https://pms.mypolycc.edu.my/ Aniza Md Latiff Suyani Arifin Azlinda Mohamad 2023 ERGONOMICS Introduction to Ergonomics in Product Design
ERGONOMICS INTRODUCTION TO ERGONOMICS IN PRODUCT DESIGN
Aniza Md Latiff Azlinda Mohamad Suyani Arifin All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, electronic, mechanical, photocopying, recording or otherwise, without the prior permission of the Publisher. © Politeknik Muadzam Shah Publisher Politeknik Muadzam Shah, Lebuhraya Tun Razak, 26700 Muadzam Shah, Pahang. 2023
i ABSTRACT The first edition of Ergonomics is written for polytechnic students as a reference in their course study. This e-book was written by the lecturers from Product Design Program. The contents in this e-book are relevant to the Ergonomics taken by semester 4 students in the Department of Mechanical Engineering, Politeknik Muadzam Shah. It’s also can be used as a reference book for all undergraduate students in mechanical engineering. This book consists of 5 subtopics as the content of the Introduction to Ergonomics. Hopefully, it can be used as a main reference for polytechnic students, especially in Diploma Mechanical Engineering (Product Design).
ii ACKNOWLEDGEMENT First and foremost, thanks to Allah S.W.T. for the guidance and mercy. The completion of this Ergonomics ebook could not have been possible without the support and encouragement from colleagues. Thank you to colleagues for developing the ebook and for people willing to help with their abilities. It has been a great honor and privilege to undergo this process of creating an ebook that helps to gain as an educator to share knowledge.
iii Table of Contents ABSTARK.................................................................................................................................................. i ACKNOWLEDGEMENT ........................................................................................................................... ii 1.0 Define the development of ergonomics ............................................................................... 1 1.1 Industries Involve in Ergonomics ....................................................................................... 4 1.2 Benefits of Ergonomics ........................................................................................................ 4 2.0 Classify the domains of Ergonomics ...................................................................................... 5 2.1 Determine the purposes of ergonomics in Design ......................................................... 5 2.2 Construct a simple work system on how people interact with machines ................. 6 3.0 Human Machine System ......................................................................................................... 6 4.0 Explain the ergonomics risk factors....................................................................................... 9 4.1 Force...................................................................................................................................... 10 4.2 Vibration............................................................................................................................... 11 4.3 Repetition ............................................................................................................................ 13 4.4 Contact stress ...................................................................................................................... 15 4.5 Awkward posture................................................................................................................ 17 4.6 Extreme temperature......................................................................................................... 18 4.7 Static posture....................................................................................................................... 20 5.0 Ergonomics Controls .............................................................................................................. 22 5.1 Engineering Control ............................................................................................................ 22 5.2 Administrative/ work practice Control .......................................................................... 25 5.3 Work practice control ........................................................................................................ 27 5.4 Personal Protective Equipment (PPE) ............................................................................ 30 5.5 Hierarchy of Control .......................................................................................................... 32 6.0 Various Ergonomics in Design .................................................................................................. 33
1 1.0 Define the development of ergonomics Figure 1.1: Ergonomics In 1949: “Ergonomics” was defined by Murrell, after consultation with Greek and Latin Scholars, as “the study of the relationship between man and his working environment”. In several countries, the term human factors is also used. Figure 1.1 showed a graphic for the definition of ergonomics. Ergonomicsis the study of the relationship between the employee and the workplace. It is a developing body of knowledge whose goal is to provide and maintain a healthy “userfriendly” environment. Properly applied, ergonomic principles support each person's desire to find a zone of individual comfort. Ergonomics is an interdisciplinary field that studies how individuals interrelate with the working environment, to create tasks, jobs, and products that are safe, efficient, and comfortable (Jishin Jayan Thrippunath, 2023). Ergonomics is about ’fit’: the fit between people, the things they do, the objects they use, and the environments they work, travel, and play in. If a good fit is achieved, the stresses on people are reduced. They are more comfortable, they can do things more quickly and easily, and they make fewer mistakes."
2 "Human Factors refer to environmental, organizational and job factors, and human and individual characteristics, which influence behavior at work in a way which can affect health and safety“. Figure 1.2: Human Factors The definition of human factors includes 3 interrelated aspects that must be considered: the job, the individual, and the organisation. Figure 1.2 showed the graphic of human factors.
