Workplace Ergonomics Risk Factors for Computer User
Posted Sep 27 2008 8:49am
What is an Ergonomics Risk Factor? Specific causes of Cumulative Trauma Disorders (CTDs) in the workplace are often difficult to identify because many ergonomics risk factors may interact simultaneously to bring about or aggravate the condition. It also may be difficult to isolate occupational factors from non-occupational factors or leisure activities and individual susceptibility (possible hereditary traits).
However, let’s start by defining what an ergonomics risk factor is. An ergonomics risk factor is any attribute, experience or exposure that increases the probability of the occurrence of a disease or disorder, although it is not necessarily a causal factor. Ergonomic risk factors can cause, aggravate or precipitate Cumulative Trauma Disorders. However, it is important to note that the mere presence of an ergonomic risk factor does not necessarily mean that the employee performing the job is at an excessive risk of injury.
Dose-Response Relationship The dose-response relationship refers to the specific outcome following an exposure to a specific agent or ergonomic risk factor. The outcome resulting from the exposure to ergonomic risk factors refers to any adverse health effect, and may range from acute injury to long-term disease and loss of function. In general, a higher frequency and longer duration of exposure to single agent or ergonomic risk factor, is found to be positively correlated with the development of a particular outcome. This relationship is true also with ergonomic risk factors. Hence, prolonged or repeated exposure to an ergonomic risk factor increases the likelihood of developing a musculoskeletal injury or Cumulative Trauma Disorder.
An exact dose-response relationship of ergonomic risk factors has not yet been established. However, the more ergonomic risk factors that are present, the higher the level of risk is for developing consequent injury. In fact, according to the National Safety Council, it is possible that the interaction between various ergonomic risk factors has a multiplicative effect instead of an additive. The multiplicative effect, in effect significantly increases the likelihood of disease development with multiple ergonomic risk factor interaction. Having more than one ergonomic risk factor present significantly increases the probability of incurring micro-trauma. On the other hand, if the identified risk level is low or there appears a sufficient provision of rest or recovery time, the actual risk may be minimal. Most importantly, reducing the amount of ergonomic risk factors present will reduce the occurrence of Cumulative Trauma Disorders.
Computer-Related Ergonomic Risks The recent literature identifies the following Occupational and Non-occupational Ergonomic Risk Factors as potential risk factors leading to work related injuries or Cumulative Trauma Disorder for computer users. The most important contributing factor to the development of Cumulative Trauma Disorders is the production of local tissue fatigue and micro trauma, as the working tissues are overloaded. Sufficient blood supply is the most important factor in controlling tissue overload and fatigue. By maintaining an adequate supply of oxygen-enriched blood to working tissues, metabolic efficiency can be maintained, thus minimizing the adverse effects of fatigue and preventing excessive micro-trauma. The key to maintaining adequate blood flow to active tissues is in the balance of the relationship between work and human physiology. These ergonomic risk factors increase the likelihood of developing fatigue and micro trauma because they may impair blood flow to the working tissues.
Computer-Related Ergonomics Risk Factors These computer-related ergonomic risk factors increase the likelihood of developing fatigue and micro trauma because they may impair blood flow to the working tissues due to the use of computers. Computer-related ergonomic risk factors include: high task repetition, static work, posture and mechanical pressure. The following section describes each computer-related ergonomic risk factor and provides various methods for controlling or reducing the level of risk. As the level of risk for each ergonomic risk factor is reduced, the likelihood of injury development is also reduced.