This document discusses noise control in the workplace. It begins by defining noise and classifying it as a physical hazard that can cause permanent hearing damage. It then outlines relevant noise regulations, including permissible exposure limits of 90dB(A) continuously and 115dB(A) at any time according to the Factories and Machinery (Noise Exposure) Regulation 1989.
The document presents the hierarchy of noise control strategies, from controlling noise at the source to reducing exposure of employees. It provides examples of engineering controls like modifying equipment to reduce impact or aerodynamic noise, using absorptive materials, and isolating vibrations. Plant layout considerations and substituting quieter processes, equipment, and materials are also summarized. The focus is
The document discusses various sources of noise from HVAC systems and methods for noise control. It describes common noise sources such as fans, compressors, pumps and ductwork. It then explains approaches to reduce noise such as using resilient hangers and mounts, lining ducts, sealing penetrations, and selecting quieter equipment. Specific topics covered include estimating noise from fans, diffusers, duct shapes and breaks in ductwork.
Noise control is important for many products like computer hard drives and appliances. Sound is defined as vibrations stimulating the ear, and can propagate as longitudinal or transverse waves. Sound level is measured in decibels on a logarithmic scale, where a small increase represents a large increase in sound energy. Sources of noise include industrial sources like transportation and non-industrial sources like traffic. Methods to reduce noise include improving engineering to lower noise levels, establishing regulations for manufacturers, and reducing vibration at sources.
This document provides an introduction to noise control concepts and methods. It outlines when noise control is required according to legal exposure limits. Key aspects of noise control covered include noise risk assessment, identifying excessive noise exposures, and implementing controls following the hierarchy of control from elimination to administrative controls to personal protective equipment. Engineering controls for noise reduction are discussed in terms of controlling noise at the source, transmission path, and receiver. Methods like insulation, barriers, and enclosure of noise sources are presented. The importance of noise monitoring and a multifaceted approach to noise control following the hierarchy are emphasized.
The document provides guidelines for properly measuring the noise level of air conditioning units. It begins by outlining the importance of acoustic comfort and international noise level standards. It then lists a multi-step process to measure environmental noise, duct borne noise, and noise from indoor units. Some key steps include turning off all HVAC units to measure ambient noise levels, measuring at distances from supply vents and return grilles, and using acoustic insulation and special attenuators to reduce noise as needed. Proper documentation of noise measurements before and after any reductions is recommended. Achieving adequate noise control can help earn additional LEED points for indoor environmental quality.
This document discusses various canal cleaning techniques, including hand instrumentation and rotary nickel-titanium techniques. It describes different types of endodontic instruments such as barbed broaches, K-files, Hedstrom files, and rotary instruments like ProTaper files, Race files, and ultrasonic/sonic instruments. It provides details on the manufacturing, uses, and modifications of various instruments used for shaping and cleaning root canals.
We, Ecotone Acoustic Enclosure are India’s most reliable manufacturers of Acoustic products for Noise Control, NVH Test Chambers, Acoustic, Architectural, Auditoriums, Theatres, Conference halls, Gymnasium halls, Offices, Banquet halls, Design and Set-up of Recording Studios, Listening rooms, Home Theatres etc.
Ecotone Systems is the largest manufacturers and providers of Acoustic wall and ceiling products that provide Architects and Building owners an extensive range of products to chose from, which suits their aesthetic as well as acoustic requirements. Ecotone Acoustic Enclosure strives to help its customers enjoy the best ambience, at the same time minimizing its environmental impact as much as possible by providing sustainable, innovative and high-performance solutions for todays and tomorrows noise problems.
This document discusses noise levels produced by aggregate processing equipment like bulldozers, loaders, crushers, and dump trucks. It notes that most equipment creates noise between 70-100dB, similar to tractors, and some alarms can reach 110dB. It emphasizes the importance of monitoring noise levels, establishing safe operating levels regulated by organizations like MSHA and OSHA, and using various techniques to minimize noise, such as barriers, vegetation, and equipment maintenance. Distance, terrain, vegetation, weather, and other factors influence noise levels, so impacts must be evaluated on an individual basis.
This document discusses speeds used in operative dentistry. It defines speed as revolutions per minute and classifies speeds as low (<12,000 rpm), medium (12,000-200,000 rpm), or high (>200,000 rpm). Lower speeds provide better tactile sense but slower cutting, while higher speeds cut faster but with less tactile control and increased risk of overheating. Different handpieces and burrs are suited to low, medium, and high speeds. The appropriate speed depends on the procedure and balancing factors like cutting rate, torque, tactile feedback, and heat production.
The document discusses various sources of noise from HVAC systems and methods for noise control. It describes common noise sources such as fans, compressors, pumps and ductwork. It then explains approaches to reduce noise such as using resilient hangers and mounts, lining ducts, sealing penetrations, and selecting quieter equipment. Specific topics covered include estimating noise from fans, diffusers, duct shapes and breaks in ductwork.
Noise control is important for many products like computer hard drives and appliances. Sound is defined as vibrations stimulating the ear, and can propagate as longitudinal or transverse waves. Sound level is measured in decibels on a logarithmic scale, where a small increase represents a large increase in sound energy. Sources of noise include industrial sources like transportation and non-industrial sources like traffic. Methods to reduce noise include improving engineering to lower noise levels, establishing regulations for manufacturers, and reducing vibration at sources.