3 Ergonomics (human factors) is the scientific discipline concerned with the understanding of interactions among humans and work systems. Ergonomists contribute to the design and evaluation of tasks, products, environments, and systems in order to make them compatible with the needs, abilities, and limitations of humans. In several countries, independent certifying bodies can certify professional ergonomists(Jan Dul, 2008). In Europe, for example, the Center for Registration of European Ergonomists (CREE) decides on candidates for registration as European Ergonomists, the same as the USA. There are other experts besides professional ergonomists who make use of ergonomic knowledge, method, and techniques. These would include, for example, industrial engineers, industrial designers, company doctors, company nurses, physiotherapists, industrial hygienists, and industrial psychologists. Ergonomists contribute to the design and evaluation of tasks, jobs, products, environments, and systems in order to make them compatible with the needs, abilities, and limitations of people. The job: including areas such as the nature of the task, workload, the working environment, the design of displays and controls, and the role of procedures. Tasks should be designed in accordance with ergonomic principles to take account of both human limitations and strengths. This includes matching the job to the physical and the mental strengths and limitations of people. The individual: including his/her competence, skills, personality, attitude, and risk perception. Individual characteristics influence behaviour in complex ways. Some characteristics such as personality are fixed; others such as skills and attitudes may be changed or enhanced. The organisation: including work patterns, the culture of the workplace, resources, communications, leadership and so on. Such factors are often overlooked during the design of jobs but have a significant influence on individual and group behaviour.
4 1.1 Industries Involve in Ergonomics Ergonomics is important in a wide range of fields, including manufacturing, construction, healthcare, and office work. Implementing good ergonomic practices in these fields can lower the risk of musculoskeletal disorders (MSD) and other health issues, enhance productivity, and promote job satisfaction (Jishin Jayan Thrippunath, 2023). Most fields are involved with ergonomics. Figure 1.3: The fields involved with ergonomic 1.2 Benefits of Ergonomics Figure 1.4: Benefits of Ergonomics Aerospace Automotive Chemical Computer Consumer products Construction Defense Healthcare Manufacturing Mining Nuclear Petroleum Telecommunications Textile Productivity Efficiency Morale Injury Risk Mistakes/ Reworks Lost Work Days Turnover INCREASE DECREASE
5 Ergonomics involves many areas in the world. It is because ergonomics give more benefit. Figure 1.4 showed productivity, efficiency, and morale will increase with ergonomics. Implications ergonomics effect to decrease injury risk, mistakes or rework, lost work day, and turnover. 2.0 Classify the domains of ergonomics Domains of specialization within the discipline of ergonomics: Physical ergonomics – is concerned with human anatomical, anthropometric, physiological, and biomechanical characteristics as they relate to physical activities; Example: working postures, materials handling, repetitive movement, WMSDs, workplace layout, safety & health. Cognitive ergonomics – is concerned with mental processes, such as perception, memory, reasoning, and motor response, as they affect interactions among humans and other elements of a system. Examples: mental workload, decision-making, human-computer interaction, work stress, etc. Organizational ergonomics – is concerned with the optimization of sociotechnical systems, including organizational structures, policies, and processes. Examples: design of work process, design of working times, macro ergonomics, quality management, etc. 2.1 Determine the purposes of ergonomics in design The purposes of ergonomics are to: i. Enhance human (worker, user) performance; ii. Increase human safety and health; iii. Improve human satisfaction. Ergonomics aims to improve the workspace environment in order to prevent injury or harm to the employee. It brings human abilities and limitations into the design of the workspace as it accommodates, for example, their size, vision, hearing, and even attitudes.
