Use of adjustable lab stool with backrest to provide support and promote food postureElevate chair according to working height to avoid working with arm elevated
Use an electronic or a latch-mode pipette to replace manual plunger-operated pipette as it reduce the need for excessive thumb force and repetitionUse of multi-finger control help to distribute the force among several fingers rather than continuously using the same finger
Use of padded wrist rest for keyboard and input devices to prevent the user wrist from coming into contact with the work surface when the arms are at rest
Ensure mini-breaks in between for every 20 to 30 minutes of usage of computer. Mild hand exercise or stretches could be done during the short breaks
Ensure that head and torso are in-line with head slightly bent forward, facing towards the front, and balancedEnsure that elbows are close to body and bent between 90 and 110 degrees
WORKPLACE SAFETY AND HEALTH 1 Ergonomics
GROUP MEMBERS Bak Fong Ning Eunice Chua Lam Man Pan Anna Tan Yu Jie Tong Ji Feng Xia Dong
SCOPE (PART 1) What Reason for Flowchart onDefinition:What Ergonomics using ergonomicsis Ergonomics? does? Ergonomics? study Background Introduction ofWhat regulator Symptoms of information of ergonomics says? poor ergonomics ergonomics hazards hazards Summary list ofRisk factors and ergonomic measurement hazards
SCOPE (PART 2) How to improve What you can doBudgets for the How to pick your work to improve Indoor control items perfect chair? ergonomically? Air Quality? Designing How to adjust the What are the productive seating classroom and Does ergonomics practical in classroom and laboratory to fit work? solutions? laboratory you? What is the Referencesdesign furniture Conclusion for change?
WHAT IS ERGONOMICS? The branch of science that is concerned with the achievement of optimal relationships between workers and their work environment Ergonomics Worker Work environment
WHAT IS ERGONOMICS? Deals with the assessment of the human’s capabilities and limitations Work and environmental stress Static and dynamic forces on the human body structure Vigilance Fatigue Design simulation and design of workstation and tools
WHAT IS ERGONOMICS? A multidisciplinary science which draw heavily from other fields of study like: Mathematics Biological science Psychological science Physics
WHAT DOES ERGONOMICS DO? Goal: To adapt work to individuals rather than individuals to work By developing knowledge that results in efficient adaptation of work methods to the individual physiological and psychological characteristics
WHAT ARE THE REASONS FORERGONOMICS? Achieve an optimal relationship between people and their work environment. Reducing occupational injury and illness reduction, Containing workers compensation costs, Improving productivity of the workers, Improving work quality, Reducing absenteeism Complying with the government regulations.
BACKGROUND INFORMATION OF ERGONOMICS HAZARDS Occur when type of work, body position and working conditions put strain on one’s body Hardest to spot because strains on a person’s body or harm from these hazards not always immediately noticed Short-term exposure result in "sore muscles" the next day or in days following exposure Long term exposure result in serious long-term injuries
INTRODUCTION OF ERGONOMICHAZARD Workplace conditions that pose risk of injury to the musculoskeletal system of worker Includes repetitive and forceful movements, vibration, temperature extremes, and awkward postures that arise from improper work methods and improperly designed workstations, tools, and equipment
Examples of Ergonomic hazards : Poor lighting Improperly adjusted workstations and chairs Frequent lifting Poor posture Awkward movements, especially if they are repetitive Repeating the same movements over and over Having to use too much force, especially if you have to do it frequently
SYMPTOMS OF POORERGONOMICS Cumulative Trauma Disorders (CTDs) are a class of musculoskeletal disorders involving damage to the nerves of the hands, wrists, elbows, shoulders, neck, and back. The more frequently occurring occupationally induced disorders in this class include carpal tunnel syndrome (CTS). CTDs are caused when workers are required to perform keyboard- intensive tasks without breaks or alternative work.
