The risks may include:
• Mechanical hazards (solid particles, dust, chips, etc.)
• Optical hazards (ultra-violet and infra-red)
• Chemical hazards (liquids and gases)
• Thermal hazards (a high level of heat radiation and contact heat)
• Ergonomic hazards (bad posture, incorrect strength)
The eye is vulnerable, a small speck of dust in the eye can cause much irritation and discomfort.
The human eye is made up of:
The cornea is the transparent part on the outside of the eye. This is in direct contact with the outside world and is very sensitive. Through the cornea light enters the eye.
This is the black dot in the centre of the eye. The coloured area around the pupil is the iris. The pupil gets smaller as more light enters the eye, and larger if there is less light.
The lens is located behind the iris. The lens is Biconvex (at the sides of the sphere) and may deform. By stimulation of the muscles around the lens, the lens becomes rounder allowing the eye focus on objects which are close. Relax the muscles and the lens will become flat again. Therefore objects from afar can still be viewed sharply. As a person gets older (usually between 40 and 50) the lens is less elastic. Therefore the accommodation capacity will slowly go backwards. That is the moment when reading glasses and/or monitor glasses are needed.
In old age many people experience clouding of the lens. This is also known as cataract. The lens may also lose transparency (cataract). This may result from exposure to IR (infra-red light) and UV (ultraviolet light). This may result in loss in sharpness of sight.
The retina is located at the rear of the eye. It is also here that the light rays which come through the lens get bundled together. The information is sent to the brain by the optical nerve and as a result we become aware of the image. Burned retina cells lead to irreversible vision loss.
European Standards Eye Protection.
NEN-EN - 165 Terms and definitions
NEN-EN - 166 General specifications, such as design, classification, minimum requirements, specific optional requirements, mark, instructions for use
NEN-EN - 167 Description of all optical test methods
NEN-EN - 168 Description of all non-optical methods
NEN-EN - 169 Filters for welding and related techniques: transmittance requirements and recommended use
NEN-EN - 170 Ultraviolet Filters: transmittance requirements and recommended use
NEN-EN - 171 Infra-red filters: transmittance requirements and recommended use
NEN-EN - 172 Sunlight filters for industrial use
NEN-EN - 175 Resources for eye and face protection during welding and related processes
NEN-EN - 207 Filters for eye protection from laser radiation
NEN-EN - 1731 Eye and face protection of woven wire
NPR-CR - 13464 gives guidance for the selection, use and maintenance of professional eye and face protection