This document provides an introduction to noise control concepts and methods. It outlines when noise control is required according to legal exposure limits. Key aspects of noise control covered include noise risk assessment, identifying excessive noise exposures, and implementing controls following the hierarchy of control from elimination to administrative controls to personal protective equipment. Engineering controls for noise reduction are discussed in terms of controlling noise at the source, transmission path, and receiver. Methods like insulation, barriers, and enclosure of noise sources are presented. The importance of noise monitoring and a multifaceted approach to noise control following the hierarchy are emphasized.
The document provides guidelines for properly measuring the noise level of air conditioning units. It begins by outlining the importance of acoustic comfort and international noise level standards. It then lists a multi-step process to measure environmental noise, duct borne noise, and noise from indoor units. Some key steps include turning off all HVAC units to measure ambient noise levels, measuring at distances from supply vents and return grilles, and using acoustic insulation and special attenuators to reduce noise as needed. Proper documentation of noise measurements before and after any reductions is recommended. Achieving adequate noise control can help earn additional LEED points for indoor environmental quality.
This document discusses various canal cleaning techniques, including hand instrumentation and rotary nickel-titanium techniques. It describes different types of endodontic instruments such as barbed broaches, K-files, Hedstrom files, and rotary instruments like ProTaper files, Race files, and ultrasonic/sonic instruments. It provides details on the manufacturing, uses, and modifications of various instruments used for shaping and cleaning root canals.
We, Ecotone Acoustic Enclosure are India’s most reliable manufacturers of Acoustic products for Noise Control, NVH Test Chambers, Acoustic, Architectural, Auditoriums, Theatres, Conference halls, Gymnasium halls, Offices, Banquet halls, Design and Set-up of Recording Studios, Listening rooms, Home Theatres etc.
Ecotone Systems is the largest manufacturers and providers of Acoustic wall and ceiling products that provide Architects and Building owners an extensive range of products to chose from, which suits their aesthetic as well as acoustic requirements. Ecotone Acoustic Enclosure strives to help its customers enjoy the best ambience, at the same time minimizing its environmental impact as much as possible by providing sustainable, innovative and high-performance solutions for todays and tomorrows noise problems.
This document discusses noise levels produced by aggregate processing equipment like bulldozers, loaders, crushers, and dump trucks. It notes that most equipment creates noise between 70-100dB, similar to tractors, and some alarms can reach 110dB. It emphasizes the importance of monitoring noise levels, establishing safe operating levels regulated by organizations like MSHA and OSHA, and using various techniques to minimize noise, such as barriers, vegetation, and equipment maintenance. Distance, terrain, vegetation, weather, and other factors influence noise levels, so impacts must be evaluated on an individual basis.
This document discusses speeds used in operative dentistry. It defines speed as revolutions per minute and classifies speeds as low (<12,000 rpm), medium (12,000-200,000 rpm), or high (>200,000 rpm). Lower speeds provide better tactile sense but slower cutting, while higher speeds cut faster but with less tactile control and increased risk of overheating. Different handpieces and burrs are suited to low, medium, and high speeds. The appropriate speed depends on the procedure and balancing factors like cutting rate, torque, tactile feedback, and heat production.
The DD 2X4 is a portable downdraft table that captures fumes, smoke, or dust from industrial activities. It features a flexible work surface, high air capture velocity, and multi-stage filters. It can be configured for different applications like welding, grinding, and painting with options like side walls, carbon filters, and hoods. The table is compact, plug-and-play, and helps improve indoor air quality.
The document discusses various sources of noise from internal combustion engines and methods to control engine noise. It identifies the main sources of engine noise as aerodynamic noise from air and exhaust flow, combustion noise from pressure fluctuations during combustion, and mechanical noise from engine component vibration. It then discusses noise from the intake system, exhaust system, cooling system, and remedial noise control measures like improving component design and insulation.
This document summarizes the features and specifications of the BNP Double 65 Pressure Blast Cabinet. The cabinet uses pressurized air to blast surfaces with abrasive media for cleaning, stripping, and finishing. It features dual work stations, integrated controls, safety interlocks, and lighting for visibility. Specifications include dimensions, required air flow and electrical requirements, available nozzles and media reclaim systems.
The document discusses noise reduction within industrial settings and outlines different types of silencers that can be installed on flue systems to reduce noise. It notes that prolonged high noise levels can cause permanent hearing damage. Absorption silencers reduce higher frequencies by using materials like mineral wool to absorb sound, while resonance silencers are designed to neutralize low frequencies from sources like diesel engines and boilers. Combination silencers provide noise reduction across all frequencies. When selecting a silencer system, factors like single-wall design, integrated silencers, easy connections, and thermal expansion should be considered to minimize vibrations and costs.
This document provides an overview of acoustical analysis services provided by GHD, including noise and vibration monitoring, modeling, compliance testing, and building acoustic design. Key services mentioned include noise impact studies, construction noise monitoring, noise modeling using CadnaA software, pump vibration analysis, generator noise assessments, and testing for sound insulation and reverberation in buildings. Case studies described noise modeling for industrial facilities and emergency generators, as well as building acoustic investigations and testing.
This document provides information about Sonic Air Systems, which manufactures blowers, air knives, and other air handling equipment. It discusses their wide range of products for applications like drying, cooling, coating control, and more. It also describes their global sales and service network and highlights their product innovation and ability to provide customized solutions. The document emphasizes Sonic's focus on energy efficiency and cost savings compared to other air supply methods like compressed air. It provides examples of how Sonic products are used across various industries like automotive, food and beverage, construction, and more.
Endodontic instruments /certified fixed orthodontic courses by Indian dental...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.
