitrux Linux presents a compelling case for those seeking to break free from the constraints of proprietary software and embrace the freedom and flexibility of open-source computing.
Building Production Ready Search Pipelines with Spark and MilvusZilliz
Spark is the widely used ETL tool for processing, indexing and ingesting data to serving stack for search. Milvus is the production-ready open-source vector database. In this talk we will show how to use Spark to process unstructured data to extract vector representations, and push the vectors to Milvus vector database for search serving.
UiPath Test Automation using UiPath Test Suite series, part 6DianaGray10
Welcome to UiPath Test Automation using UiPath Test Suite series part 6. In this session, we will cover Test Automation with generative AI and Open AI.
UiPath Test Automation with generative AI and Open AI webinar offers an in-depth exploration of leveraging cutting-edge technologies for test automation within the UiPath platform. Attendees will delve into the integration of generative AI, a test automation solution, with Open AI advanced natural language processing capabilities.
Throughout the session, participants will discover how this synergy empowers testers to automate repetitive tasks, enhance testing accuracy, and expedite the software testing life cycle. Topics covered include the seamless integration process, practical use cases, and the benefits of harnessing AI-driven automation for UiPath testing initiatives. By attending this webinar, testers, and automation professionals can gain valuable insights into harnessing the power of AI to optimize their test automation workflows within the UiPath ecosystem, ultimately driving efficiency and quality in software development processes.
What will you get from this session?
1. Insights into integrating generative AI.
2. Understanding how this integration enhances test automation within the UiPath platform
3. Practical demonstrations
4. Exploration of real-world use cases illustrating the benefits of AI-driven test automation for UiPath
Topics covered:
What is generative AI
Test Automation with generative AI and Open AI.
UiPath integration with generative AI
Speaker:
Deepak Rai, Automation Practice Lead, Boundaryless Group and UiPath MVP
AI 101: An Introduction to the Basics and Impact of Artificial IntelligenceIndexBug
Imagine a world where machines not only perform tasks but also learn, adapt, and make decisions. This is the promise of Artificial Intelligence (AI), a technology that's not just enhancing our lives but revolutionizing entire industries.
Observability Concepts EVERY Developer Should Know -- DeveloperWeek Europe.pdfPaige Cruz
Monitoring and observability aren’t traditionally found in software curriculums and many of us cobble this knowledge together from whatever vendor or ecosystem we were first introduced to and whatever is a part of your current company’s observability stack.
While the dev and ops silo continues to crumble….many organizations still relegate monitoring & observability as the purview of ops, infra and SRE teams. This is a mistake - achieving a highly observable system requires collaboration up and down the stack.
I, a former op, would like to extend an invitation to all application developers to join the observability party will share these foundational concepts to build on:
Threats to mobile devices are more prevalent and increasing in scope and complexity. Users of mobile devices desire to take full advantage of the features
available on those devices, but many of the features provide convenience and capability but sacrifice security. This best practices guide outlines steps the users can take to better protect personal devices and information.
Goodbye Windows 11: Make Way for Nitrux Linux 3.5.0!SOFTTECHHUB
As the digital landscape continually evolves, operating systems play a critical role in shaping user experiences and productivity. The launch of Nitrux Linux 3.5.0 marks a significant milestone, offering a robust alternative to traditional systems such as Windows 11. This article delves into the essence of Nitrux Linux 3.5.0, exploring its unique features, advantages, and how it stands as a compelling choice for both casual users and tech enthusiasts.
2. 2
Types of masks
In terms of certification and technology, masks are divided
into the following groups
Face masks
They're not medical. Minimum requirements for functionality. It can be made
industrially, on small manufactures, hand-made. Efficiency may vary, but by
default, they are considered to be without protective functions in case of
serious threats. Not recommended for use in medicine.
Non-medical face masks, masks, common mask, etc.
Different materials and technologies.
A medical face mask (surgical mask or procedure mask)
Medical masks are used to prevent breathing transmission of particles and
droplets, including various infectious agents.
They should cover the nose, mouth, and chin. Must be certified. Have different
levels of protection. Affected by different standards.
Only produced under industrial conditions.
Covered by standard EN 14683:2014.
Respirators, half face masks
Apply to personal protective equipment (PPE). Should be able to trap both
solid particles and liquid droplets, in some cases gaseous substances. May
have additional elements such as filters, valves, etc.
It is important to note that in many cases there is no filtration when
exhaled.
Respirators, half face masks, filtering face piece (FFP).
Subject to EN 149:2001+A1:2009.
5. 5
Medical face mask
There are several classifications of medical masks
The masks are tested on the following parameters:
- Test Method for Evaluating the Bacterial Filtration Efficiency (BFE) of
Medical Face Mask Materials, Using a Biological Aerosol of Staphylococcus
aureus;
- Test method for determining the initial efficiency of materials used in
medical face masks to penetration by particulates using latex spheres;
- Test method for resistance of medical face masks to penetration by synthetic
blood (horizontal projection of fixed volume at a known velocity);
- Test method for resistance of materials used in protective clothing to
penetration by blood-borne pathogens using Phi-X174 bacteriophage
penetration as a test system
Additionally, the safety of the used materials, flammability, etc. is tested.
Classifications by:
- EN 14683:2014. Medical face masks — Requirements and test
Methods;
- ASTM (American Society of Testing and Materials American Society of Testing
and Materials (ASTM);
- Numerous local standards
https://www.beckershospitalreview.com/quality/the-4-fs-of-medical-mask-selection.html
https://www.primed.ca/clinical-resources/astm-mask-protection-standards/
https://healthcentricadvisors.org/wp-content/uploads/2017/04/3_MaskEnomics_Poster_2012.pdf
https://www.astm.org/standardization-news/?q=features/standards-medical-face-masks-and-protective-
clothing-.html
8. 8
MEDICAL FACE MASK TESTS AND REQUIREMENTS
https://www.nelsonlabs.com/wp-content/uploads/2020/03/Face-Mask-Testing-Requirements.pdf
9. 9
Multilayer construction
Modern medical masks have a multi-layered design. 3-layer masks are
found and manufactured, but there are masks from 4-5(7) layers
Layer Description and properties Materials Importance
Outer layer
/
Cover layer
The outer layer is designed for rough
filtering of large particles. Hydrophobic
properties for rejecting liquids are required.
