Selecting the Proper Eyewear Lens
Every day eye injuries occur in workplaces across our industry. In nearly three out of five of these injuries, the injured person is either not wearing eye protection, or wearing eye protection that is inappropriate for the task.
Selecting protective eyewear to match the task greatly lowers the risk of injury. What may come as a surprise to some is how important a consideration for lens color can be. Some working conditions require a specific tint to reduce eyestrain. The wrong lens tint can result in eye fatigue that, at best, is an inconvenience and may have a negative impact on productivity, and at worst, can result in injury.
Eyestrain and the inconvenience associated with it is one of the chief reasons that workers remove protective eyewear. Naturally, this increases the chances for eye injuries. Keeping eyes safe depends not just on using eye protection, but also on using the correct eye protection.
The following definitions of common lenses should help you to match eye protection to the environment and the task.
Clear—the most commonly used lens. Clear polycarbonate lenses will absorb 99.9% of UV radiation up to 385 nm. They should be used in normal indoor light conditions.
Amber—actual lens color can vary from yellow to orange. They can be used indoors and should be considered for enhancing contrast for work in low light; a good example would be parts sorting where light levels are low and contrast is needed to reduce eyestrain. Amber lenses will absorb 99.9% UV radiation up to 400 nm but are not recommended for wear on in bright sunlight.
Standard Gray—these lenses are recommended for outdoor work where sunlight and glare can cause eyestrain and eye fatigue. Outdoor lens colors vary from brown, to gray to dark gray shades and will include mirrored lenses. Standard gray lenses absorb 99.9% of UV radiation up to 400 nm.
Indoor/Outdoor—the recently introduced 50/50, or indoor/outdoor lens shades tend to be clearer with a slight grayish tint, and can incorporate a slight mirror to the exterior of the lens. This type of lens shade should be considered for jobs such as shipping and receiving that require regular movement between inside and outside. These lenses do not work as sunglasses and should not be used for sustained outdoor tasks. They will reduce eyestrain from the glare of the sun, though not as effectively as standard gray lenses, but the convenience of not needing to change lenses or eyewear makes them an attractive option. UV protection is 99.9% up to 400nm.
Vermillion Lenses—distinguishable by their pink/red color, these lenses should be considered for enhancing contrast in inspection areas, or reducing eye fatigue and glare from fluorescent and halogen lighting.
Blue Lenses—lenses should be selected where work areas contribute high levels of yellow light, such as semiconductor facilities that use sodium vapor lighting.
Cobalt Lenses—these lenses provide infrared radiation protection, absorbing up to 70% of infrared from 780 nm to 2000 nm.
Proper eye protection can help to control specific impact hazards, reduce eyestrain and enhance productivity.