Sonobaffles are acoustic panels produced by Sontext to reduce noise and echoes in large indoor spaces. They are suspended from ceilings using wires or chains and come in standard sizes of 1200x600mm, 1200x1200mm, or 2400x1200mm, or can be custom made. Sonobaffles contain a sound absorbing material encased in a decorative fabric and have been tested to achieve a Noise Reduction Coefficient of up to 0.80, making them suitable for applications in offices, convention centers, pools, factories and more.
The document summarizes a BNP 65 Suction Blast Cabinet. It features safety gloves, lighting, and interlocks. It can clean, peen, deburr, and finish parts efficiently. It includes a blast gun, regulator, and blow-off gun. Popular accessories include an adjustable gun mount, filters, and a tumble basket. Specifications include dimensions, electrical requirements, and ordering information for models with different airflow capacities and dust collection options.
This document discusses key acoustic factors to consider for effective communication in classrooms. It outlines that the distance between speakers and listeners, signal-to-noise ratio, reverberation, and physical barriers all impact sound transmission. Early reflections contribute positively to the effective speech signal while late reflections and background noise contribute to the effective noise level. The proportion of speech signal that exceeds the effective noise level allows an estimate of speech perception regardless of individual characteristics. Reverberation time determines the equivalent noise level from late reflections.
Noise pollution in industries and harbour Pavithra Pavi
The document discusses various sources and effects of noise pollution. It identifies two main categories of noise pollution sources: industrial sources like machines and non-industrial sources like vehicles and construction. Major noise sources in industries are identified as machines, engines, and fluid flows. The document provides noise exposure limits and guidelines. It discusses options to control noise pollution at the source, transmission path, and receiver. The health and environmental effects of noise pollution are also summarized.
Noise levels in wood product manufacturing workplaces often exceed safe limits, putting workers at risk of permanent, irreversible hearing loss. Common sources of loud noise include saws, routers, presses and sanders. Prolonged exposure to noise over 85 dB(A) can damage hearing. Employers must control noise risks through steps like installing mufflers, limiting exposure time, and providing protective gear. Regular audits ensure safety controls stay effective.
Noise pollution presentation by Muhammad Fahad Ansari 12IEEM14fahadansari131
The document discusses noise pollution in the textile industry. It provides information on sources of noise pollution, effects of noise at different decibel levels, and noise levels from machines used in textile wet processing, weaving, and spinning sectors. It also discusses some methods that can be used to control noise pollution in textile industries, such as using anti-vibration rubber sheets, vibration isolators, sound absorbers, proper maintenance, and replacing metal parts. The overall noise level for human comfort is between 40-60 decibels.
Basic endodontics instruments its use in cleaning and shapeingSarahdentist
This document discusses root canal instrumentation and irrigation. It begins by outlining the steps of root canal treatment which are cleaning, shaping, and obturation of the root canal system. It then discusses various instruments used for cleaning and shaping such as files, broaches, reamers, and drills. The document describes the standardization of root canal instruments based on factors like length, diameter, taper, tip angle, and color coding. It also discusses modifications made to traditional instruments with new materials like nickel-titanium. Finally, it outlines various irrigation methods and solutions used to cleanse the root canal including manual irrigation with needles as well as newer machine-assisted techniques.
This document provides a classification and overview of endodontic instruments. It discusses diagnostic instruments used to examine the dental pulp, as well as instruments for accessing canals, exploring canals, extirpating pulp, and enlarging root canals. Key points include the standardized sizing of root canal files according to ISO guidelines, modifications made to traditional K-files and H-files to increase flexibility and cutting efficiency, and the use of different materials like carbon steel for initial penetration of narrow canals. The document provides details on various instruments and their functions at different stages of root canal treatment.
This document summarizes the specifications and features of the BNP Double 220 Pressure Blast Cabinet. The cabinet features dual blast stations, tungsten carbide nozzles, safety interlocks, lighting, and various optional accessories. It uses a high-efficiency 2.0 cubic foot pressure vessel and reclaimer system to blast parts and continuously recycle media, increasing production rates up to 300%.
This document summarizes the standardization and classification of endodontic files. It discusses how endodontic hand files were first standardized by Ingle and LeVine to have a constant taper and diameter increments of 5 or 10. Files are now numbered from 10-140 based on tip diameter in hundredths of a millimeter. The shaft extends 16mm from the tip and tapers 0.32mm. Common file types discussed include K-files, K-flex, Flex-R, Hedstroem, Safety H, Hyflex, Unifiles, and S-files. Each file type has a unique cross-section or design that provides specific advantages for root canal shaping and cleaning.
El documento resume los resultados de una exploración de tiendas que ofrecen muebles hechos con fibras naturales. Visitaron IKEA y dos tiendas llamadas Charo Decoraciones y Charo Exteriores. Encontraron una variedad de sillas y muebles hechos de materiales como mimbre, bambú, ratán, fibra de plátano y lana. Algunos muebles se pueden personalizar en tamaño y color.
Sunil Kumar Chauhan is seeking a new challenging role that allows him to utilize his 11+ years of experience in instrumentation and electrical engineering. He is currently an engineer at Continental India Ltd where he maintains automation systems and plant equipment. Chauhan has expertise in PLC programming, drives, sensors, process improvement, and executing automation projects. He has experience working with Siemens, Allen Bradley, and Yokogawa systems. Some of his project experience includes commissioning a power plant DCS, paper machine, and industrial furnaces.
The DD 2X4 is a portable downdraft table that captures fumes, smoke, or dust from industrial activities. It features a flexible work surface, high air capture velocity, and multi-stage filters. It can be configured for different applications like welding, grinding, and painting with options like side walls, carbon filters, and hoods. The table is compact, plug-and-play, and helps improve indoor air quality.