Usually colored.
Non-woven fabric: PP Spunbond
(SBPP). Non-woven fabric:
Melt-blown polypropylene.
PP + PE. PET. Rayon.
Need
Additional
layer /
Support
layer
An additional layer. It can provide additional
filtration, contain additional compounds to
catch odors and liquids, oils, etc. It can be
located outside for exterior applications.
All listed filtering
materials. In addition,
various impregnations,
activated carbon, graphene and
other materials can be used.
Optional or
marketing
Basic
Filter
Layer
Basic filter layer. The finest filtration.
Designed for basic filtration. Electrostatic
properties are mandatory.
Non-woven fabric: Melt-blown
polypropylene.
Micro spun fibers
polypropylene + melt-blown
polypropylene. PTFE.
Need. Can
be
duplicated.
Additional
/ Support
layer
An additional layer. It can provide additional
filtration, contain additional compounds to
catch odors and liquids, oils, etc.
All listed filtering
materials. In addition,
various impregnations,
activated carbon, graphene and
other materials can be used.
Optional or
marketing
Internal
layer /
Shell layer
The inner layer is designed to filter exhaled
and breathable air. It provides contact with
the face. Hydrophilic properties for the
absorption of liquids are required. Must be
soft so as not to injure the skin.
Non-woven fabric: PP Spunbond.
PP + PE. PET. Rayon. Cotton.
Thermal Bonded Polypropylene.
Need
10. 10
Multilayer construction
In addition to the basic layers, there are
other parts of the masks
The main parts:
- Nose Wire (100% PE, alluminium);
- Elastic Band (spandex and polyester)
No threads are used in modern masks. The layers are
joined mainly by ultrasonic welding. In rare cases, an
adhesive joint is used.
Also, different models use different strips and foams
for liquid trapping (anti-fog), foam seals for the
nose, etc.
There are masks with different shields to protect the
eyes, neck, etc.
http://www.95mask.com/news/disposable-surgical-face-mask-material-
details.html
11. 11
Multilayer construction
The basic concept of building medical masks
The design of medical masks is based on the concept of the multilayer.
The number of layers can vary. But the basis is three-ply (3-ply)
masks.
1. The outer layer has two functions. Rough pre-filtration and
protection against liquid droplets. Rough filtration is needed to
increase the operating time of the main filter layer. Hydrophobicity
is needed to protect against liquid droplets;
2. The main or middle layer. Basic filter layer. Serves as the main
filter against fine particles. The basis of the mechanism is
electrostatic filtration;
3. The inner layer - has three functions. Exhalation filtration and
additional filtration on inhalation, moisture absorption, facial
skin protection from abrasion.
All other outer or inner layers are used to obtain additional
properties of the mask.
https://www.georgetownpharmacy.com.my/pages/surgical-masks-which-side-out
12. 12
Basic parameters for the design of masks
There is a large number of medical masks of different designs
and constructions on the market. The basic standards specify
only the functional parameters that medical masks must
satisfy. This slide covers the "designer" for medical masks
The class of masks can be changed by the following parameters:
- Changing the number of layers. Adding layers with different
characteristics can improve the performance of masks. However,
increasing the number of layers will make it difficult to breathe
and may not exceed a specific limit.
- Changing the characteristics of individual layers. Nonwovens have
properties such as thickness, density, porosity, and fibers
thickness. By changing these properties, individual characteristics
can be improved. But then again, if the thickness is too thick, it
will make breathing difficult;
- A change in the structure of the layers. That is, creating composite
layers from different types of materials;
- Modification of the layers by physical and physical-chemical
methods;
- Additional additives to the layers to give different properties;
- Use of new materials
In addition, the design of the masks may also be suitable to go beyond
the current standards. For example, the design of masks with breathing
disabilities for short periods of time. For example, shop visits, short
trips on public transport. This can be the case for masks with a small
number of layers and less demanding materials.
15. 15
Mechanical filter respirator
Respirators, respirator masks, half-face masks, mechanical
filter respirator, FFP (filtering facepiece) mask. There are
several classifications of such respirators
Classifications by:
- United States NIOSH-42CFR84;
- Europe EN 149:2001+A1:2009
- China GB2626-2006;
- Australia/New Zealand AS/NZA 1716:2012;
- Korea 1st class (Korea KMOEL - 2017-64);
- DS (Japan JMHLW-Notification 214, 2018)
https://www.cdc.gov/niosh/npptl/topics/respirators/pt84abs2.html
Europe EN 149:2001+A1:2009: Respiratory protective devices
Filtering half masks to protect against particles. Requirements,
testing, marking.
FFP3, FFP2/N95 and analog respirators are used for work in biologically
hazardous environments.
They are not designed to protect against allergens (FFP3) for several
reasons. In the case of pollen, it is meaninglessly expensive, although
it will work. In the case of chemical compounds, it won't work without
additional adsorbing layers.
16. 16
Mechanical filter respirator
Example of a comparison
of respirators meeting
similar standards
https://multimedia.3m.com/m
ws/media/1791500O/comparis
on-ffp2-kn95-n95-filtering-
facepiece-respirator-classes-
tb.pdf
18. 18
Mechanical filter respirator
Mask respirators are designed for long-term work in
contaminated environments. This imposes many restrictions on
their construction, design, and testing
The following features of respirator masks can be noted:
- The edges of the respirator must fit tightly to the face;
- Must have a "volume design" for a small amount of air between the
mouth, noses, and respirator;
- Must be tested for breathing quality;
- Must be tested under working conditions;
- Must be designed to absorb moisture;
- Preferably reduced overheating of the face during prolonged work
In general, they are designed to filter the air from solids and liquid
droplets.
https://multimedia.3m.com/mws/media/601738O/3m-disposable-respirators-
brochure.pdf?&fn=MFR%2520Product%2520Catalogue.pdf
https://multimedia.3m.com/mws/media/1829292O/3m-aura-particulate-respirator-9300-
series-technical-datasheet.pdf
https://www.cdc.gov/niosh/npptl/topics/respirators/factsheets/respsars.html
19. 19
Mechanical filter respirator
There are several designs of respirators
- Fold-flat respirators - folding respirators, folded to
reduce volume. It can be folded horizontally or
vertically.
