Section – A
- a) ‘Ergonomics’ is the approach of studying individuals within their work environment. Essentially, it studies the human factors and their interactions with other elements of the work system (UNC, 2022). The three primary ergonomic stressors are the force required for the completion of any task, static postured adopted by the employee while working on the completion of the task, and the amount of repetitiveness of the task (UNC, 2022). The ergonomic assessment of the task is done from the physiological, biomechanical and physical perspectives and involves maximizing safety and efficiency within the workplace.
Ergonomic interventions are in three areas, namely, the physical, organizational and cognitive (Dennerlein, 2017). The work atmosphere and environment are adjusted for enhancing human capacity and working capabilities by focusing on aspects of the work environment through an ergonomic intervention (Panjaitan & Ali, 2019). Potential ergonomic risk factors, such as static postures, repetitive motions, forceful exertion, heavy lifting, etc., can be identified through ergonomic interventions (Tee et al., 2017). Without such interventions, workers are exposed to various musculoskeletal disorders. The interventions aim to design such systems, processes and products that minimize human errors and their risk to injury. Examples of ergonomic approaches include a commitment from management, identification of hazards, employee involvement and control, training and program evaluation (Dennerlein, 2017). Enhanced scientific designs of equipment help prevent potential injuries to employees. Also, when employees feel physically comfortable in their environment, they are likely to be more productive in their work and sustain the job in the long haul (Deouskar, 2017). In this regard, ergonomics approaches aim to build around the capacity of the workers for the purpose of maximizing their efficiency and capabilities. For designing equipment, data is collected from various branches in a manner that can help modify or design the equipment for benefiting the workers. This includes industrial design, informational design, physiology, biomechanics, environmental physics, etc.
The physical ergonomics approach is with regards to workplace ergonomics and takes into consideration the anthropometric, anatomical, physiological, and biomechanical aspects of the workplace. The jobs are designed as per this approach in a manner that is suited to the capabilities of the workers and helps prevent any musculoskeletal disorders in the workplace (Goonetilleke & Karwowski,2017). This form of approach takes into consideration working postures, keyboard design, portable devices, repetitive motions, materials handling, etc. An example of the approach is shown in figure 1. Another approach is that of cognitive ergonomics, which takes into consideration the mental processes of the workers, such as memory, reasoning, motor response, as they are capable of impacting the human interactions that the worker has. Cognitive ergonomics is essentially concerned with the usage of machinery and its compatibility with the cognitive abilities of the worker using the machinery (Kalakoski et al., 2020). Any form of cognitive disruption can lead to a task performance that is impaired and also lead to reduced wellbeing of the worker. An example is taking into consideration the designing of the tasks, wherein the work demands may be too high or low, there may be contradictory demands of high productivity and quality, etc. (HSE, 2013). In such cases, the work is designed in a manner that suits the cognitive capabilities of the worker.
Figure 1: Physical Ergonomics (Source- https://www.physio-pedia.com/Ergonomics)
A third approach of ergonomics is organizational ergonomics which aims to optimize the social-technical systems within the organization. These include the organizational structures, policies and processes. Examples are job shifts, schedules of workers, ethical conduct within the workplace, teamwork, etc. This approach is also known as macro ergonomics (Holden et al., 2015). The macro ergonomics approach is one that is design-driven and takes a systems approach. This implies that performance is improved through the means of designing such systems that are supportive of the capabilities and work responsibilities of the workers (Holden et al., 2015). This is essential for improving the productivity, innovativeness, flexibility, safety and sustainability of the workers of the organization. Through such approaches, ergonomics aims to focus on the physical work being done by the workers, their cognitive capabilities and their social environment.
The physical and cognitive characteristics of the workers are an important aspect of ergonomics as the primary aim of all ergonomics approaches is ensuring workers are safe, and their risk to any form of injuries is minimalized. As per the posture, body size and shape, fitness, knowledge, training, experience, etc., of the individual, the systems are designed to suit the physical and cognitive needs of the individual. Therefore, ergonomics shapes the environment of the worker to better suit their capabilities and ensure their safety, efficiency and comfort are maximized.
b) Ergonomics approaches aim to help reduce human error. Human errors can occur in the form of slips and lapses, mistakes, or violations. While slips and lapses are errors that were not planned by the worker and occurred while undertaking a familiar task due to a slip on the part of the worker, mistakes are errors in the judgment of the worker which impact their ability to make the right decision (HSE, n.d.). Violations occur when the worker consciously chooses to not comply with the workplace’s procedure. However, human failure is predictable in nature and can be managed through appropriate ergonomics.
