Stressors Noise

Main forms of physical stressors noise, temperature, light vibration and repetitive strain radiations. Main effects on the body. 

Most of the research on the effects of these stressors on human performance has been done on simple laboratory tasks rather than actual work situations. As a result, the extent that such findings can carry over to tasks in the CPI is debatable. In addition, most of these studies have examined the effect of a single stressor (e.g., noise or heat) only, rather than the combined effect. Nevertheless, some useful guidelines about optimal levels of these stressors are available in the ergonomics literature (e.g., McCormick and Sanders, 1983 Salvendy, 1987). 

Prabhakaran et al. indicated that noise could be a potent stressor and cause disturbances in the biochemical parameters of the body. It is presumed that most of the effects are indirect, being manifested through the activation of autonomic nervous system that liberates catecholamines and HPA axis responsible for the liberation of corticosteroids [104], In 1989, Hershock and Vogel found that in male Sprague-Dawley rats, acute immobilization stress could affect serum triglyceride and nonesterified fatty acid values and that these effects were diet and time dependent however, the rats total cholesterol levels were unaffected by stress [105], In addition, in 1996 Brennan et al. pointed out that stressed animals had higher levels of the cholesterol parameters than did home cage controls [106],... 

Early warning indicator Rapid identification of potential effects. Use when endpoint is slow to respond or has delayed effect minimal time lag in response to stressor and rapid response rate low signal to noise ratio of the measure and low discrimination screening tool and false positives acceptable. 

Sensitive indicator Reliability in predicting response. Use when endpoint is relatively insensitive high stressor specificity and high signal to noise ratio minimizes false positives. 

Glass, D. C. and Singer, J. E. (1972). Urban Stress Experiments on Noise and Stressors. New York Academic Press. 

For environmental stressors, reduce contact with the stressor. Use a cool recovery acea to recover from heat, a quiet area to recover from noise, no vibration to recover from vibration. For muscle stressors, it helps to have a good circulation system (to be in good shape). Active rest seems better than passive rest. The active rest may be just walking to the coffee area (blood circulation in the legs improves dramatically within <20 steps). Another technique to get active rest is to have the operator do the material handling for the workstation (obtain supplies, dispose of finished components). 

The assessment of environmental stressors sueh as noise, drugs, or sleep loss. 

The task has to be executed under the influence of environmental stressors, such as heat, noise, vibration, or working at night, which may disrapt the energetical state of the employee physically. These are direct effects on the organism and ate not mediated via cognitions or emotions as is the case with stress reactions. 

Controlling or eliminating environmental stressors (i.e., inappropriate temperature, humidity, light, noise, aggressive cage mates, cage size). 

The circrrmstances or sitirations that induce stress responses are defined as stressors (Auerbach and Gramling, 1998). Green et al. (1996) outlined foiu types of pilots stressors, these are environmental stressors, domestic stress, work stress, and life stress. On the flight deck, environmental stressors specifically consist of excessive heat, noise, vibration, and low humidity. 

The lack of job security has become very real with so much reorganizing and downsizing transpiring in the business community. Career pressures including increased responsibility are viewed as stressors by many workers. Some workers have jobs that are too complex for their talents, abilities, or skills. Last, but by no means unimportant, is the physical environment such as noise, temperature extremes, lighting, space, and odors. Other work environment stressors are... 

Environmental stressors such as extremes of temperature, noise, vibration, bodily injury, hunger, etc. all have both physiological effects as well as psychological effects. 

What you have read above has dealt with mat r of the workplace sources of disease, disability and ill health. These sources as we noted earlier are called stressors . Each stressor affects particular target cells, organs, tissnes or systems in the body. For information on noise, vibration and ionizing radiation as stressors, see Chapter 10. 

Take part in the measurement of a workplace stressor (chemical or plysical, e.g. noise). 

Some of the psychological stressors that directly affect mental stress are suddenness of onset duration of stress task speed task load high-jeopardy risk threat of failure boring, repetitive, or meaningless work long, uneventful vigilance periods and distractions (e.g., noise, glare, and flicker). 

Following measurement of the individual stressor, evaluation can be made against known hygiene standards, e.g. Occupational Exposure Limits, noise action levels specified in the Noise at Work Regulations 1989. 

All five tools included environmental stressors but apart from THERP, none went in to any detail, i.e. the four remaining HRA tools simply listed environmental conditions as a PSF. THERP provided more specific PSFs including temperature extremes, radiation, oxygen insufficiency, and vibration. However, THERP did not cover less extreme environmental conditions such as lighting levels, glare, and noise. 

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