WHAT REGULATOR SAYS? Occupational Safety and Health Administration (OSHA) of the federal government lists ergonomics as a key factor in preventing musculoskeletal injuries in the workspace. OSHA expresses concern over poor design of furniture that does fit the task, and ineffective safety devices: anything that might precipitate an injury. Stress through prolonged sitting can be resolved to a great extent with an increased awareness of correct posture. Three basic sitting positions can promote a healthy posture: the torso may be positioned slightly forward, upright, or slightly reclining and always with both feet resting comfortably on the floor or on a footrest
ERGONOMIC ANALYTICAL TOOLS Provide job prioritization for intervention, quantification of activities associated with increased risk of injury, or recommendation for a load weight limit for lifting Used by examiner to determine which analytical tool is best for evaluation of the identified risks based on the understanding of the tool’s application, strengths and weaknesses
1. Rapid Upper Limb Assessment (RULA) Assesses the risk of cumulative trauma, disorder through posture, force, and muscle-use analysis2. Ovako Working Posture Analysis System (OWAS) Provides intervention, prioritization based on posture and loads3. Repetitive Motion Evaluation Analyses posture, repetition, and discomfort to reveal the performance of high risk motions
4. Observation Analysis of the Hand and Wrist Quantifies hand exertions associated with risk factors of pinch grip, high force, wrist flexion/extension/ulnar deviation, power tool exertion, and use of hand to strike object5. Utah Back Compressive Force Model Evaluates the risk of low back injury for a one-time lifting task based on lumbar disc compression6. Utah Shoulder Moment Model Evaluates the risk of shoulder injury for a onetime lifting task comparing task moment to an individuals capacity
7. NIOSH Work Practices Guide (1981) Evaluates the risk of a lifting task based on NIOSH parameters8. Revised NIOSH Lifting Equation (1994) Evaluates the risk of a lifting task based on expanded NIOSH parameters9. Liberty Mutual Tables Based on psychophysical experimentation, determines the maximum acceptable weight for a lifting/lowering task, push/pulling task, and carrying task given selected job characteristics. Tables are accessible from the Lifting/Manual Material Handling Job Review and Analysis Options
10. Amsterdam Masters in Medical Anthropology (AAMA) Metabolic Model Evaluates the risk of physical exertion strain for a task11. Anthropometry Analysis Determines proper workplace dimensions for various body sizes12. Detailed Checklist For Computer Video Display Terminals (VDT) Workstation Risk Analysis Presents the recommended characteristics of a VDT workstation
POTENTIAL ERGONOMICS HAZARD(BLK 34-06-02) Improper design of computer workstation Excessive overhead lighting Improper design of facilities (tables and chairs) Lifting and moving of tables or chairs Long period of time standing Long period of time sitting Continuous writing with hand or typing on a laptop/computer Tripping of electric cord Unclean air conditioner and ventilators
POSSIBLE CONTROL MEASURES Engineering control Administrative control
ENGINEERING CONTROL Improper design of computer workstation Use of foot rest Position the chair and desk such that the knee and forearms are 90° angles, with wrist straight and feet flat on the floor or foot rest Position the computer such that the top of the screen is at or just below the eye level, and the viewing distance is a safe distance away from the user eyes Excessive overhead lighting Use of adjustable tasks lights ambient lighting Use of anti-glare whiteboard
Improper design of facilities Use of flexi-chair (changing seat inclination) or rocking mechanisms (swivel chair with height adjustment) Use of height adjustable working table or inclined top Long period of time sitting Use of adjustable stool with a backrest Adjust the chair height such that the feet rest comfortably on the floor or foot rest
Long period of time standing Use of anti-fatigue mat Continuous writing with hand Use of better grip pen Tripping of electric cords Use of cable protector or floor cord cover Unclean air conditioner and ventilators Install new unit ventilators and air handlers or regular cleaning and maintenance of ventilation system
ADMINISTRATIVE CONTROL Lifting and moving of tables and chairs Request for help when lifting or moving heavy objects Long period of sitting and standing, and continuous writing with hand Taking short breaks in between the work schedule
POTENTIAL ERGONOMICS HAZARD (BLK 35 LABORATORY) Long period of time sitting Long period of time standing Repetitive pipetting Improper design of facilities (fume hoods, biosafety cabinet, laboratory workbenches) Improper design of computer workstation Moving of heavy objects Stress Compact work surface Excessive overhead lightings Personal laboratory equipment
POSSIBLE CONTROL MEASURES Engineering control Administrative control Personal protection equipment (PPE) Work practice controls
ENGINEERING CONTROL Long period of time sitting Use of adjustable lab stool with backrest Adjust chair height such that the feet can rest comfortably on the floor or footrest Tilt the chair seat forward to prevent leaning Keep frequently used items within arm reach Long period of time standing Use of anti-fatigue mat Place one foot on a small stool and alternate to reduce pressure to the back
Repetitively pipetting Elevate chair according to working height Use of light-weight pipette or electronic or latch-mode pipette Use of multi-finger control Use thin-walled pipette tips Work the pipette with arm close to body to reduce strain on shoulder