Inadequate organizational structures and systems can cause the worker to be distracted and, in turn, be a cause for human error. An example of this is shown in figure 2. Any distractions from the organizational environment can be due to processes that make it difficult for the employee to adequately focus on the job at hand or due to poor products or machinery that are difficult to operate. By creating such organizational systems and structures that remove the technical and organizational distractions, the worker can adequately receive important information related to their work, process it and deliver an error-free performance (Butlewski et al., 2014). Factors such as noise, lighting, vibrations, etc., may have to be removed from the material environment so that the employee is not distracted easily. Other factors such as pace of work, supervision, etc., also have to be taken into consideration. By identifying the different types of distractions that cause human errors, they can be removed through the enforcement of adequate workplace systems that minimize the distractions and thus, in turn, also help minimize human errors.
Figure 2: Reasons for External Human Errors (Source –Butlewski et al., 2014).
In conclusion, any ergonomics approach can help minimize the chances of human error while also making the workplace system more compatible with the work of the employee and helping the employee become more productive.
- Exposure to extremely loud sounds can cause damage to the inner ears of the individual and result in hearing loss within that individual. This is referred to as noise-induced hearing loss (CDC, 2021). It damages the structures and nerve fibres within the inner ear and may require medical assistance for it to be corrected. This occurs as a result of a single exposure to an extremely loud sound such as a blast or from exposing oneself to loud noises for an extended period of time. The auditory nerves of the individual carry the sound waves within the air as electric signals to the human’s brain, so that the human may be able to understand and comprehend the sound.
Overstimulation of the sound-sensitive cells or the sensory neurons within the ear canal leads to hearing impairment which is known as ‘noise-induced hearing loss’. It has been recognized as an occupational disease in certain occupations, such as copper workers that hammer on metal on a continuous basis and are thus exposed to loud noises in the process (Le et al., 2017). On the basis of the intensity of sound and the length of the exposure, noise trauma can either be a permanent threshold shift or a temporary threshold shift (Le et al., 2017). The loud noise enters the external auditory canal of the ear and goes through the eardrum. The intensity of the noise causes the eardrum or tympanic membrane to vibrate. This, in turn, causes the malleus, middle ear ossicles, incus and staples to also vibrate with the same intensity. The auditory signal causing the distress is amplified because the middle ear ossicles send mechanical energy to the cochlea through the means of the staples footplate. The staples footplate hammers over the window of the cochlea and the fluid within the organ to be displaced (Prell et al., 2007). This displacement causes a type of movement within the sensory cells of the cochlea. The cells within the cochlea become damaged as a result, and the individual suffers from hearing impairment which is known as noise-induced hearing loss. Figure 3 shows the process of noise-induced hearing loss.
The force and intensity with which the pressure of the noise goes through the basilar membrane of the cochlea either causes a sensory overload, cell damage or cell death.
Figure 3 – Noise Induced Hearing Loss (Source – Cleveland Clinic, 2021).
The individual may hear a type of buzzing within their ear or may feel intense pressure within the ear as a result of the damage caused to the sensory cells within the cochlea. While this can last temporarily for a number of days, the loss can also cause permanent damage to the cells of the inner ears (Cleveland Clinic, 2021). Figure 4 shows how the various decibels of sound are comprehended by the human ear. Any noise beyond 80dB can impact one’s hearing harshly (Cleveland Clinic, 2021). Examples of sounds that can cause noise induced hearing loss are sounds made by gas powered lawnmowers, gun fire, loud music, etc. ( CDC, 2021). A single exposure as well as continuous exposure to loud sounds can cause the problem. This is why the use of hearing protection devices is necessary when being exposed to loud sounds continuously (CDC, 2021).
Figure 4- Threshold of Hearing for Human Ears (Source - https://www.livingsounds.ca/blog/noise-induced-hearing-loss/)
- Noise can be hazardous within the workplace if the pitch and frequency exceed a certain limit, as this is capable of causing damage to the inner ear of the workers and can also result in permanent noise induced hair loss. Figure 5 shows the various control mechanisms that can be used for managing noise exposure during work with the top most routes being the most efficient for management of hazardous noise at the workplace.