- Cone, cup or common respirators - have a rigid
construction. It is not recommended to fold or wrinkle;
- Valveless respirators - inhalation and exhalation pass
through the respirator material and the air is cleaned
both on inhalation and exhalation;
- Respirators with a valve - an additional valve are used
for exhalation. Usually, the air passing through it is
not filtered. There may be several valves on the sides
of the respirator or one in the center
Reusable masks, similar to respirators, with changeable
filters and valves, are not classified as respirators.
Such products are intended for individual use only.
The valve is set with two targets:
- to improve the exhalation;
- heat removal
20. 20
Multilayer construction
Modern respirators have at least 4 layers in their design
Layer Description and properties Materials Importance
Outer
layer /
Cover
layer
The outer layer is designed for
rough filtering of large
particles. Hydrophobic
properties for rejecting
liquids are required.
Non-woven fabric: PP.
Non-woven fabric: Melt-
blown polypropylene.
Spunbond (SBPP).
PP + PE. PET. Rayon.
Need
Basic
Filter
Layer
Basic filter layer. The finest
filtration. Designed for basic
filtration. Electrostatic
properties are mandatory.
Non-woven fabric: Melt-
blown polypropylene.
Micro spun fibers
polypropylene + melt-
blown polypropylene.
PTFE.
Need
Hydrophi
lic
layer /
Frame
support
layer
This layer is designed to
collect moisture from
breathing, to maintain the
shape of the respirator and to
provide additional filtration.
Non-woven fabric: PP
Spunbond.
PP + PE. PET. Rayon.
Cotton (PP or cotton).
Thermal Bonded
Polypropylene.
Modacrylic.
Need
Internal
layer /
Shell
layer
The inner layer is designed to
filter exhaled and breathable
air. It provides contact with
the face. Hydrophilic
properties for the absorption
of liquids are required. Must
be soft so as not to injure the
skin. Forming a frame.
Non-woven fabric: PP
Spunbond.
PP + PE. PET. Rayon.
Cotton (PP or cotton).
Thermal Bonded
Polypropylene.
Need
21. 21
Multilayer construction
General description of the functioning of the
respirator
When you inhale:
- The air passes through the first filter layer. Large
particles are rejected or filtered and liquid
droplets are trapped;
- The air passes through a fine filter layer. This is
usually an electrostatic filter that traps the
particles. Since the fine particles almost always
have a charge on the surface, they stick to the
filter fibers;
- The air passes through a fourth layer. Here,
additional filtration occurs;
- The air passes through the last layer where
additional filtration is provided.
On exhalation:
- The air passes through the fourth layer, providing
basic rough filtration;
- Air passes through the third layer. It also traps the
liquid that emerges from breathing, accumulates
saliva, perspiration, etc.;
- The air passes through the second layer. Fine
filtration takes place here;
- The air passes through the last layer where
additional filtration is provided.
22. 22
Multilayer construction
Long operating time and moisture collection and
removal
Respirators are designed for continuous operation (up
to 6 hours). During this time, a large amount of
moisture accumulates when breathing, saliva, sweat.
The third layer is used to accumulate this moisture.
Which should accumulate moisture.
In the case of respirators with a valve, it is assumed
that some moisture can be removed without filtration.
However, such respirators are not recommended for
medicine.
Interaction with the skin.
The softest anti-abrasion materials are selected for
the layer that comes into contact with the face when
the respirator is worn for a long time. They only
provide coarse filtration.
Ideally, they should drain moisture into the layer to
accumulate it.
23. 23
Multilayer construction
Additional layers
In addition to the 4 basic layers in modern respirators
can be up to 10 layers. Usually 5-7 layers in most
models.
The additional layers may provide the following
functions:
- Additional rough filtration;
- Additional fine filtration;
- Oils hold;
- Odor catching, such as the addition of activated
carbon and graphene;
- Additional shape support layers
Basic limits on the number of layers:
- The breathing ability of the respirator must be
maintained. Too many layers will make it difficult to
breathe;
- It is necessary to maintain heat removal, increased
sweating will lead to premature filling of the
collecting fluid layer and loss of filtering
functions by the respirator.
24. 24
Multilayer construction
Other parts of the respirator
The main parts:
- Nose Wire (aluminum or100% PE). Required for fixation
on the face and nose. When using a respirator, bend
hands to the shape of the nose;
- Elastic Band or strap (spandex and polyester,
polyisoprene);
- Staples (steel or aluminium);
- Nose foam (polyurethane). Used to reduce nose
abrasion.
To fit tightly to the face, the edge of the respirator
must be flat.
No threads are used in modern respirators. The layers
are joined mainly by ultrasonic welding. In rare cases,
an adhesive joint is used.
Also, different models use different strips and foams
for liquid trapping (anti-fog), foam seals for the
nose, etc.
There are masks with different shields to protect the
eyes, neck, etc.
25. 25
Multilayer construction
Other parts of the respirator
Some models use an additional exhalation valve.
Usually, it does not filter out the exhaled air. It is
designed to remove heat and liquid.
Valve materials:
- Valve (polyproylene);
- Valve diaphragm (polyisoprene)
26. 26
Multilayer construction
The basic concept of building respirators
The design of respirators is based on the concept of the multilayer.
The number of layers can vary. There are at least four basic layers in
modern respirators.
1. The outer layer should provide rough filtration, push away liquid
droplets, i.e. have hydrophobic properties. Particle holding is
necessary to extend the life of the fine filter;
2. The fine filter is used to trap fine particles. It is due to
electrostatic filtration.
