The aim of occupational health can be summarised as "The adaptation of work to main and of each man to his job. "This implies that the physical and mental capacities of the individual has to be matched with the demands of the job. Vision is one of the most important attribute of man which has to be matched according to the job to improve work efficiency. Good eyesight can be directly linked to efficiency and safety, leading to increased productivity..
The role played by optometrist in occupational environment encompasses.
Visual Acuity: Maximum visual acuity is desirable for every job but not always essential. The relative value of demands on acuity must be weighed in each job. Dynamic visual acuity is more reliable measure of a persons ability to perform tasks as driving or inspection tasks on a conveyer belt near, intermediate and distant.
Accommodation: Though it cannot be compromized in some occupations like few sports, in most of the occupations it can be managed with the appropriate type of occupational prescription.
Ocular Motility: Some jobs require wide fixational movements machinist, textile mechanism, sports and this may need to be done without moving the head. This indicates need for large frames and lenses, and vision training to combine movements of head and eyes.
Depth Perception: The visual system can effectively judge distance of objects using monocular and binocular cues. At low levels of illumination depth perception is of very low order which may be a problem for some occupations like photographs who have to cut photographic papers and chemical solutions in dark room . For drivers and pilots is very essential.
Peripheral Vision: Drivers, pilots, and sports field is required large lenses should be used with frames and lenses being close to face and angled in conformance to facial features.
Colour Discrimination: Under photopic conditions the human visual system has a highly developed colour sense. In certain work like transport drivers, interior decorations, painting and pilots, colour discrimination is important.
Individual Characteristics: Perfect occupational prescription even with proper type of multifocal segment for job needs can be a failure of the segment does not fit the individual characteristics. These include the subjects age, height, head posture, eye posture, head turning and eye movements. For example, taller the individual higher is the centre of his lens with respect to a fixed work level.
Factors influencing visibility of a task included:
The simplest of the factors is to adjust the level of illumination. Problems can arise due to insufficient as well as excess lighting at the work place. “Good lighting” is that which is adequate and sufficient for a given performance.
Contrast is differences in luminance between visual task area, background and environment and should not exceed certain maximum values. A relationship of 10:3:1 for normal task and 10:5:1 for precision tasks is recommended.
The concept of colour and colour contrast has been used in the industry to ascertain the moving parts and also to provide relief from fatigue.
Optometrists help in providing vision care services to a worker to make him visually efficient and visually alert. A perception for safety glasses should also fulfils employees visual requirements on the job. Vision care service in industrially advanced countries are being rendered in planned phases, its carried out in four steps.