Figure 5- Hierarchy of controls for Noise exposure (Source -https://www.af-acoustics.com/noise-control/)
Any type of noise level which exceeds 85 decibels over an eight-hour shift is considered to be hazardous in nature. This is the usual work hour shift period, and noise with such frequency is considered to be hazardous to the safety of the employees (OSHA, n.d.). These set the occupational exposure standards for noise in most industries. One of the primary mechanisms for achieving this can be through the purchase of low noise tools and machinery. This ensures equipment is engineered and designed in a manner that fits the needs of the workers adequately for performing the tasks in the organization while also helping ensure noise is created within the occupational exposure standards for noise (CCOHS, 2022). Engineering modifications could include modifying the path of the sound in a manner that ensures it does not act as a hazard or by including protection from the noise if it was not included in the initial design stage of the noise-producing equipment used by the workers (CCOHS, 2022). Metal on metal impacts should be avoided, such as abrasion-resistant rubber on line chutes. Usually, the mechanism for control of the noise at the source rather than at the path of the noise should be the preferred mechanism. The noise which is produced as a result of vibrations should be used through engineering controlling mechanisms. This includes reducing the force of the impact or the speed of the fan of the equipment that causes vibration-induced noise (CCOHS, 2022). An example of avoiding turbulence is shown in figure 6.
Figure 6- Avoiding turbulence (Source - https://www.ccohs.ca/oshanswers/phys_agents/noise_control.html)
Regular maintenance of tools is necessary, and routine checks on the equipment must be undertaken to ensure they do not produce noise over the acceptable limit of noise production (CDC, 2018). One of the mechanisms for this is ensuring the lubrication of gears.
Another mechanism is that of substituting the noise-producing machinery with alternatives that are quieter and produce the noise within the legal noise exposure limit. This can help in making the workplace environment less noisy and should always be taken into consideration by the employer in case the source of the noise cannot be eliminated (IOSH, n.d.). If there are mechanisms for performing the task in a different way, these should also be taken into consideration by the employer. For example, in construction, hammering produces more noises as compared to the use of hydraulic processes (IOSH, n.d.). Instead of fuel-based engines, electric engines can be used. Also, electrical tools can be used instead of pneumatic tools, and rubber tyres can be used instead of solid wheels. The employer should ensure substitutes and alternatives to noise-producing equipment are used wherever possible.
Administrative controls for controlling the exposure of the workers to the noise can also be put in place. This can include putting restrictions on the number of hours that workers can spend in a noisy area in a single shift. It also includes mandating the use of personal protective equipment for workers so that their ears are protected from loud noises. Usually, a combination of both administrative measures and personal protective gear is used to ensure the exposure to the source of noise is not hazardous (CCOHS, 2022). The use of personal protective equipment is usually considered to be the last option in the hierarchy of controls for noise control mechanisms and is put into place when noise levels cannot be controlled through technical means or through administrative means (IOSH, n.d.). Ear defenders and other hearing protection devices can be used for protecting the workers against the noise (IOSH,n.d.). The hearing equipment for the protection of the workers should be made readily available, and workers should be given sufficient instructions on how the equipment is to be used. These should be provided at a no-cost basis to the workers, so that the real world exposure of the workers to noise is minimal and under 85dBA. These are a form of administrative control of the noise that the workers are exposed to. Proper noise assessment must be done by the organization to ensure the correct type of hearing protection or personal protection equipment is put into place for the workers that are regularly exposed to heavy noises (IOSH, n.d.). Through these means, occupational noise exposure standards can be achieved.
1. Accidents in the workplace are either a result of ‘active failures’ or ‘latent failures’. While active failures are a result of the violations of front line workers, latent failures are those conditions within the organization that raise the likelihood of active failures.
The consequences of ‘active failures’ are immediate and are a result of the violations of the front line workers. These can be machine operators or control room staff (HSE, n.d.). These can have an immediate consequence on the safety of the individuals within the workplace. These consequences can be prevented through appropriate designs, implementation of operating standards, enforcing best practices within the workplace, adequate training of front line workers (Aird, 2019). These failures are essentially violations on the part of the front line workers and can have a detrimental impact on the individuals within the organization. They are essentially a breach of the various safety defences within the organization, and that is why usually front line workers are responsible for the occurrence of such failures (Florio, 2016). They can comprise of both actions as well as inactions on the part of the front line workers. In terms of the component of human failures, either there can be errors or violations. An error can occur on the part of the worker when they do not consciously choose to cause the failure, while violations can occur when the workers willingly choose to not comply with the established safety processes and procedures of the system (Florio, 2016). Examples of active and latent failures are shown in figure 7.