6 2.2 Construct a simple work system on how people interact with machines The practice of ergonomics requires knowledge about i. human anatomy, ii. physiology, iii. psychology Particular emphasis is placed on the design of the human-machine interface (work system) to ensure increased safety and usability of equipment and the removal of harmful stressors. All work systems consist of a human component and a machine component embedded in a local environment. Figure 2.1: Simple Workstation (Gokhan Usma, 2022) 3.0 Human-Machine System Human–machine system is a system in which the functions of a human operator (or a group of operators) and a machine are integrated. Figure 2.1 showed the simple workstation. The simple workstation has 2 types simple ergosystems and complex ergosystems. Complex systems that comprise both humans and machines. The 3 major aspects of human-machine systems, in roughly historical order, are: i. systems in which the human acts as a manual controller, ii. systems in which the human acts as a supervisory controller, iii. human interaction with artificial intelligence systems
7 Figure 3.1: simple Work system (N. Stanton, 1999) A simple work system. People interact with machines to turn inputs into outputs. System capacity refers to the amount of input that can be processed over time. Productivity refers to the ratio of outputs to inputs. Efficient systems minimize by-products of all kinds (E =local environment, M = machine, H = human operator). Figure 3.1 showed a simple work system. Figure 3.2 show the relationship between human and machine. Figure 3.2: Relationship between human and machine (Tanya Mohan Tukade, 2018)
8 In a simple work system, it consists of: i. Human (H) ii. Machine (M) iii. Environment (E) Six directional interactions are possible: 1. H > M 4. M > E 2. H > E 5. E > H 3. M > H 6. E > M Example of a simple work system: A carpenter (H) uses a handsaw (M) to produce a boat using a tree (E). Relationship between H, M, E: 1. H > M (the carpenter is safe while sawing) 2. H > E (the fertile soil is eroded when the carpenter cuts the tree) 3. M > H (the fit between the hand and the handsaw) 4. M > E (the handsaw makes it possible for the carpenter to cut trees) 5. E > H (the eroded environment may no longer sustain carpenter life) 6. E > M (the handsaw becomes blunt through continued use to cut other trees) The complexity of a working system may be increased by introducing further human and/or machine components or by enlarging the local environment. Each component of a working system may interact either directly or indirectly with the others. For example, the machine component may change the state of the environment (by emitting noise or heat, for example) and this may affect the human component.
9 4.0 Explain the ergonomics risk factors Ergonomics risk factors are the aspect of a job or task that impose biomechanical stress on the worker. They can be classified into several types: Figure 4.1: Ergonomics risk factor
10 4.1 Force It refers to the amount of physical effort required to complete the task. The amount of force depends on the type of grip, the weight of an object, body posture, the type of activity, and the duration of the task. Excessive force gives impacts on muscles, tendons, ligaments, and joints. This condition leads to fatigue, irritation, inflammation, strains, and tears in muscles and other tissues. Examples of activities: lifting heavy objects, pushing and pulling heavy trolley. Figure 4.2 show example work involves force. Figure 4.2: Example Work involves force (OshAcademy, 2023) Heavy lifting involves exerting excessive force while handling objects that exceed an individual's physical capabilities or are improperly lifted. This can lead to various musculoskeletal injuries and strains. For instance, imagine a warehouse worker regularly lifting and moving heavy boxes without using proper lifting techniques or assistance. The excessive force required to lift these heavy objects can put a significant strain on the worker's back, shoulders, and other muscles, potentially leading to injuries such as sprains, strains, or herniated discs.
11 To mitigate the ergonomic risk associated with heavy lifting, employers can implement measures such as providing mechanical aids like forklifts or dollies to assist with moving heavy objects, offering training programs on proper lifting techniques, ensuring that loads are properly distributed and packed to minimize weight, and encouraging workers to ask for help when handling heavy items. It's important to note that this is just one example of an ergonomic risk factor related to force, and there can be other situations in various industries where forceful exertions can pose risks to workers' health and safety. 4.2 Vibration Workers are exposed to vibrating hand tools, machines, and the working environment. Two types of vibration hazards: Hand-Arm Vibration and Whole-Body Vibration. These vibrations lead to CTS (HAV) and MSDs (WBV). Examples of activities: hand grinding (HAV), stamping process (WBV). vibration is whole-body vibration (WBV) experienced by vehicle operators. WBV refers to the transmission of vibration through the entire body when sitting or standing on vibrating surfaces, such as operating heavy machinery, driving vehicles, or using power tools. For instance, consider a construction equipment operator who spends long hours operating a vibrating bulldozer. Continuous exposure to whole-body vibration can lead to various health issues, including lower back pain, musculoskeletal disorders, circulatory problems, and fatigue. Prolonged and repeated exposure to WBV can increase the risk of developing conditions like vibration white fingers (Raynaud's syndrome) and even spinerelated disorders. To mitigate the ergonomic risk associated with whole-body vibration, employers can take several preventive measures. These may include: 1. Providing well-designed and ergonomically optimized seats with appropriate vibration damping. 2. Ensuring regular maintenance and inspection of machinery to minimize excessive vibrations.