3. The layer of moisture accumulation. It is used to remove moisture
that occurs during breathing, saliva, sweat. Also, this layer
supports the shape of the respirator;
4. A layer to prevent abrasion of the face. It provides rough
filtration;
5. The respirator should fit tightly to the face. The edges of the
respirator should be flat.
All other outer or inner layers are used to obtain additional
properties of the respirators.
27. 27
Basic parameters for the design of respirators
There are a few major respirator manufacturers on the
market. They produce many different models. This slide
covers the "designer" for respirators
The design of the respirators is not directly mentioned in
existing standards. Respirators are tested for performance only.
The following principles can be proposed for the design of
respirators:
- Change in the number of layers. Adding new layers. Changing the
functions of the layers, etc.;
- Changing the characteristics of individual layers. It can be
the use of different materials, change the density of layers,
thickness, porosity, etc.;
- Changing the shape of the respirator. There are hard-fitting
and folding respirators on the market;
- Introduction of additional materials into the layers of the
respirators;
- Changing the design of individual layers. For example, using
layers of the same material or using composite layers. For
example, SS, SMS, SM and similar;
- Shortening the working time of the respirators for use in
niches where several hours of work are not necessary.
In any case, the respirators are designed. There are no uniform
designs beyond the basic principles.
30. 30
Masks and respirators hybrid
Due to the epidemic of the new virus, medical
professionals are now in many cases required to use
N95(99) or FFP2(3) respirators
Medical masks do not provide the necessary protection when
dealing with virus diseases. They don't fit tightly to the face.
They do not provide the necessary filtering. For this reason,
medical professionals are now using respirators in routine
procedures that previously did not require this level of
protection.
But mass-use respirators are expensive, difficult to produce and
so on.
https://www.cdc.gov/coronavirus/2019-ncov/hcp/checklist-n95-strategy.html
https://www.businessinsider.com/types-of-masks-used-for-coronavirus-outbreak-n95-
surgical-2020-3
https://www.vox.com/2020/4/8/21209895/coronavirus-face-masks-n95-covid-19-ppe-
shortage
A possible solution to the problem may be an intermediate
solution. Special masks similar to respirators are available on
the market.
https://www.amazon.com/Medline-Surgical-Style-Non27381-Pound/dp/B00B973OYM
https://www.walgreens.com/store/c/walgreens-face-mask,-cone-
style/ID=prod6172910-product
https://products.halyardhealth.com/infection-prevention/facial-respiratory-
protection/masks-respirators/standard-cone-mask-with-headband-blue.html
31. 31
Masks and respirators hybrid
Designing masks to meet the standards for respirators
will require considerable effort. However, they may
conform to current standards for medical masks, but have
additional features that make them suitable for wider
use
It's necessary for the right match:
- Provide the necessary protection against drops and splashes;
- Provide a fitting to the face;
- Provide the right time to work;
- Provide a fixed form to preserve breathing air volume;
- Provide the necessary moisture-absorbing properties
This can be achieved in the following ways:
- Define specific performance characteristics for the medical
niche (reduce respirator running time);
- Using new materials (e.g. membrane waterproof materials);
- Use of additional constructions to maintain the shape
33. 33
Filters
Masks and respirators are by nature filters
There are several filtering mechanisms:
- Rough mechanical filtration. In this case, the filter pores are
smaller than the particles. The most effective method, but the
smaller the pore size, the harder it is to breathe through such
a filter. In the case of masks and respirators, it is used only
for large particles;
- Mechanical filtration. There are a few mechanisms. It is the
reflection, slowing down the particles by filter fibers.
Catching of particles by filter fibers (direct impact).
Grabbing the particles in the boundary layers of air near the
fibers (stopping their movement). Limiting the diffusion of the
particles by reducing the Brownian motion at the surface of the
fibers;
- Electrostatic filtration. If the fibers of the filter material
are charged, they attract or reject the charged particles.
Particles with positive charge are rejected by such filter,
particles with negative charge stick to the filter fibers. This
mechanism makes it possible to create filters to trap particles
smaller than the filter pores. Without this mechanism,
particles would pass through pores of similar material without
resistance. The basic material for such filters is molten blown
polypropylene
https://www.ncbi.nlm.nih.gov/pubmed/10957816
https://multimedia.3m.com/mws/media/99824O/spurious-research-on-electrostatic-
filter-performance-2001.pdf
https://journals.sagepub.com/doi/pdf/10.1177/155892501300800307
https://blogs.cdc.gov/niosh-science-blog/2009/10/14/n95/
35. 35
Commercial secrets
Production of respirators, masks, and other personal
protective equipment (PPE) is a big market. Manufacturers
are interested in keeping confidential detailed information
about the materials and technologies used
Manufacturers provide information about materials used from a chemical
point of view for safety assessment. Sometimes reference is made to
single-layer technology. But most of the technical information is
usually not mentioned.
This information includes:
- Characteristics of individual layers such as density, thickness,
porosity, etc..;
- Materials used for individual layers. For example, single-layer
fabrics (S or M), multi-layer fabrics (SS, SM, SMS, and others);
- Precise characteristics of each layer;
- General mask or respirator design
On the one hand, it complicates the development of new protection
equipment, by studying the advantages and disadvantages of separate
solutions, on the other hand, it allows us to create essentially new
designs.