The document discusses various sources of noise from internal combustion engines and methods to control engine noise. It identifies the main sources of engine noise as aerodynamic noise from air and exhaust flow, combustion noise from pressure fluctuations during combustion, and mechanical noise from engine component vibration. It then discusses noise from the intake system, exhaust system, cooling system, and remedial noise control measures like improving component design and insulation.
This document summarizes the features and specifications of the BNP Double 65 Pressure Blast Cabinet. The cabinet uses pressurized air to blast surfaces with abrasive media for cleaning, stripping, and finishing. It features dual work stations, integrated controls, safety interlocks, and lighting for visibility. Specifications include dimensions, required air flow and electrical requirements, available nozzles and media reclaim systems.
The document discusses noise reduction within industrial settings and outlines different types of silencers that can be installed on flue systems to reduce noise. It notes that prolonged high noise levels can cause permanent hearing damage. Absorption silencers reduce higher frequencies by using materials like mineral wool to absorb sound, while resonance silencers are designed to neutralize low frequencies from sources like diesel engines and boilers. Combination silencers provide noise reduction across all frequencies. When selecting a silencer system, factors like single-wall design, integrated silencers, easy connections, and thermal expansion should be considered to minimize vibrations and costs.
This document provides an overview of acoustical analysis services provided by GHD, including noise and vibration monitoring, modeling, compliance testing, and building acoustic design. Key services mentioned include noise impact studies, construction noise monitoring, noise modeling using CadnaA software, pump vibration analysis, generator noise assessments, and testing for sound insulation and reverberation in buildings. Case studies described noise modeling for industrial facilities and emergency generators, as well as building acoustic investigations and testing.
This document provides information about Sonic Air Systems, which manufactures blowers, air knives, and other air handling equipment. It discusses their wide range of products for applications like drying, cooling, coating control, and more. It also describes their global sales and service network and highlights their product innovation and ability to provide customized solutions. The document emphasizes Sonic's focus on energy efficiency and cost savings compared to other air supply methods like compressed air. It provides examples of how Sonic products are used across various industries like automotive, food and beverage, construction, and more.
Endodontic instruments /certified fixed orthodontic courses by Indian dental...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.
Sonobaffles are acoustic panels produced by Sontext to reduce noise and echoes in large indoor spaces. They are suspended from ceilings using wires or chains and come in standard sizes of 1200x600mm, 1200x1200mm, or 2400x1200mm, or can be custom made. Sonobaffles contain a sound absorbing material encased in a decorative fabric and have been tested to achieve a Noise Reduction Coefficient of up to 0.80, making them suitable for applications in offices, convention centers, pools, factories and more.
The document summarizes a BNP 65 Suction Blast Cabinet. It features safety gloves, lighting, and interlocks. It can clean, peen, deburr, and finish parts efficiently. It includes a blast gun, regulator, and blow-off gun. Popular accessories include an adjustable gun mount, filters, and a tumble basket. Specifications include dimensions, electrical requirements, and ordering information for models with different airflow capacities and dust collection options.
This document discusses key acoustic factors to consider for effective communication in classrooms. It outlines that the distance between speakers and listeners, signal-to-noise ratio, reverberation, and physical barriers all impact sound transmission. Early reflections contribute positively to the effective speech signal while late reflections and background noise contribute to the effective noise level. The proportion of speech signal that exceeds the effective noise level allows an estimate of speech perception regardless of individual characteristics. Reverberation time determines the equivalent noise level from late reflections.
Noise pollution in industries and harbour Pavithra Pavi
The document discusses various sources and effects of noise pollution. It identifies two main categories of noise pollution sources: industrial sources like machines and non-industrial sources like vehicles and construction. Major noise sources in industries are identified as machines, engines, and fluid flows. The document provides noise exposure limits and guidelines. It discusses options to control noise pollution at the source, transmission path, and receiver. The health and environmental effects of noise pollution are also summarized.
Noise levels in wood product manufacturing workplaces often exceed safe limits, putting workers at risk of permanent, irreversible hearing loss. Common sources of loud noise include saws, routers, presses and sanders. Prolonged exposure to noise over 85 dB(A) can damage hearing. Employers must control noise risks through steps like installing mufflers, limiting exposure time, and providing protective gear. Regular audits ensure safety controls stay effective.
Noise pollution presentation by Muhammad Fahad Ansari 12IEEM14fahadansari131
The document discusses noise pollution in the textile industry. It provides information on sources of noise pollution, effects of noise at different decibel levels, and noise levels from machines used in textile wet processing, weaving, and spinning sectors. It also discusses some methods that can be used to control noise pollution in textile industries, such as using anti-vibration rubber sheets, vibration isolators, sound absorbers, proper maintenance, and replacing metal parts. The overall noise level for human comfort is between 40-60 decibels.
Basic endodontics instruments its use in cleaning and shapeingSarahdentist
This document discusses root canal instrumentation and irrigation. It begins by outlining the steps of root canal treatment which are cleaning, shaping, and obturation of the root canal system. It then discusses various instruments used for cleaning and shaping such as files, broaches, reamers, and drills. The document describes the standardization of root canal instruments based on factors like length, diameter, taper, tip angle, and color coding. It also discusses modifications made to traditional instruments with new materials like nickel-titanium. Finally, it outlines various irrigation methods and solutions used to cleanse the root canal including manual irrigation with needles as well as newer machine-assisted techniques.