12 3. Offering frequent rest breaks to allow the body to recover from vibration exposure. 4. Providing anti-vibration gloves or other personal protective equipment (PPE) to attenuate hand-arm vibration (HAV) risks. 5. Conducting training programs to educate workers on the risks of vibration exposure, proper techniques for using vibrating tools or machinery, and the importance of posture and body positioning. Implementing these measures can help reduce the risk of musculoskeletal disorders and other health problems associated with whole-body vibration in occupations that involve prolonged exposure to vibrating equipment or vehicles. Figure 4.3: Hand-Arm Vibration (HAV) Figure 4.4: Whole-Body Vibration (WBV)
13 Figure 4.5: The work environment 4.3 Repetition When motions are repeated frequently (e.g.: every few seconds) for prolonged periods (e.g.: several hours or the whole work shift), fatigue and strain of the muscle and tendons can occur because there is insufficient time for recovery. Table 4.1: Frequency of repetition, task cycle and risk level Body part Frequency repetition per minute Level of risk Very high risk if modified by either Shoulder More than 2.5 times High High external force, speed, high load static, awkward posture Upper arm/elbow More than 10 times High Lack of training, high loads, lack of control Forearm / elbow More than 10 times High Long duration of repetitive Finger More than 200 times High One example of an ergonomic risk factor is repetitive motion. The repetitive motion refers to performing the same task or movement repeatedly over an extended period of time without adequate rest or variation. This can lead to muscle strain, tendonitis, and other musculoskeletal disorders.
14 For instance, consider a data entry clerk who spends long hours typing on a keyboard without breaks or proper ergonomic setup. The repetitive motion of typing can put a strain on the fingers, hands, and wrists, leading to conditions like carpal tunnel syndrome. Without addressing this risk factor, the employee may experience pain, decreased productivity, and potential long-term damage to their musculoskeletal system. To mitigate the ergonomic risk associated with repetitive motion, employers can implement measures such as providing ergonomic keyboards and mice, offering regular breaks or job rotation to allow for rest and variation, and educating employees on proper posture and ergonomics. Figure 4.5: Repetitive motion (Oworkers Office & Delivery Centers, 2021) Minimizing the number of continuous movements can help reduce the risk of injuries if repetitive tasks are necessary. There is no specific number for minimum daily repetitions. The factors affecting repetitive tasks include the user’s muscle strength, the amount of force required, and the type of task. Furthermore, decreasing the amount of force required to complete a task will also lower the risk of pain and musculoskeletal disorders (Scott, O.,Erin, T.,, 2006). Figure 4.5 shows a repetitive motion.
15 4.4 Contact stress Contact stress results from infrequent, repeated, or continuous contact between sensitive body tissue and a hard or sharp object. It affects the soft tissues on the fingers, forearms, thighs, and feet. The contact may create pressure over a small area of the body (e.g.: wrist, forearm) that can inhibit (slow down) blood flow. Example: placing wrists on the sharp edge of a desk while performing the task. Figure 4.6 shown contact stress. Figure 4.7 shows this is an example of a job that involves contact stress. Figure 4.6: Contact stress Figure 4.7: Work with contact stress Contact stress is an ergonomic risk factor that refers to excessive pressure or force applied to a specific area of the body due to contact with an object or surface. It can lead to discomfort, pain, and potential injury, particularly when the pressure is prolonged or repetitive. For example, individuals who work in occupations that involve prolonged kneeling, such as flooring installers or gardeners, may experience contact stress. The pressure exerted
16 on the knees while kneeling can lead to discomfort and, over time, potentially result in knee pain, inflammation, or even chronic knee conditions. To mitigate the ergonomic risk associated with contact stress, employers can implement the following measures: 1. Provide kneeling pads or knee cushions to reduce pressure on the knees when kneeling is necessary. 2. Use anti-fatigue mats or cushioned flooring in areas where employees stand for long periods to reduce pressure on the feet, ankles, and legs. 3. Encourage the use of appropriate personal protective equipment (PPE), such as knee pads or elbow pads, for workers who frequently engage in activities that involve contact stress. 4. Design workstations or equipment with ergonomic considerations, such as padded armrests or cushioned surfaces, to minimize contact stress on specific body parts. 5. Provide training and education on proper body mechanics and techniques to minimize pressure or force during tasks that involve contact stress. 6. Implement job rotation or task variation to reduce prolonged exposure to specific contact stress areas and allow for rest and recovery. By addressing contact stress as an ergonomic risk factor and implementing measures to reduce pressure or force on specific body areas, employers can help prevent discomfort, pain, and potential injuries associated with prolonged or repetitive contact.