36. 36
Commercial secrets
There are many ways to obtain information
Basic ways to find information:
- Searching by patents. The main intellectual property of companies is
collected in patents. Studying of patents will help to avoid
overlapping by patents. However, having a patent does not mean that
the information described there is used in reality;
For example, this link lists quite a lot of patents:
https://docs.google.com/spreadsheets/d/1SCCCKsGBNC8NmbsydtJfag3wwBl384Fc6hvFMntQfT
0/edit#gid=0
- Analysis of suppliers' offers. Since PPE manufacturers often purchase materials from third
parties, these materials are available for free sale;
http://www.ppnonwoven-fabric.com/sale-10683492-n95-30gsm-meltblown-nonwoven-fabric-
antibacterial-for-face-mask-purifier-filters.html
https://cihengnonwoven.en.made-in-china.com/product/TNyJfvWdZmhc/China-Custom-
Medical-Respirator-80GSM-N99-N95-Filter-Material-for-Making-Dust-Mask.html
https://www.alibaba.com/showroom/n95-fabric.html
- A direct study of the purchased samples. Including device analysis,
comparison with created samples
38. 38
Some parameters
For some types of fabrics, there are marks
It's possible to highlight:
S - spunbonded non-woven
M - meltblown non-woven fabric
S, SS, SMS, SMMS
http://www.ritschelastic.com/En_NewsInfo-77.html
Since nonwovens have a porosity that is difficult to determine
directly, the following two main parameters are used to evaluate their
functionality:
- GSM (Grams per Square Meter);
- Thickness;
- Diameter of elementary fibres;
- Porosity
Other important quality parameters:
- Tensile strength and elongation.
- Tear resistance;
- Bursting strength
https://www.technicaltextile.net/articles/influence-of-gsm-6502
Main parameters
39. Main parameters
39
Some parameters
Other required parameters may be listed as necessary:
- Filtering properties of layers;
- Hydrophobic properties of layers;
- Hydrophilic properties of layers;
- Ability to hold moisture;
- Applicability for skin contact (skin friendly);
- Construction properties of layers;
- Antibacterial protection
In addition, additives of various materials, such as activated carbon
and graphene, also provide additional properties. Those that can give
additional hydrophilic properties, trapping odors, etc.
Antibacterial properties of masks and respirators belong more likely to
marketing parameters. Since in the case of medical masks, the time of
use does not play a significant role in bacterial growth, in the case
of respirators, bacteria reproduce in any case in the water held by the
respirator.
In addition, the filtering properties of masks and respirators work
against bacteria. As the size of bacteria is always more than 0.2
microns. In other words, the filters must be able to catch the bacteria
in any case. The use of bactericidal materials for respiratory
protection is subject to safety tests and in most cases is questionable
either in terms of effectiveness or safety.
40. Basic properties of filter layers
40
Filtering properties of layers
Filtering properties are affected:
- Layer thickness;
The thicker the layer, the more likely it is to trap droplets or
particles. But too much individual layer thickness starts to interfere
with air flow, which makes breathing difficult.
- The density of the layer;
For filter media, the important parameter is the density of the layer.
The denser the layer, the better it filters, but the air flow decreases
similarly.
- Layer homogeneity;
In production it is possible to obtain fabrics with different densities
at different areas. This hurts the quality of the products in the
series.
- Distribution of pores by size;
An important parameter is the distribution of pores by size. If the
density and thickness of the layer are the same, if there are a large
number of large pores, the filtering properties will drop.
41. Spun bond filters
41
Filtering properties of layers
The basic characteristics of SP filters:
- Random arrangement of the fibers;
- Have a layered structure or cups;
- GSM 5-800, typical production 10-20;
- The diameter of the fibers is 1-50 microns, typical production is
15-35 microns;
- Good moisture holding due to large internal volume
Characteristics may vary from manufacturer to manufacturer. From
process features.
Melt blown filters
The basic characteristics of MB filters:
- Random arrangement of the fibers;
- Have a layered structure or cups;
- GSM 8-350, typical production 20-200;
- The diameter of the fibers is 0.5-30 microns, typical 2-7 microns
produced;
- Due to the smaller diameter of the fibers, it has a developed
internal volume and a larger surface area.
- Good moisture holding due to high internal volume
Characteristics may vary from manufacturer to manufacturer. From
process features.
42. Electrostatic properties
42
Filtering properties of layers
The main mechanism of fine filtration in medical masks and
respirators is electrostatic.
The following parameters influence the electrostatic properties
of filters:
- The ability of a material to obtain electrostatic properties;
- How it has been treated, as electrostatic properties are given
during processing;
- Surface area. Since the total charge and the number of
particles caught depend on it
The table shows an example of the difference in filtering
properties of a material before and after electrostatic
properties.
43. The general approach to the selection of filter
media for the layer
43
Filtering properties of layers
Basic parameters:
- Spun bond filter media have a larger fiber diameter than melt blown
filters. In other words, it is better to use melt-blown technology
to increase the filter surface area;
- Electrostatic properties depend on processing. They are not basic
for any material and strongly influence the filtration mechanism;
- Within a single process, characteristics such as fiber diameter,
density, and thickness of the filter may vary from manufacturer to
manufacturer;
- As the filter surface area grows as the fiber diameter decreases,
the structural properties of this material may decrease, limiting
the use of smaller diameter filtration technologies without
interfacing with materials created by other technologies.
Thus, the melt-blown technology is better suited for the fine
filtration layer due to the possibility of making filters with a large
surface area.
Both technologies are suitable for mechanical filtration.
For rough filtration, the spun bond technology is better suited as it
allows for larger filtration diameters. Also, materials with larger
fiber diameters have better design characteristics, which may be
important for maintaining the shape of the product and preventing
crushing.
45. Basic functions of hydrophobic layers
45
Hydrophobic properties of layers
Medical filters and masks require hydrophobic layers for the following
reasons:
- Many viruses and bacteria spread in droplets;
- Most biological contaminants have a water base (e.g. blood);
- Water clogging pores and obstructing breathing;
- Water is a media for bacteria to reproduce;
- In the case of an electrostatic filtration mechanism, water harms
the effectiveness of this mechanism.
In filters and masks, hydrophobic layers are required in the following
layers:
- Outer protective layer. Protects the filter or mask from water
penetration. Also, it protects the electrostatically filtered layer
against wetting. Protects the fluid accumulation layer from
premature filling;
- Intermediate hydrophobic layers protect the electrostatic filter
against wetting;
- It is possible to place an additional hydrophobic layer between the
electrostatic layer and the water accumulation layer;
- Perhaps the edges of the filter should be hydrophobic to prevent
moisture from entering between the filter and the face.