This document provides a classification and overview of endodontic instruments. It discusses diagnostic instruments used to examine the dental pulp, as well as instruments for accessing canals, exploring canals, extirpating pulp, and enlarging root canals. Key points include the standardized sizing of root canal files according to ISO guidelines, modifications made to traditional K-files and H-files to increase flexibility and cutting efficiency, and the use of different materials like carbon steel for initial penetration of narrow canals. The document provides details on various instruments and their functions at different stages of root canal treatment.
This document summarizes the specifications and features of the BNP Double 220 Pressure Blast Cabinet. The cabinet features dual blast stations, tungsten carbide nozzles, safety interlocks, lighting, and various optional accessories. It uses a high-efficiency 2.0 cubic foot pressure vessel and reclaimer system to blast parts and continuously recycle media, increasing production rates up to 300%.
This document summarizes the standardization and classification of endodontic files. It discusses how endodontic hand files were first standardized by Ingle and LeVine to have a constant taper and diameter increments of 5 or 10. Files are now numbered from 10-140 based on tip diameter in hundredths of a millimeter. The shaft extends 16mm from the tip and tapers 0.32mm. Common file types discussed include K-files, K-flex, Flex-R, Hedstroem, Safety H, Hyflex, Unifiles, and S-files. Each file type has a unique cross-section or design that provides specific advantages for root canal shaping and cleaning.
El documento resume los resultados de una exploración de tiendas que ofrecen muebles hechos con fibras naturales. Visitaron IKEA y dos tiendas llamadas Charo Decoraciones y Charo Exteriores. Encontraron una variedad de sillas y muebles hechos de materiales como mimbre, bambú, ratán, fibra de plátano y lana. Algunos muebles se pueden personalizar en tamaño y color.
Sunil Kumar Chauhan is seeking a new challenging role that allows him to utilize his 11+ years of experience in instrumentation and electrical engineering. He is currently an engineer at Continental India Ltd where he maintains automation systems and plant equipment. Chauhan has expertise in PLC programming, drives, sensors, process improvement, and executing automation projects. He has experience working with Siemens, Allen Bradley, and Yokogawa systems. Some of his project experience includes commissioning a power plant DCS, paper machine, and industrial furnaces.
Abbiamo creato un video e delle strategie di marketing online, integrando diversi social network per generare "Social Testimonial" su Facebook, Instagram e Twitter.
Il lavoro è stato presentato presso l'UnivPM, al corso di Internet & Marketing tenuto dalla professoressa Pascucci.
(La presentazione contiene Fonts particolari per una corretta visualizzazione dei contenuti)
This document provides a step-by-step guide for high school students to follow when applying to colleges. It includes instructions on using the school's Naviance account to organize the application process, request letters of recommendation, add colleges to apply to lists, match Common App accounts, and submit transcript release forms. The document emphasizes starting early, meeting deadlines, and ensuring all application materials like test scores and transcripts are sent to schools directly. It also answers some frequently asked questions about following the steps, application timelines, and accessing Naviance features.
This document summarizes a study estimating geo-mechanical properties of reservoir rocks from well log data. The study presents a method to predict shear wave velocity from compressional wave velocity, porosity, and shale content when direct shear wave measurements are unavailable. Elastic properties including Poisson's ratio, shear modulus, bulk modulus, and Young's modulus are then calculated. These properties allow evaluation of formation strength and prediction of safe production rates without sand production. The results show shear and compressional wave velocities are linearly related. Calculated combined modulus of strength and shear modulus to compressibility ratio values indicate the formations can generally be produced safely below an optimum flow rate without significant sand production risks.
The document describes a simulation of heat transfer into a copper ball heated by a torch. It derives equations to model the temperature change over time considering convection and optionally radiation heat transfer. The simulation is performed in MATLAB considering first only convection, then convection and radiation. The results show that including radiation lowers the final steady state temperature from 152°C to 131°C and decreases the settling time from 4540 seconds to 3340 seconds.
Dr. James Wellington Crane was a medical doctor and professor born in 1877 who had a distinguished career in medicine. He practiced in small towns in Ontario before joining the faculty at the University of Western Ontario where he taught pharmacology and served as acting dean. In retirement, he devoted himself to alumni work and developed an arboretum on his property named Kelligrew, which is now a conservation area. Crane had wide-ranging interests including collecting books, trees, and helping his students and community. He passed away in 1959 at the age of 82, leaving a lasting legacy through his conservation efforts, teaching, and support of others.
This document contains credits for photos used in a Haiku Deck presentation, listing the names of 9 photographers and their photo sources. It concludes by encouraging the reader to create their own Haiku Deck presentation.
Matthew Hartman has over 20 years of experience as a technician and workshop manager for various automotive brands such as VW, Honda, Audi, and Mazda. He is currently the manager of a team of 4 fitters at National Tyres Borehamwood. Previously, he managed a team of 10 technicians as manager of Kwik-fit in Bushey. Hartman is reliable, adaptable, and capable of working independently as well as part of a team. He has strong skills in diagnostics, maintenance, inventory systems, and leading others.
Prospective clinical trial of traction device-assisted endoscopic submucosal ...Goto Pablo
1) The study evaluated the efficacy and safety of a new traction device called the S-O clip for assisting endoscopic submucosal dissection (ESD) of large superficial colorectal tumors.
2) 27 patients underwent ESD with assistance from the S-O clip, while 23 patients underwent conventional ESD without the clip.
3) ESD with the S-O clip took less time on average (37.4 minutes vs 67.1 minutes for conventional ESD) and achieved en bloc resection in all cases without complications, demonstrating it is a safe and efficient method for resecting large superficial colorectal tumors.