17 4.5 Awkward posture Position of the body that deviates significantly from a neutral position. Awkward posture increases effort and muscle force. Example: bending over to lift or grasp an object. Figures 4.8 and 4.9 show awkward posture. Figure 4.8: Workers to bend at significant angles, WMSDs can develop (Creative safety supply, 2023) Figure 4.9: Bending position (Creative safety supply, 2023) Awkward posture is another example of an ergonomic risk factor that can contribute to musculoskeletal disorders and discomfort. It refers to positions or postures that deviate from the neutral or natural alignment of the body, putting strain on muscles, tendons, and joints.
18 For example, consider a cashier who works at a checkout counter with a poorly designed workstation. The cashier may have to reach excessively or twist their body to perform tasks, such as scanning items, bagging groceries, or handling cash. These repetitive awkward postures, such as extended reaching or prolonged twisting, can lead to issues like neck pain, shoulder strain, and back problems over time. To mitigate the ergonomic risk associated with awkward postures, employers can take several measures: 1. Design workstations that promote neutral postures, with adjustable heights and angles for equipment like monitors, keyboards, and cash registers. 2. Provide ergonomic seating with proper back support and adjustability to accommodate different body sizes and postures. 3. Encourage regular breaks and stretching exercises to alleviate muscle fatigue and promote blood circulation. 4. Implement job rotation or task variation to reduce prolonged exposure to specific awkward postures. 5. Provide training and education on proper body mechanics, posture awareness, and techniques to minimize strain. By addressing these factors, employers can help employees maintain healthier postures, reduce the risk of musculoskeletal injuries, and enhance overall well-being and productivity in the workplace. 4.6 Extreme temperature Extreme temperature refers to exposure to excessive cold or hot in the working environment. If workers are exposed to cold temperatures, it can reduce the sensitivity of their hands. As an effect, they may apply more grip force to grip the hand tool. Figure 4.10 shows workers in cold temperatures. For workers who work in hot conditions, it can cause hydration. Figure 4.11 shows workers in hot temperatures.
19 Figure 4.11: Cold Temperature (Tiramillas, 2021) Figure 4.10: Hot Temperature Exposure to excessively high or low temperatures can lead to various health issues and discomfort. For instance, working in extremely hot conditions, such as foundries, kitchens, or outdoor environments during summer, can lead to heat-related illnesses like heat exhaustion or heat stroke. Prolonged exposure to high temperatures without proper hydration and cooling measures can put employees at risk. On the other hand, working in extremely cold environments, such as cold storage facilities or outdoor work during winter, can lead to cold stress and related conditions like frostbite or hypothermia. Cold temperatures can constrict blood vessels, reduce dexterity, and increase the risk of slips and falls.
20 To mitigate the ergonomic risks associated with extreme temperatures, employers can implement the following measures: 1. Provide appropriate personal protective equipment (PPE) suitable for extreme temperature conditions, such as insulated clothing, gloves, or cooling vests. 2. Implement engineering controls like insulation, ventilation, or heating systems to regulate temperature and reduce exposure. 3. Schedule work tasks to minimize exposure during extreme temperature periods, such as avoiding the hottest part of the day in hot environments. 4. Educate workers on the signs and symptoms of heat-related or cold-related illnesses and promote awareness about proper hydration and thermal protection. 5. Encourage frequent breaks in comfortable environments for workers to recover and regulate their body temperature. 6. Establish policies and procedures for monitoring and responding to extreme temperature conditions, including emergency protocols. By implementing these measures, employers can help minimize the risk of heat or coldrelated illnesses, promote a safe working environment, and protect employees from the adverse effects of extreme temperatures. 4.7 Static posture Also known as static loading. It refers to physical exertion in which the same position and posture are held throughout the exertion. It increased loads on muscles and tendons >>> fatigue. Static posture slow-down the flow of blood in the body system. Example: standing in one place for prolonged periods. Figure 4.12 showed the worker in a static posture. Static posture refers to maintaining a fixed body position for an extended period without significant movement. It is considered an ergonomic risk factor because it can lead to muscle fatigue, discomfort, and musculoskeletal disorders. For example, individuals who work at computer desks or perform tasks that require prolonged sitting or standing in the same position may experience static posture-related issues. Sitting or standing for long periods without breaks or postural adjustments can lead to muscle imbalances, strain on the spine, and increased pressure on specific body areas, such as the neck, back, shoulders, and legs.