Improper design of facilities (fume hoods, biosafety cabinets and laboratory workbenches) Position materials in fume hood as close as possible to avoid extended reaching Apply padding for arm and wrist to rest Lights in fume hood must be working properly. Replace bulbs when necessary Use ergonomically designed chairs with proper back support, seat angle and height adjustability Use foot rest Removal of drawers under workbenches Use turntable to store equipment to avoid extend reaching and twisting Proper design of stool or benches such that it is not too high for most users to use
Improper design of computer workstation Provide fully adjustable seating Place monitor such that the top of the screen is near or at eye level to allow the eye to naturally gravitate towards the center of the screen Provide foot rest for user to change leg position through the day Regular maintenance of workstation, chairs and equipment Use of padded wrist rest Ensure that the user shoulder muscles or tendon does not work to reach forward or out to side, otherwise, further alteration of workstation is needed Ensure that the keyboard and input device (mouse) is at the same level and in front of the computer, and the height of the keyboard and input device should allow the user to position their forearms and hands parallel to the floor Adjust monitor contrast and brightness for maximum personal comfort of user
Moving of heavy objects Use handling equipment (lifts or hoist) to avoid manual handling Push instead of pull Use sliding motion or lateral transfers instead of lifting the load Decrease the weight of load and allow more frequent trips of moving lighter load Pivot the feet instead of twisting the back when lifting the load Compact work surface Ensure work surface is large enough to allow free leg movement Ensure the height of work surface allow the forearms to be parallel to the floor when working, avoid having shoulder elevated Excessive overhead lightings Use a task tamp when needed
ADMINISTRATIVE CONTROL Long period of time sitting and standing, repetitively pipetting, improper design of facilities (fume hood, biosafety cabinet and laboratory workbench), improper design of computer workstation, and moving of heavy objects Take short breaks in between the work schedule Moving of heavy objects Optimize work shift scheduling to minimize extended work load Ask for more people to assist moving load
PERSONAL PROTECTION EQUIPMENT(PPE) Personal laboratory equipment Safety goggles Gloves
WORK PRACTICE CONTROL Repetitively pipetting Introduce worker education and awareness sessions Improper design of computer workstation Early reporting of signs and symptoms of ergonomic concerns Training for user on ergonomics hazard and control strategies
CONTROL ITEMS FORLABORATORY Deluxe goggles (S$15.12) Crag work boot (S$185.76)
Edge protector – 0.762m(S$23.24) Adjustable work benches – 0.762m x 1.524m (S$1249.58)
Vinyl Cover seat with adjustableheight (adjustable from 0.508mto 0.686m in height)(S$577.19) Safety fatigue mat – 0.102m x 1.524m (S$738.08)
Wireless ergonomic multimedia keyboard and mouse (S$64.68)
HOW TO IMPROVE WORKERGONOMICALLY Know the current working condition of the workplace Get compared with the legislation or COP Identify the potential factors which may cause injury to the workers and list them out Give suggestions to make changes regarding the unsuitable factors When all details of every area in the workplace is considered, examined and actions have been done, work is improved ergonomically Having proper chair-height adjustment can help keep the wrists in a flat position, and the control of both backrest angle and seat-pan forward-tilt further aids in relaxation and the reduction of muscular tension while helping proper hand arm orientation.
WHAT YOU CAN DO TO IMPROVEINDOOR AIR QUALITY1. Apply good ventilation system2. Choose suitable ventilation system. (LEV system for workplace with gaseous pollutants produced by fixed origins with high concentration)3. Monitor the air quality constantly.4. Clean the duct or other ventilation system components regularly.
HOW TO PICK YOUR PERFECT CHAIR? Chair is the most important piece of furniture. Without a comfortable, supportive chair, you would not be an efficient worker. Sitting for prolonged periods of time can cause poor posture and reduce circulation of the blood, which often results in severe back pain. An ergonomic chair should provide your back, especially your lumbar region (lower back) with support. A quality chair should have an adjustable lumbar support Users should be able to move the back rest forward, reducing the seat pan depth, to ensure that people with shorter legs receive proper back support while still being able to rest their feet on the ground or foot rest. They should be able to adjust the back support forward or backward to accommodate the curvatures of the spine and properly support their body weight.
HOW TO PICK YOUR PERFECT CHAIR? Important that the seat height be adjustable. A footrest also can help improve comfort for a shorter user who is working at a fixed-height work surface. A good ergonomic chair also allows adjustment of both the back-tilt angle and seat pan depth while seated. Seat pan (the surface on which you actually sit) should have a soft front edge, ensuring that there are no pressure points to hurt the underside of the thighs. Perfect chair should allow users to sit upright with arms hanging straight down from the shoulders and with the elbows bent Allow users to sit flat on the chair with knees bent and feet flat on the floor or foot rest and it should support the user’s back in an upright position.
HOW TO ADJUST THE CLASSROOMAND LABORATORY TO FIT YOU?a) Adjust your chair Arm position1. Raise your forearms to be parallel with the floor while maintaining a 90 degrees elbow bend.2. Adjust your chair to achieve this position. Keep the wrist straight as an extension of your forearms. Foot support1. Move your feet forward until your knees are at a 90 to 110 degrees angle. Your feet should rest firmly on the floor with 3-6 inches (7.62cm-15.24cm) of leg room between your lap and desk.2. If you do not have a footrest and cannot adjust your chair height or your feet don not touch the floor, use a phone book or a 3-ring binder as a quick and easy footrest.