Figure 7 – Active and Latent failures within the organization (Source - https://www.researchgate.net/figure/Active-and-latent-failures-and-their-contribution-to-the-breakdown-of-complex-systems_fig2_220055149)
Latent failures are due to the faults of individuals who do not have a direct impact on operational activities, such as decision-makers within the organization, managers, etc. (HSE, n.d.). These are usually the categories of failures that are a part of the implementation, monitoring or design of the safety management systems of the organization (HSE, n.d.). These are usually less apparent as compared to the active failures as active failures are circumstantial and can be immediately identified. Some examples of latent failures are inefficient communications within the organization, inadequate supervision from the supervisors of the frontline workers, poor design of the equipment used within the organization. It can be noted that they can indirectly be the cause for active failures within the organization (Florio, 2016). These could result in conditions that eventually cause active failures and have been present within the system for a very long time. They are not immediately considered to be harmful, but the harmful impact of the latent failures become evident once the system’s defences are eventually breached (Florio, 2016). A lack of a strong safety culture is one of the major reasons for the prevalence of latent failures within the organization. Organizational processes and procedures have to be closely monitored for the purpose of identifying latent failures so that active failures, in the long run, can also be avoided (Florio, 2016). Latent failures are a result of the organizational culture and supervisory inadequacies within the organization. Latent failures can be controlled through the creation of a work environment that creates a high risk for an individual who violates any of the organizational rules, while the risk for an operator being involved in slips and lapses is reduced (Florio, 2016).
The active and latent failure models show how individuals can either be contributories to an accident within the organization or be the cause for the accident (HSE, n.d.).
For the purpose of upholding the safety defences of the organization, preventing both latent and active failures is necessary. System processes must be monitored to identify and prevent latent failures. The prevention of latent failures will, in turn, also ensure the likelihood of active failures decreases within the organization.
1. Accident investigation plays an important role in the management of occupational health and safety. It is crucial for ensuring future incidences do not take place, and strong corrective actions can be undertaken for ensuring the same. It helps in the identification of the faulty elements of the system and provides an opportunity for learning and improving. Accident investigations help determine if efficient plans for safety control are in place within the organization. Findings from accident investigations can help create plans that reduce the overall risk management system of the organization, thus improving organizational safety (HSE, 2004).
An ‘accident’ is an event that causes any type of injury to an individual or a group of individuals within the workplace (HSE, 2004). In worst-case scenarios, it can also have fatal consequences, such as death. Other consequences can be major injuries that cause amputation or loss of sight of the individual. Serious injuries can also take place, wherein the individual is not fit for work for the next few consecutive days. Lastly, minor injuries and damage to organization property can also occur (HSE, 2004). Accident investigation involves identifying the ‘why’ and the ‘how’ of the accident. It also helps enforce the essential actions which can help prevent the event from occurring again (International Labor Office, 2015). For this purpose, the investigation comprises of six questions which are the 1H and 5Ws. These questions help in the root cause analysis and are as follows–
- ‘When’ did the incident take place?
- ‘Where’ did the accident take place?
- ‘Why’ did the accident occur?
- ‘What’ happened at the time of the occurrence of the accident?
- ‘Who’ were the parties that were injured as a result of the accident?
- ‘How’ did the incident occur? (International Labor Office, 2015).
Asking the first 1H and 5Ws can help determine the cause of the accident and help undertake an analysis of the accident, so that it can be prevented in the future. The investigation is ‘reactive’. This is so because the investigation takes place after the occurrence of the accident, and safety control measures are enforced according to the analysis of the investigation. Accident investigations also take place due to the regulatory requirements mandating the same, but are also essential for determining the level of corrective actions that need to be taken for repairing the detrimental impact of the accident (HSE, 2004). Furthermore, human error is also identified through such an investigation which may have caused the accident. There may either be active failures that caused the accident to occur or latent failures that caused the accident to take place. The immediate causes for the accident, as well as the underlying causes of the accident, can be discovered through the means of the investigation. While the immediate cause could be some form of error or violation on the part of the workers, the underlying cause can be a lack of supervision or management (International Labor Office, 2015). After the investigation, penalties can be applied to the appropriate individuals who were responsible for the accident. Health hazards can also be identified and can be removed from the workplace so that the safety of the workers is not put to risk in the workplace (International Labor Office, 2015).
An efficient accident investigation plan will comprise of a structured approach to gathering and analyzing information related to the accident, so that the information may be efficiently utilized. Accident investigation can either consist of a root cause analysis which is an extremely formal investigation of the incident or an apparent cause analysis which is a less formal investigation (AICHE, n.d.).The causes of the accidents are investigated through such methods and a limited number of causes may be identified depending upon the form of analysis or investigation being undertaken. Lessons learned through the accident evident in the standard incident report help ensure the risk of similar accidents in the future is minimized. Accidents may be evaluated through the relevant form of method depending upon their categorization within the organization (AICHE, n.d.).
Figure 8 – Root Cause Analysis (RCA) and Apparent Cause Analysis (ACA) (Source - https://www.aiche.org/ccps/introduction-incident-investigation)
In conclusion, an accident investigation is crucial for preventing future accidents and for the purpose of identifying who was responsible for the accident. It also helps take immediate corrective action aimed at helping those parties that were injured as a result of the accident while also taking preventive actions so that future accidents can be avoided.
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