21 To mitigate the ergonomic risk associated with static posture, employers can take several measures: 1. Encourage regular breaks or provide opportunities for movement and stretching to break up prolonged periods of static posture. 2. Promote postural changes by educating employees about proper ergonomics, including the importance of maintaining neutral spine alignment, adjusting chair and desk heights, and using supportive seating or standing aids. 3. Provide ergonomic furniture and equipment, such as adjustable chairs, standing desks, footrests, and wrist supports, to facilitate optimal body positioning and reduce strain. 4. Implement job rotation or task variation to allow employees to switch between different activities or postures, reducing prolonged exposure to a single position. 5. Conduct ergonomic assessments and provide individualized recommendations to employees based on their specific tasks and workstations. 6. Offer training programs on posture awareness, body mechanics, and exercises that help improve posture and strengthen supporting muscles. By addressing static posture as an ergonomic risk factor and implementing measures to promote movement and postural changes, employers can help reduce the risk of musculoskeletal disorders, improve comfort, and enhance overall well-being in the workplace. Figure 4.12: Static posture (Ergolink, 2022)
22 5.0 Ergonomics Controls Three ergonomics control. To reduce the chance of injury, work tasks should be designed to limit exposure to ergonomic risk factors. Where possible, Engineering controls are the most desirable. Administrative or work practice controls may be appropriate in some cases where engineering controls cannot be implemented or when different procedures are needed after the implementation of the new engineering controls. Personal protective equipment (PPE) solutions have only limited effectiveness when dealing with ergonomic hazards. 5.1 Engineering Control Physical changes to jobs that control exposure to risk. Engineering controls act on the source of the hazard and control employee exposure to the hazard without relying on the employee to take self-protective action or intervention. Examples: Changing the handle angle of a tool, using a lighter weight part, and providing a chair that has adjustability. Figure 5.1: Materials handling Figure 5.1 showed an example of engineering control, Mechanical devices that lift and tilt to adjust materials for easier handling.
23 Figure 5.2: Lifting the barrel Figure 5.3: Dispose of garbage Work activities that involve lifting things are a constant occurrence. This activity is important and puts pressure on the body parts. Incorrect posture can cause injuries. Engineering control. Engineering control is very helpful for employees in the work process. This involves a high cost of producing the machine. Figures 5.2 and 5.3 show examples of machines that help workers in their jobs. High-profile companies, don't face cost problems in buying machines or making new innovations to help employees at work. BEFORE AFTER
24 Position Hand Tool for drilling (Middlesworth, 2023) Bent wrist – Poor Wrist Position Straight Wrist – ideal Wrist Position Bent Wrist – Poor Wrist Position Straight Wrist – Ideal Wrist Position Figure 5.4 : Hand Tool for drilling
25 5.2 Administrative/ work practice Control Altering work organization. Procedures and methods, set up by the employer, that significantly reduce exposure to risk factors by altering the way in which work is performed. These approaches usually are less expensive than engineering controls but are less dependable. Example: Don’t do one thing too long, employee rotation, job task enlargement, and adjustment of the workplace. Figure 5.5: Flowchart Administrative/ Work Practice Controls Figure 5.6: Work Practice Controls
26 Figure 5.7: Example Control Hazard In the workplace to decrease or limit exposure to a specific hazard, administrative controls (also called work practice controls) are used. Changing how work is done when elimination, substitution, or the use of engineering controls is not feasible, in this kind of hazard control work. In the Hierarchy of Controls, administrative efforts rank fourth for effectiveness and efficiency. Administrative controls are not seen as effective as other controls because it is at risk for human error and is typically used as a temporary solution rather than a sustainable, long-term solution. Examples of administrative controls include the state by (Creative safety supply, 2023): 1. Training: Working around the hazard, workers should be trained to identify hazards, monitor hazard exposure, and safe procedures. Additionally, employees should know how to protect themselves and their co-workers. 2. Procedures: The worker from encountering the hazard, the steps in a job process may need to be rearranged or updated to keep. Developing standardized safe work practices is an important step. 3. Maintenance: To keep everything running smoothly and safely having a maintenance schedule for machines known to be hazardous can. Preventive maintenance will address any equipment issues before they become a problem. 4. Housekeeping: To minimize the severity of an accident, sustaining a clean and clutterfree space will greatly reduce the risk of injury and can. 5. Signs: Wall signs and floor signs can be posted or installed to enforce administrative controls. Visual cues can remind workers which areas are prohibited from entering when breaks need to be taken to limit heat exposure, and much more.