HOW TO ADJUST THE CLASSROOMAND LABORATORY TO FIT YOU? Backrest1. Sit in your chair with the backrest snugly against your lower back.2. You should be able to place your hand easily between the back of your knees and the edge of the seat pan.3. If you cannot do this, you may be able to achieve improved support by placing a pillow between your seat and lower back to restore natural curvature.
DESIGNING THE PRODUCTIVESEATING IN CLASSROOM ANDLABORATORY Seat Pan Height Ideally, adjustable 40cm- 53cm from the floor to the top of the seat pan. Seat Pan Depth Maximum seat pan depth 38cm-44cm Also provide a “waterfall” forward-sloping front edge on the seat pan Seat Pan Width Minimum seat pan width 46cm
Seat Pan Slope Adjustable 0 to -10 degrees Seat Back Tilt Minimum range 0 to 15 degrees Seat Back Height Minimum seat back height 36cm
DESIGNING THE PRODUCTIVESEATING IN CLASSROOM ANDLABORATORY Seat Back Width Minimum seat back width 30cm Armrest Height Between 15cm – 17cm above the centre height of the seat pan Armrest Length Minimum armrest length 15cm Armrest Width Minimum armrest width 5cm Armrest separation Between 46cm and 56cm.
WHAT ARE THE PRACTICALSOLUTIONS? Maintaining ergonomic seating in workplace Check whether workstation is set up well. Keyboard, monitor, and person’s posture should be on straight line to avoid seating discomforts To not look up at the screen. Adjust chair to look down at screen instead Desktop to be at convenient height with enough space for computer and papers Chair to give good support to user’s back with height-adjusting options Keyboard and mouse mat to have good-wrist rest
Ergonomic seating- elbow angle Ensure that head and torso are in-line with head slightly bent forward, facing towards the front, and balanced Ensure that elbows are close to body and bent between 90 and 110 degrees
ERGONOMIC SEATING- FOOTREST Feet supported by a footrest or relaxing on floor Ensure back supported fully while leaning back or sitting in vertical position Seat well padded to support hips and thighs Ensure that knees and hips in almost same height with feet slightly forward
WHAT IS THE DESIGN FURNITUREFOR CHANGE?Seat design Basic size and shape of any seat determined largely by anthropometric considerations: Seat height should not be greater than popliteal height of a small user (5th percentile) Seat depth (from front edge to the backrest) should not be greater than the buttock-popliteal length of a small user (5th percentile) Seat breadth between arm rests should give clearance for large user (95th percentile hip breadth or elbow-elbow breadth plus leeway). Seat breadth little less than hip breadth for seats without arm rests*popliteal: back part of the leg behind the knee joint
Backrest designed to support weight of user’s trunk. Backrest extend upwards, at least into shoulder region of user Backrest angle determined by purpose of the seat. Angle of 100° to 110° from horizontal generally suitable for working chairs and 110° to 120° for rest chairs. Seat surface should be horizontal in a working chair or tilted backwards (by an angle of 5° to 10°) in a rest chair
Shod feet flat on floor Clearance between thigh and underside of table for freedom of movement Clearance between back of legs and front edge of seat
Chairs Should be stable throughout full range of postures that user adopts Five-point base of support suitable for rotatable chairs Seat surface should be substantially flat No part more than 25mm higher than any other Upper surface of front edge resilient or rounded Seat to be padded or upholstered Upholstery materials permeable to air and water vapour Backrest of office chair should provide: Adequate support for office worker in lumbar region Space for bottom and movements of shoulder blades Permit arm and elbow movement
Tables length of desktop, table or worktop should be some multiple of 100mm and width, some multiple of 50mmPreferred sizes are as follows: Length of the desktop Width of the desktop 1200 600 1200 800 1600 800
Working posture of person sitting at writing desk determined by: the height of the seat the height of the desk lesser degrees of adjustment adequate in real practice
CONCLUSION Deals with interaction of technological and work situations with human being Basic human sciences involved are anatomy, physiology and psychology Basic anatomy Basic anatomy is based on improving physical fit between people and things they use Difficult to achieve as need to consider range in human body sizes across population
Physiology Work physiology addresses energy requirements of the body and sets standards for acceptable physical work rate and workload, and for nutrition requirements. Environmental physiology analyses impact of physical working conditions - thermal, noise and vibration, and lighting - and sets optimum requirements accordingly Psychology Concerned with human information processing and decision-making capabilities Increasing automation, while dispensing with human involvement in routine operations, increases mental demands in terms of monitoring, supervision and maintenance
Books Human Factors in Design, contributors Jim Sage, Alan Goodier Ergonomics: How to design for ease and efficiency, By K.H.E Kroemer A resource guide for ergonomics Guidelines/ Code of Practice/legislation Occupational Safety and Health Administration (OSHA) Rapid Upper Limb Assessment (RULA) Anthropometry Analysis