46. Materials
46
Hydrophobic properties of layers
Of the polymers used for nonwoven materials, polypropylene is one of
the most hydrophobic and penetration resistant liquids. The performance
of non-woven polypropylene filter media can be affected:
- The impurities in the material itself can increase wettability;
- Too large pores can cause the liquid to enter the filter;
- The insufficient or excessive surface roughness of the layer;
- Contamination leads to loss of hydrophobic properties;
- Filtered material accumulation leads to loss of hydrophobic
properties;
- Fine charged droplets may also adhere to hydrophobic electrostatic
layers;
- Mechanical damage may increase the wettability of the filter
Two or more electrostatic layers can be used, external or internal
electrostatic layers are used to capture small charged air droplets.
The hydrophobic properties of polypropylene can be enhanced by
additives or coatings.
48. Basic functions of hydrophilic layers
48
Hydrophilic properties of layers
Hydrophilic layers in masks and filters are needed for the following
reasons:
- The exhaled air contains water vapor, liquid droplets, saliva, and
sweat. They must be captured and drained from the face surface;
- For complete protection against exhalation (e.g. medical
applications), the exhaled air must be filtered through a medical
mask or respirator and the electrostatic filter must be protected
against fluid clogging
Thus, the following layers should have hydrophobic properties:
- A layer that stores moisture;
- The inner layer that comes into contact with the face;
- Additional layers are available to protect the base filter layer
from inhalation and exhalation.
The hydrophilic layers can be made of different materials. For the
inner layer, it is sufficient to drain the fluid into the moisture-
retaining layer. Moisture retention layers must have good absorbency.
49. Materials
49
Hydrophilic properties of layers
Different materials have different hydrophilic properties. These can be
either their basic properties or obtained through various additives to
the basic material or by creating coatings.
As hydrophilic materials, both with additives and based on basic
properties are usually used:
- Polyester;
- Rayon;
- Cotton;
- Polypropylene
Beyond hydrophobicity, some materials may accumulate moisture in the
fibers themselves. These are usually natural materials or special
synthetic materials.
For the inner layer adjacent to the face, it is not recommended to use
materials that can accumulate moisture in the fibers. They should draw
moisture away into the accumulation layer but do not retain it.
The inner layers may have large pores to improve moisture exchange with
the storage layer.
51. Main parameters
51
Ability to hold moisture
Moisture holding layers are used to hold the moisture generated by
breathing, saliva, sweat in masks, and respirators.
The best moisture holding properties are found in cotton. This is up to
30g per 1g of fabric. Of modern fabrics the nearest to cotton by these
functions of viscose based fabrics.
Most synthetic fabrics are unable to store large amounts of moisture.
Cotton wool and viscose can be used for the moisture-retaining layer.
On the other hand, the liquid is difficult to remove from cotton, this
creates a heat barrier even after a certain period.
After a certain amount of moisture in the layer, it may stop breathing
and begin to interfere with ventilation.
In some cases, polypropylene-based moisture absorbent materials are
used.
The strategy for choosing the material for the basic moisture-holding
layer can be structured as follows:
- Choosing a material that holds moisture;
- Ensuring the evaporation of moisture from this layer
Also, moisture-holding layers can be added to protect the main filter
layer.
In some cases this layer is perforated.
53. Main parameters
53
Applicability for skin contact (skin friendly)
Skin contact requires materials that do not cause damage to the face.
There are two approaches to creating nonwoven materials for skin
contact:
- Use of nonwoven materials based on natural materials such as cotton
or viscose derivatives;
- Additional processing of nonwoven synthetic materials
In many aspects, tissue comfort is a subjective parameter, but there
are common approaches. The use of hydrophobic or hydrophilic materials
is debatable. But in general, moisture in masks and respirators should
be removed from the face skin.
The following finishing methods are used to treat nonwoven synthetic
materials:
- Smoothing the surface;
- Softening
Softening is necessary because nonwovens have a rough structure.
Softening is either achieved by using special additives or by machining
to partially destroy the fabric.
- Perforation. Necessary for better moisture removal and air exchange.
Perforate such fabrics with either a needle press or hot air jets.
55. The materials for masks and respirators are also required in
terms of design
55
Construction properties of layers
The following requirements can be highlighted:
- Mask and filter materials must not break during normal use;
- Respiratory materials should be kept in shape to maintain volume for mouth
and nose air;
- Respirators must be able to restore their shape under normal use.
Compression of filters can lead to loss of filtering properties;
- The materials of masks and respirators must not be destroyed during use;
- The outer surfaces of masks and respirators must not lose their filtering
and hydrophobic properties when touched.
This is achieved by using materials with the necessary characteristics,
creating supporting layers of the right shape, making structures for bending
in the case of folding respirators.
56. Links
56
Construction properties of layers
https://journals.sagepub.com/doi/pdf/10.1177/1558925001OS-01000209
http://oa.upm.es/6671/1/ALVARO_RIDRUEJO_RODRIGUEZ.pdf
http://www.fibtex.lodz.pl/51_15_50.pdf
https://austinpublishinggroup.com/textile-engineering/fulltext/arte-v4-id1039.php
https://www.researchgate.net/publication/311869914_Experimental_Investigation_Of_Properti
es_Of_Polypropylene_And_Non-Woven_Spunbond_Fabric
http://blog.fdinonwovens.com/the-benefits-of-polypropylene-nonwoven-fabric
https://medcraveonline.com/JTEFT/spun-bonding-technology-and-fabric-properties-a-
review.html
https://www.iosrjournals.org/iosr-jpte/papers/Vol3-Issue5/B03050814.pdf
https://news.ncsu.edu/2020/04/a-necessary-filter/
57. Main parameters
57
Antibacterial protection
In the case of bacteria, masks and respirators work like mechanical filters. The size of bacteria
is always greater than 0.2 µm.
Bacteria can multiply under a mask and a moisture-holding layer. As water accumulates there. For
this reason, the accumulation of moisture on the skin is avoided and the operating time of the
mask or respirator is limited.