27 5.3 Work practice control 1. Proper lifting technique 2. Good postures 3. Alternate repetitive tasks 4. Use breaks to divide up ‘heavy’ work 5. Stretching / exercise 5.3.1 Maintain Neutral Posture Neutral postures are postures where the body is aligned and balanced while either sitting or standing, placing minimal stress on the body and keeping joints aligned. Neutral postures minimize the stress applied to muscles, tendons, nerves, and bones and allow for maximum control and force production. The opposite of a neutral posture is an “awkward posture.” Awkward postures move away from the neutral posture toward the extremes in a range of motion. This puts more stress on the worker’s musculoskeletal system, is a contributing risk factor for Musculoskeletal Disorders (MSDs), and should be avoided. Figures 5.7, 5.8, and 5.9 show neutral and awkward posture. Figure 5.8: Neutral Posture VS Awkward Postures for Hand (Middlesworth, 2023)
28 Figure 5.9: Neutral Posture VS Awkward Postures for Shoulder (Middlesworth, 2023)
29 Figure 5.10: Neutral Posture VS Awkward Postures for Standing (Middlesworth, 2023) Modify Tasks: Alternate activities frequently; rotate heavy &/or repetitive tasks w/ lighter less repetitive ones. If become worse, look for alternative methods. Avoid repetitive or prolonged grip activities. Take frequent breaks to stretch & rest your hands. Figure 5.9 show posture correct & incorrect techniques.
30 Correct & Incorrect Techniques Figure 5.11: Posture Correct & Incorrect Techniques (Middlesworth, 2023) 5.4 Personal Protective Equipment (PPE) Personal protective equipment, commonly referred to as "PPE", is equipment worn to minimize exposure to hazards that cause serious workplace injuries and illnesses. All personal protective equipment should be maintained in a clean and reliable fashion because safely designed and constructed. It should fit comfortably, encouraging worker use. When engineering, work practice, and administrative controls are not feasible or do not provide sufficient protection, employers must provide personal protective equipment to their
31 workers and ensure its proper use. Employers are also required to train each worker required to use personal protective equipment to know: ▪ When it is necessary ▪ What kind is necessary ▪ How to properly put it on, adjust, wear, and take it off ▪ The limitations of the equipment ▪ Proper care, maintenance, useful life, and disposal of the equipment Use protection to reduce exposure to ergonomics-related risk factors. Figure 5.10 show examples: Use padding to reduce direct contact with hard, sharp, or vibrating surfaces. Wear good-fitting thermal gloves to help with cold conditions while maintaining the ability to grasp items easily. Figure 5.12: Example of Personal Protective Equipment (Catalogue Solutions Ltd, 2023)
32 5.5 Hierarchy of Control The hierarchy of controls is a method of identifying and ranking safeguards to protect workers from hazards. They are arranged from the most to least effective and include elimination, substitution, engineering controls, administrative controls, and personal protective equipment. Figure 5.13: Hierarchy of Control Figure 5.14: Effectiveness of control ENGINEERING CONTROLS • Buy Quiet • Vibration Pads • Enclosures • Barriers • Isolation ADMINISTRATIVE CONTROLS • Rotate Workers • Extended Breaks • 2 nd/3rd Shift PERSONAL PROTECTIVE EQUIPMENT
33 Engineering control is the most effective, followed by administrative and work practice control, and finally PPE in the hierarchy of Control. (Ergolink, 2022) 6.0 Various Ergonomics in Design. In a workstation, there are various sizes of workers and various types of tasks performed. therefore, the design variations of the workplace and equipment are designed according to the task and are flexible according to the employee himself. Equipment used fit for workers. Figures 5.11 and 5.12 show various designs for workstations. Figure 5.11: Production line (JOT, 2009) Figure 5.12: Workstation Laboratory (JOT, 2009)