Collecting quality clinical cases is a priotity to document more evidence in medicine, providing a wide data-base allowing research, tuition and high quality reported cases.
The document summarizes an ANSYS model and analysis to generate a chart of stress concentration factor (Kt) in a notched rectangular bar with a varying notch radius (r). The model is symmetric about two axes, with a width (w) to depth (d) ratio of 3, Poisson's ratio of 0.3, and applied pressure of -1 MPa. Meshes from coarse to fine were used, with stress changing by 2.4% indicating reasonable convergence. Results include deformed shape, stress contour, and a plot of Kt versus r/d with w/d held constant at 3.
This document discusses noise control measures for HVAC systems. It begins by outlining the effects of noise on humans and some common mistakes in noise control. It then describes basic noise control methods like absorption, damping, decoupling, mass, and flow control. Specific examples of decoupling measures like resilient channels, clips, and hangers are provided. The document also includes a case study of noise control applied to an HVAC system, identifying common noise sources and effective control approaches like equipment location, sealing, isolation, attenuation, and ductwork design. Active noise control is discussed as a supplement to traditional passive methods.
This document discusses various methods for noise reduction from mechanical equipment. It describes using rubber mounts, vibration isolation, and insulation to reduce noise from pumps, generators, ducts, and other machinery. Specific guidelines are provided for vibration isolation of pumps based on horsepower and beam spans. Characteristics of duct systems that influence noise propagation are explained. Different isolation techniques are outlined for controlling noise within air conditioning ducts and from pumps and generators.
This document discusses noise pollution, including its definition, sources, measurement, effects on the environment and humans, monitoring devices, and methods for control and prevention. It defines noise pollution as unwanted sound that penetrates the environment from an external source. Major sources listed include street traffic, railroads, airplanes, and construction. Measurement units and health impacts are also summarized, along with legislative guidelines and strategies for noise control, including reducing noise at the source, blocking transmission paths, and using protective equipment.
This document discusses noise pollution, its sources, effects, and methods for control. It defines noise pollution and sound, and lists common sources like construction, traffic, and industry. Noise measurements are explained using dB levels and dosimeters. Health effects from noise pollution include hearing loss, stress, and sleep disruption. Control methods addressed include using quieter equipment, barriers, enclosures, scheduling work to minimize exposure, and protective equipment like earplugs. Studies have evaluated noise levels inside and outside hospitals in Egypt. References are provided.
Noise pollution refers to the production of unwanted, annoying or damaging sounds. Common sources include street traffic, construction, airplanes, and consumer products. The normal level of tolerance is 80dbA, with sounds above or below this level considered noise pollution. Exposure to excessive noise can damage hair cells in the ear and lead to hearing loss over time. Noise pollution also negatively impacts humans, vegetation, animals and property. Control methods include reducing noise at the source, blocking transmission paths, and using protective equipment. Legislation regulates noise limits for different zones.
NOISE REDUCTION FROM MECHANICAL EQUIPMENTS , RUBBER MOUNTS , VIBRATION ISOLATION GUIDELINES , CHARECTERISTICS OF DUCT SYSTEM , NOISE IN AC DUCTS , VIBRATION ISOLATION OF PUMPS AND GENERATORS
This document discusses noise pollution. It defines noise as unwanted sound and notes that noise originates from human activities like urbanization and transportation. Noise is measured in decibels. Measurement tools include sound level meters and dosimeters, which can assess workers' noise exposure over time. Methods to reduce noise include eliminating sources, attenuating pathways, and limiting exposure durations. Surveys identify noise sources and exposures. Control measures follow a hierarchy from elimination to substitution to engineering to administrative to personal protective equipment. Vegetation can help absorb sound.
Chapter 8 noise mitigation and measurementNoor Farahin
This document discusses noise pollution mitigation and measurement. It begins by explaining the goals of understanding noise pollution mitigation strategies to reduce noise at its source or protect receivers, as well as measuring noise pollution levels. It then provides details on various noise mitigation techniques including barriers, traffic control methods, and architectural acoustic designs. Noise measurement procedures and equipment like sound level meters and dosimeters are also outlined. Key steps include calibrating devices, taking measurements at specific distances and heights, and accounting for environmental conditions.
Chapter 8 noise mitigation and measurementNoor Farahin
This document discusses noise pollution mitigation and measurement. It explains that noise pollution mitigation aims to reduce noise pollution at its source, control noise pollution sources, and protect receivers from noise pollution. Methods include installing double-paned windows, using noise barriers like walls, and controlling traffic. Noise is measured using sound level meters and dosimeters which measure sound pressure levels and intensities. Proper use and calibration of this equipment allows for effective noise pollution measurement.
This document provides guidance on noise control methods for building exterior HVAC equipment. It notes that HVAC equipment can generate noise that propagates to nearby buildings, so early consultation with an acoustical consultant is recommended. Source controls like equipment selection and placement are most effective at reducing noise. Example control methods include noise barriers, acoustic louvers, duct silencers, and absorption materials. The document lists regulations for HVAC noise limits and example product vendors.
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1. NOISE & HEARING
(KAS 3501)
Year 3 (II) 2014/2015
Group 18
May 13th 2015
MUHAMMAD NUH B SULAIMAN U K 3 0 0 0 6
WAN HAFIZAH BT WAN ZAKARIA U K 3 0 0 5 8
LEE SOK YEEN U K 2 9 5 6 1
NABILA BT MD HANIF U K 3 0 1 0 4
NUR FARHANA BT MAT NOH U K 2 9 5 6 3
2. 1. INTRODUCTION
Noise is unwanted or offensive sounds that
unreasonably intrudes into our daily activities.