Various antibacterial agents in the case of masks and respirators are controversial. Because some
of these methods do not work in real conditions. Some working methods may be dangerous when used
in respiratory protection equipment.
The ability of masks and respirators to filter out bacteria is a basic standard. Testing for this
parameter is mandatory.
59. General description
59
Spunbond
Spunbond (spunlaid) is one of the processes for producing nonwovens.
In general, it has four stages:
- Filament spinning;
- Drawing;
- lay down;
- bonding
For use in medical masks and filters, the process can be described as
follows:
- The melt is extruded through small holes and fibers are formed;
- By air, the fibers are knocked into bundles;
- The bundles are randomly laid out on a moving surface to form a
fabric web;
- The fabric is then strengthened in some way. In the case of
nonwoven materials for filter applications, thermal and/or
pressurized sealing is best. Sealing with needles and flows of
water or air can impair the filtering properties of the material.
Although there are methods to supply heat with special solvents
In some cases, the fabric is perforated (for the inner layer).
61. General description
61
Melt blown
The Melt blown process has been specially developed for the
production of nonwovens with thin fibers. The principle of forming
individual threads is similar to the spun bond process. But because
the fibers are additionally stretched by hot airflow, it is possible
to produce fibers with a very small diameter.
After forming the fibers, they are randomly laid out to form the
fabric.
Beyond the possibility of producing fibers with smaller diameters for
the fabrics produced with this technology, reinforcement is not
required in many cases. With smaller fibers diameters, the fabric can
hold the shape.
Also, fibers with a diameter comparable to that of Spunbond can be
produced using this process. This technology can be used as a
replacement for filtering and adsorbing materials.
The diameter of melt-blown fibers is usually 2-7 µm but can be larger
- up to 15 µm, or smaller - up to 0.1 µm.
Thus, in filtration applications, melt-blown fabrics can also replace
Spunbond fabrics if rough filtration is required.
Both technologies are similar in basic processes and can be easily
integrated into the same process chain.
63. General description
63
Electrospinning
When solutions or melts in polymers are squeezed out in the
electric field due to the presence of moving charges in the
polymer electrostatic repulsion of the polymer molecules from each
other occurs. If the repulsion force is less than the keeping
forces of the polymer molecules in the melt or solution, no
rupture of the medium occurs. In this case, these forces
counteract the surface tension. This causes the polymer jet to
lengthen - a fiber is formed.
As the fiber solidifies, the charge migrates to the surface of the
fiber and the individual fibers are pushed away from each other,
which allows for uniform spreading without forming too dense
stretches.
Electrospinning will produce fibers with diameters of 0.1-0.3 µm
and a homogeneous fiber.
One of the possible applications of nonwoven materials developed
with the help of electrospinning is filtration.
However, this technology has not yet become widespread in medical
filters (masks and respirators) for several reasons.
On the one hand, the process is more complex than described and it
is difficult to design equipment based on it, on the other hand,
there are limitations on the use of this type of nonwoven material
in practice.
64. General description
64
Electrospinning
Nonwovens based on electrospinning for filtration.
Advantages:
- Small pore size - provides better fine filtration;
- Fabric homogeneity;
- Slipping of airflow or liquid in thin filtration threads reduces
pressure drop on filter sides;
- Fabric properties begin to approach those of solid material,
allowing it to hold its shape. The high density of the fibers is
implied;
- Electrostatic filtration mechanism can be used
Disadvantages:
- Pre-filtration is required. Particles larger than pore diameter
quickly fill the top layer of the filter and the process stops;
- The most suitable materials for the filter require spraying from
the melt, not the solution, due to the absence of suitable
solvents;
- Lose the flexibility of woven materials, in thin layers they are
particularly brittle, which imposes restrictions on their use in
wearable materials;
- Quickly filled with moisture due to the best capillary effects
in the absence of through-flows;
- Support structures are required to maintain form and integrity
under physical effects
65. General description
65
Electrospinning
Possible use in surgical masks and respirators.
Although the manufacturers of electrospinning (E) equipment have
announced that it is possible to use surgical masks and
respirators as a filter media, there is no real application yet.
How it is possible to use it:
- Adding a layer of fine filtration. For example, an improvement
when filtering viruses. For example, layer contracts SMES,
SMEMS, ME, MEM and similar;
- Due to the peculiarities of the technology, it is possible to
apply pointwise on individual sections of products or on
products with complex shapes. For example, on cups of
respirators;
- Drainage of moisture from respirators. Due to good capillary
effects, such fabrics can drain moisture to the surface from the
layer of moisture accumulation if there is no airflow through
them (no clogging particles);Perhaps best suited for general
applications where there are no requirements for long filter
life in heavily contaminated environments and fluids.
Electrospinning technology should be taken into account for the
potential development of new filter devices. But in general,
because filters are complex multi-layer structures where layers
have different functions, this technology will not completely
replace them, but it is promising to create layers with new
characteristics.
67. 67
Spunbond, melt blown, electrospinning
Technology Spunbond Meltblown Electrospinning
Fiber diameter, µm 15-35 до 15
До 1 2-7
До 0.1 0.05-0.4
Filtering level Rough Fine and ultrafine by
electrostatics
Ultrafine due to
mechanical filtration
and electrostatics
Extra hardening of
fabrics
In most cases, it is
required
It's not always
necessary
No need.
Tissue behavior Behaving like fabric is
flexible enough
It behaves like fabric
in thin layers. In
thick layers it loses
flexibility (at high
density)
It behaves like fabric
only in very thin
layers. In thick
layers, it begins to
show the properties of
a solid material (at
high density)
Materials based on the meltblown process are well suited for creating different layers in modern
filters (with different characteristics of the source material).
However, building filters based on materials created with different technologies is more
productive. Both from individual material layers and composite layers.
68. General description
68
SMS concept
Fabrics based on melt-blown polypropylene are formed by thin
fibers, which on the one hand provide good filtration ability, and
on the other hand, reduces the strength of such materials at the
density required for good airflow. Also, fine filters can quickly
clog with large particles and lose their filtering properties.