34 EXERCISE 1. Define the term ergonomic and list THREE (3) types of industries that applied ergonomics. 2. List TWO (2) domains of specialization within the discipline of ergonomics. 3. State the purposes of ergonomics in design. 4. Describe the contributions of ergonomists to ensure workers are compatible with the needs, abilities, and limitations of the workplace. 5. Distinguish between Hand-Arm Vibration and Whole-Body Vibration. 6. Explain THREE (3) types of ergonomic control. 7. Explain why engineering control is the most effective way to control the ergonomic risk factors at work. 8. Explain neutral postures and explain their benefits to the human body. 9. Explain about posture. 10. Explain awkward postures and their effect on the human body. TUTORIAL 1. What is Ergonomics? Answer Ergonomicsis the study of the relationship between the employee and the workplace. It is a developing body of knowledge whose goal is to provide and maintain a healthy “user-friendly” environment. Ergonomics is about ’fit’: the fit between people, the things they do, the objects they use, and the environments they work, travel, and play in. If a good fit is achieved, the stresses on people are reduced. 2. Give the suggestion for ergonomics solutions to awkward posture below:
35 Answer: (Jishin Jayan Thrippunath, 2023) 3. How to reduce ergonomics risk? Answer: Engineering Improvements. Engineering improvements include rearranging, modifying, redesigning, or replacing tools, equipment, workstations, packaging, parts, or products. These improvements can be very effective because they may reduce or eliminate contributing factors. (For example, if your job requires sitting for long periods of time, having an adjustable seat or footstoolso that your knees are higher than your hips helps protect your lower back.) Administrative Improvements. Administrative improvements include changing work practices or the way work is organized. •Providing variety in jobs •Adjusting work schedules and work pace •Providing recovery time (i.e., muscle relaxation time) •Modifying work practices •Ensuring regular housekeeping and maintenance of workspaces, tools, and equipment •Encouraging exercise Personal Protective Equipment. Safety gear, or personal protective equipment (PPE), includes gloves, knee and elbow pads, footwear, and other items that employees wear.
36 References Creative safety supply. (2023). Administrative Controls. Retrieved from Creative safety supply: https://www.creativesafetysupply.com/about/ Ergolink. (2022). 5 Ways Good Workplace Ergonomics Can Reduce Static Posture. Retrieved from Ergolink: https://www.ergolink.com.au/blog/5-ways-good-workplace-ergonomics-canreduce-static-posture Gokhan, U., Ozge, G. (2022). A Comparative Analysis on Ergonomics of University Libraries: A Case Study. Online Journal of Art and Design volume 10, issue 3, 245 - 262. Jan, D., Bernard, W.(2008). Ergonomics for Beginners: a quick reference guide. USA: CRC Press Taylor & Francis Group. Jishin, J., Thrippunath, M. Z. (2023). Implications of Ergonomic Health Risks on Workers and Ergonomic Risk Assessment: A Review Study Based on Different Industry Contexts. J Med Glob, 149-154. JOT. (2009). Pfeiffer Vacuum schliebt Investitions projekt ab. Retrieved from JOT: https://www.jotoberflaeche.de/branche/pfeiffer-vacuum-schliesst-investitionsprojekt-ab-2001194.html Middlesworth, M. (2023). 8 Fundamental Ergonomic Principles for Better Work Performance. Retrieved from Ergoplus: https://ergo-plus.com/fundamental-ergonomic-principles/ Neville, S., Mark, S. (1999). Guide to Methodology in Ergonomics: Designing for Human Use. Computer Science. OshAcademy. (2023). Course 619 - Materials Handling Safety. Retrieved from OshAcademy: https://www.oshatrain.org/courses/mods/619m1.html# Oworkers Office & Delivery Centers. (2021). Key Skills Of a Data Entry Clerk. Retrieved from OWORKERS: https://oworkers.com/key-skills-of-a-data-entry-clerk/ Personal Protective Equipment Guidance Safety Poster. (2023). Retrieved from RS Component: https://export.rsdelivers.com/product/rs-pro/personal-protective-equipment-guidancesafety-semi/9011387 Scott, O., Erin, T.(2006). Ergonomics and Design A Reference Guide. Allsteel Inc. Tanya, M. T., Banakar, R. (2018). Data transfer protocols in IoT-an overview. International Journal of Pure And Applied Mathematics, 1-6. Tiramillas. (2021). This is Oymyakon: The coldest habitable place on earth where temperatures reach -71.2 degrees. Retrieved from MARCA: https://www.marca.com/en/lifestyle/2021/01/09/5ff9eb8aca4741cd178b45f5.html
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