Classified as physical hazard.
May lead to permanent and irreversible damage to
hearing.
REGULATIONS
o Factories and Machinery (Noise Exposure)
Regulation1989
o Aim at protecting employees while they works
o Regulation 5 – Permissible Exposures Limit
o No employee shall be exposed to noise level exceed
continuous sound level of 90dB (A)
o No employee shall be exposed to noise level exceed
115dB (A) at any time
o No employee shall be exposed to impulsive noise exceed
a peak sound level of 140dB (A)
3. NOISE CONTROL - CONCEPT
AND BASIC PRINCIPLE
As in all hazard control, noise control efforts should
be approached according to the hierarchy of control
strategies, i.e. using the paradigm:
Noise from most equipment comprises mainly waste
energy.
The best way to reduce noise is to tackle the
problem at the source.
At the other end, reduction at receiver (i.e. affected
employee) is achieved by either removing the
employee from the sound field, limiting his working
time in the area.
4. 4. OVERALL NOISE CONTROL
PROCEDURE
o Appropriate control measures includes;
o Change in plant design and layout
o Substitution of a less hazardous work method
o Reduction of the hazard at its source
o Reduction of the hazard at its path of transmission.
Thus the recommended method of approach is
outlined below;
Plant planning (design and layout)
Substitution (equipment, process, material)
Engineering control
Control at source (modification of noise generator)
Control at path (modification of sound wave)
5. CONTROL BY PLANT
PLANNING
Successful planning for noise control involves:
Knowledge of the noise characteristics of each machine
and process;
Proposed location of each noise source, operator, and
maintenance man;
Selection of design criteria based on employee exposure
time.
It is important to consider the following:
The building's load-bearing structure
Powerful noise sources should be enclosed by structures
Rooms where there are sound sources and where
personnel are present continuously should be provided
with ceiling
Office areas should be separated from building elements
where vibrating equipment is installed by a joint of elastic
material.
6. CONTROL BY SUBSTITUTION
a) Use Quieter Equipment
The first step in providing quiet workplace equipment is to make a
strong effort to have equipment purchase specifications include noise
emission limits. When acquiring new equipment, its type and speed
should be selected on the basis of the applicable noise criteria.
b) Use Quieter Processes
In many cases, changing the process can be one way of getting to
grips with noise generation. This would in turn involve cooperation
between the employer, supplier, process designer and OSH
professional.
In most building and construction work, Hazardous local noise levels
are generated both by the impact on the pile and from the explosion,
and annoyance may be caused at distances of up to a few miles.
c) Use Quieter Material
Materials from which buildings, machinery, piping and containers are
constructed have a vital relation to noise control. Some materials have
high internal damping and are called 'dead' materials, while others
called 'live' materials have little internal damping and cause a ringing
sound when struck.
7.
8. ENGINEERING NOISE CONTROL
Existing Equipment
a) Once generated, noise can transmit through;
i. Direct sound field
ii. Reverberant sound field
iii. Structure-borne path
b) Reduce amount of work hour in the sound field.
c) Proper maintenance of equipment.
9. ENGINEERING NOISE CONTROL
Systematic Approach
o Control noise from existing equipment by applying
engineering principal.
Generated
noise
Radiated
noise
Control at
source
Directly
transmitted
noise
Reverberant
noise
Structure-
borne noise
Control at
path
Control at
receiver
10. • Reduction or elimination of the impact and generation of noise
• Modification of equipment which reduce the metal-to-metal
contact (eg: blade,gear etc)
Generated Noise
• Move the machine to new place far from the exposed
employees
• Apply vibration isolation to machine housing
Radiated Noise
CONTROLAT
SOURCE
CONTROLAT
PATH
• Use sound absorptive material
• Construct and acoustical barrier to shield, deflect or absorb
noise energy
Directly Transmitted Noise
• Use sound absorptive material (eg: fiberglass, acoustic tiles on
wall, ceiling etc)
• Reduce reflection by move the machine far from corner or walls
Reverberant Noise
• Use duct lines with sound-absorptive material
• Use wrapping on pipe to increase their sound insulation
Structure-borne Noise
11. Use enclosure or control room to house the
employee.
Reduce the amount of time the employee is
allowed to work in a high noise area.
Provide HPE to the employee.
CONTROLAT
RECEIVER
13. REDUCE IMPACT NOISE
Mechanical and material handling devices-
produce noise from impact
Reducing the dropping height of goods collected in
boxes or bins
Using soft rubber or plastic to receive and absorb
hard impacts
Increasing the rigidity of containers receiving
impact goods and adding damping material —
especially to large surfaces.
Regulating the speed or cycle time of conveyors to
prevent collisions and excessive noise.
14. REDUCE OR ELIMINATE
AERODYNAMICALLY GENERATED
NOISE
• Change the character of the noise
• Reduce the surface area of the source
• Change the source dimensions such that
noise is cancelled out at the edges
• Reduce or remove interrupted-wind tonal
noise
• Reduce turbulence in fluids
• Reduce fan noise
• Use silencers
• Reduce Vibration
15. CHANGE THE CHARACTER OF
THE NOISE
Replacing a noise source with one of higher
noise frequency may reduce the sound
level at typical property-line distances
16. REDUCE THE SURFACE AREA
OF THE SOURCE
When large surfaces vibrate they will
produce high sound levels. Consider
replacing solid plates, wherever possible,
with expanded metal, wire mesh or
Perforated
17. CHANGE THE SOURCE DIMENSIONS SUCH
THAT NOISE IS CANCELLED OUT AT
THE EDGES
At the edges of large vibrating plates, the
compression and rarefaction sound waves
tend to cancel each other out using long
narrow surfaces instead of square or
approximately square surfaces
18. REDUCE OR REMOVE
INTERRUPTED-WIND TONAL NOISE
When tonal noise is produced by machinery due to this
effect, it maybe possible to eliminate the wind (i.e. the air
flow) by filling out any hollow space, thus removing the
noise created by it.
