Tinted eyewear lenses

Responding is Katie Aune, application engineer, 3M Co., St. Paul, MN.

Selecting the appropriate lens tint for your organization’s protective eyewear is important to help ensure worker health, safety, comfort and even productivity. Lens tints serve different purposes, and understanding these can help you make a more informed decision.

Every light source has its own range of wavelengths in a spectrum. Knowing this range for a given light source is the easiest way to make sure the selected lens tint gives your workers the protection they need. Distributors and manufacturers can help match the spectrum with the most suitable lens tint option. There are instances when the spectrum is unknown, so generalized tint benefits should be considered.

Clear lenses are the most popular choice because of the high visible light transmittance, or VLT, of around 90%. This means that about 90% of the light comes through the lens and reaches the eye, making clear lenses ideal for well-lit environments and the widest variety of applications.

Amber lenses (VLT of approximately 90%) are ideal for overcast or foggy conditions during the daytime. They enhance contrast and visual acuity, making them good for tasks requiring detailed inspections. These tints aren’t recommended for night driving, as they can reduce the total available light reaching the eye. These lenses also protect against blue light emitted from screens and LEDs, making them useful in office settings.

If you find an amber lens changes the color perception in your environment too much, brown or light-brown lenses (VLTs of approximately 25% and 70%, respectively) are another option for enhancing contrast and visual acuity with some protection from blue light.

Indoor/outdoor gray lenses have a VLT of approximately 68% and are designed with a gray tint light enough for indoor use and dark enough for outdoor conditions. They reduce how much the eyes need to adjust when moving between different lighting conditions, making them suitable for workers frequently transitioning between indoor and outdoor environments.

Gray lenses are best for outdoor applications where light and glare can cause eyestrain and fatigue. A gray tint (VLT of approximately 15%) provides good protection from glare and helps keep color distortion to a minimum.

Light-blue lenses reduce brightness and glare, particularly in indoor areas with fluorescent lighting. With a VLT of approximately 80%, light still gets through, making them ideal for tasks that involve detailed inspections. In the food industry, light-blue lenses provide better visibility in preparation and processing areas.

Outside of tints, there are also a couple options to consider. Mirrored lenses reduce brightness and glare by reflecting light off the lens and not allowing it to pass through. A polycarbonate lens naturally absorbs around 99% of UVA, UVB and UVC light in the 200-380 nanometers range, offering ultraviolet protection even with clear lenses.

Selecting the right tinted protective eyewear protects your eyes from more than task or lighting hazards. It can help protect against eye fatigue, eyestrain, light sensitivities and headaches, resulting in fewer instances of workers removing their eyewear because of discomfort and consequentially exposing their eyes to potential hazards or impacting productivity.

Editor's note: This article represents the independent views of the author and should not be considered a National Safety Council endorsement.