Fabrics based on spun-bonded polypropylene are formed by thin
fibers but with a larger diameter than melt-blown fabrics. On the
one hand, this gives better construction characteristics, on the
other hand, it allows the production of materials for the
filtration of large particles.
To combine material properties, a composite material concept has
been developed based on these technologies.
Since both types of fabrics are based on the same thermoplastic
polymer, these fabrics can be easily welded into one fabric.
There are many options. These are composites based on the same
fabric type, for example, SS or SSS (spun-bonded + spun-bonded).
But the most popular composites are SMS (spun-bonded + melt-blown
+ spun-bonded) and more complex ones.
69. 69
SMS concept
In SMS composites, layers can perform the following functions:
- S layers are designed for rough filtering;
- S hydrophobic layers are designed to protect M layers from
wetting with water;
- S hydrophilic layers are designed to remove moisture from the
body;
- S perforated layers are designed to remove heat and water vapor;
- M layers are designed for fine filtration
There are many options for such composites. SMS, SSMS, SM, SMMMS,
and others.
In addition, polyethylene and/or hydrophilic additives are often
added to S layers to give additional properties.
The disadvantages of such fabrics are:
- Difficulty in producing multilayer structures;
- Introduction into layers of materials without thermoplastic
properties;
- Difficulty in introducing some additives. For example, activated
carbon;
- Difficulty in modifying M layers to give them electrostatic
properties.
The last disadvantage is the main one. Since the electrostatic
properties of M layers provide better filtration of fine
particles. For this reason, separate M layers are common in
various products.
71. General description
71
Charging
In the case of catching fine charged particles due to electrostatic
effects, it is necessary to give appropriate properties to the
fabric.
This is applicable for technologies to produce small diameter fibers.
For this purpose, the surface of the fibers is "charged" in some way.
The effect can occur in a strong electric field. But the best
efficiency is provided by corona discharge systems.
In the production of electret non-woven fibers, no "charging" is
possible anywhere in the process. The process of changing
electrostatic properties is not very suitable for molten polymers and
after cooling. Optimal placement of corona discharge units at the
points where the polymer solidifies but is not cooled to room
temperature. Other options are possible.
Active search for various additives to the basic materials to enhance
the effect.
"Charging" polypropylene works better on individual layers. When
creating SMS constructions, it is difficult.
Used for the main filter layer.
Several layers are possible. Managing these characteristics may allow
you to create new types of filters.
73. General description
73
Additives
There are many different additives for nonwovens. You can list
them:
- Additives to give hydrophilic properties to polypropylene;
- To reduce or increase electrostatic properties;
- Additives for changing mechanical properties;
- Other polymers for changing properties;
- Additives to protect the polymer from UV;
- Additives for giving bactericidal properties;
- Various coatings
There may be a lot of options.
https://www.researchgate.net/publication/287080124_Surface_modification_of_polypro
pylene_films_using_hydrophilic_additives
https://patents.google.com/patent/EP2411061A1/en
https://www.sciencedirect.com/science/article/pii/S030438941730763X
https://www.adeka.co.jp/en/chemical/products/plastic/knowledge_04.html
https://www.plastic-additives.com/product/break-thru/downloads/additives-post-
treatment-modification-pigments_fillers.pdf
http://oil.vcdcenter.com/wp-content/uploads/2018/10/Additives-for-PolyolefinsGetting-
the-Most-out-of-Polypropylene-Polyethylene-and-TPO-2015.pdf
74. General description
74
Ultrasonic welding
Ultrasonic welding is one way of joining nonwoven materials.
It is used for:
- Hardening of nonwoven fabrics (fusion of individual fibers on the whole area or along
contours;
- Joining individual layers of nonwoven materials in a single piece. Usually along a
contour or at individual points;
- Cutting the fabric;
- Cutting individual items.
It is used to replace cords, adhesives, joining at increased temperatures.
The principle of operation is based on the partial melting of thermoplastic polymers on
the surface, at the point of contact, etc. This ensures the connection of individual layers.
Now it is actively applied at the manufacture of medical masks, respirators, and other
products from nonwoven materials.
77. 77
New materials
One of the directions for creating new and competitive
constructions is the use of new materials and technologies
One of the promising materials for PPE is membrane materials based on
fluoropolymers.
These materials have hydrophobic properties, are thermoplastic - that
allows to create on their basis nonwoven materials from thin fibers and
to combine with other materials. They are already used in clothing and
are mass produced.
Limitations of their use are the price (higher by about 5 times than
other materials) and the inability to create electrostatic filters on
the damage of modern technology. Filtration in such materials can be
done only mechanically.
For respirators and other means of respiratory protection, the use of
thin mechanical filters is difficult due to their reduced breathing air
permeability.
However, as additional hydrophobic and filtering layers, they can be
used.
https://www.dhafilter.com/face-masks/
https://www.teflexgasket.com/ptfe-membrane.html
https://www.sukopolymer.com/ptfe-nano-masks-a-new-trend-of-future-masks/
https://www.cleanroomtechnology.com/news/article_page/Air_filtration_Advantages_of_PTFE_
materials/153455
78. 78
New materials
Modern production technologies
The possibility of making reusable metal filters using additive
manufacturing methods has recently been demonstrated.
Similar ideas were offered for the creation of filtering materials on
the basis of 3D printing polymeric materials, however, it is
unprofitable from the economic point of view.
However, in the case of printing by metals, it is possible to create
reusable filters. Suitable for clearing, sterilization, etc.
Such products can be established as additional filters, filters on
valves.
Although the main niche for such technologies is cartridge filters for
other types of respirators.
https://3dprintingindustry.com/news/exone-and-university-of-pittsburgh-produce-promising-
reusable-respirators-using-3d-printed-metal-filters-171117/
79. 79
Contact us: Fine Systems Technologies, LLC
Russia
Vladislav Troshin (CEO)
troshin@fine-systems.tech
info@fine-systems.tech
www.fine-systems.tech
+7 929 509 44 89 (RU)