19. REDUCE TURBULENCE IN
FLUIDS
• Fluid noise is due to turbulence. The more turbulent
the flow, the greater would be the noise.
• Vapour bubbles can be created by abrupt changes in
the flow of fluids. Providing
gradual transition in cross-sectional area reduces the
likelihood of these bubbles
forming
20. Turbulence at the walls of ducts or pipes is always
present. To reduce noise;
Interior walls should be smooth, free of protrusions at joints,
and sharp bends at 'tees' (T junctions) and 'wyes' (Y
junctions) should be avoided.
Turning vanes can be placed inside ductwork when
construction methods utilise sharp bends.
Straightening vanes can be used to smoothen the flow
downstream of any change in direction, diameter, or
branching
21. USE SILENCERS
Absorptive silencer:
Simplest form: lined duct
considered for cooling and exhaust air
whenever sources are to be enclosed
Reactive silencer:
simplest form: single expansion chamber
the expansion and contraction in pressure
cause reflection of sound waves.
The reflected wave added to the incoming
sound wave results in destructive
interference, leading to noise reduction.
22. REDUCE VIBRATION
• Shifting instrument panel to wall
• Putting damping on flexible panel
• Obtaining maximum isolation by stiffening the floor
structure; or mounting the machine on ground-
founded pillars
• Placing heavy vibrating equipment on inertial block
with vibration isolators and dampers.
• Flexible connectors for preventing vibration
transmission to building structure.
• Isolation of pipe work on refrigeration plant by use
of flexible couplings
• Shifting small service machinery onto isolators on a
solid floor
• Reducing resonance in a circular saw blade
24. DEFINING SOUND FIELDS
Near Field The region close to a sound source usually defined
as 1/4 of the longest wavelength of the source.
Near field references can pertain to both indoor and
outdoor environments.
Far Field Sound field beyond the near field limits described
above where the sound pressure level (SPL) drops
off at the theoretical rated of 6 dB for every
doubling of distance from the source.
Direct Field To describe far field conditions that follow the
Inverse Square Law SPL loss rate of 6 dB for every
doubling of the distance.
Diffuse Field There are so many reflections contributing to the
total sound field that sound levels measured
virtually anywhere in the sound field are the same.
Diffuse fields usually pertain to indoor environments
Reverberant
Field
Essentially the same as the diffuse field.
For indoor sound field discussions it is used to
contrast direct fields.
25. NOISE REDUCTION OBTAINED
FROM USE OF NOISE BARRIER
If a sound source is in a room with a large amount
of absorption present, blocking the direct path with
a partial barrier may provide adequate noise control.
Indeed, this technique is more often used outdoors,
since even a modest amount of reverberation will
destroy the effectiveness of a shield.
26. OSHA DECIBEL LEVELS – HEARING
PROTECTION
Employee exposure to excessive noise depends
several factors including;
The loudness of the noise as measured in
decibels (dB)
The duration of each employee’s exposure to the
noise
Whether employees move between work areas
with different noise levels (decibel levels)
Whether noise is generated from one or multiple
sources
Generally, the louder the noise, the shorter the
exposure time before hearing protection is
required.
28. DECIBEL LEVELS OF
ENVIRONMENTAL SOUNDS
Source--Dangerous
Level dBA SPL
Produces Pain
(120-140dB)
Jet Aircraft During
Takeoff (at 20
meters) (130dB)
Snowmobile
Tractor Without
Cab (120dB)
Rock Concert
(110dB)
Die Forging
Hammer
Gas Weed-
Whacker
Chain Saw
Pneumatic Drill
(100-105dB)
Home Lawn
Mowers (95 to
100dB)
Semi-trailers (at
20 meters) (90dB)
Source--dBA SPL
Discomfort Level
Above (80dB)
Heavy Traffic
(80dB)
Automobile (at 20
meters) (70dB)
Vacuum Cleaner
(65dB)
Conversational
Speech (at 1
meter) (60dB)
Quiet Business
Office (50dB)
Residential Area
at Night (40dB)
Whisper, Rustle of
Leaves (20dB)
Rustle of Leaves
(10dB)
Threshold of
Audibility (0dB)
29. TYPES OF HEARING
PROTECTION
Some types of hearing protection include:
Single-use earplugs are made of waxed cotton, foam, silicone
rubber or fiberglass wool. They are self-forming and, when
properly inserted, they work as well as most molded earplugs.
Pre-formed or molded earplugs must be individually fitted by
professional and can be disposable or reusable. Reusable plugs
should be cleaned after each use.
Earmuffs require a perfect seal around the ear. Glasses, facial
hair, long hair or facial movements such as chewing may reduce
the protective value of earmuffs.
30. REFERENCES
Health, N. I. (2014, August 08). Center for Disease Control and
Prevention. Retrieved from USA.gov:
http://www.cdc.gov/niosh/topics/noisecontrol/
Industrial Noise Control Manual, Revised Edition, National
Institute of Occupational Safety and Health (USA)
Editor's Notes
The table, below, shows the permissible noise exposures that require hearing protection for employees exposed to occupational noise at specific decibel levels for specific time periods.