Working outdoors – What should you consider when choosing safety glasses?
It is common knowledge that sunlight has an impact on the eye. While we wear sunglasses on a hot sunny day, or smoked ski goggles when on the trail, the same should apply when working outdoors.
Although it is not the first risk that comes to mind, ultraviolet (UV) rays that are not filtered by the atmosphere have an impact on the health of workers in the short and long term; ranging from eye fatigue and visual discomfort to premature eye aging and cataracts.
What kinds of hazards are your eyes exposed to when working outdoors?
Eye exposure to high intensity, visible light and solar radiation sources is a great risk when working outdoors, whether you are working in sunny or cloudy weather. This is because ozone and clouds do not block all solar radiation, including but not limited to ultraviolet. Ultraviolet, or UV, radiation is a type of energy produced by some man-made sources (such as welding equipment and lasers), but mostly by the sun. The sun emits three types of UV: UVA, UVB and UVC. The ozone layer absorbs all UVC and some UVB before it reaches us, but some UVB and all UVA pass through.
Some UV rays are good for us: they promote vitamin D production, boost the immune system and brain function, and maintain our circadian rhythms, which affects sleep and hormone production.
However, too much UV is harmful and can damage both our skin and our eyes, and it can happen in less than half an hour. As the average working day lasts about 8 hours, the use of appropriate protection against mechanical and radiological risks is mandatory in various sectors such as construction, mining, energy (including oil and gas) and farming.
The impact of solar radiation on the skin is now democratized and most people now use protective clothing, hats and sunscreen to protect the skin from UV damage, but sunglasses are still often considered secondary. And for those who wear sunglasses, they often neglect other occupational risks by using non-impact resistant products. Safety glasses that provide UV protection are more suitable when working outdoors.
What is the danger to the eyes specifically from UV radiation (sunlight)?
Various studies have been carried out over the years to classify the risks that UV rays can have on the eye organ, depending on the type of UV (according to the wavelength of the radiation) impacting the eye. All sources correlate overexposure to UV rays and eye damage, which may be temporary, lasting only a few days, or permanent, resulting in irreversible blindness.
These eye injuries can affect different parts of the eye, from the cornea to the lens or retina, leading to conjunctivitis, cataracts or even blindness.
How do reflections affect the eye?
Glare, caused by the reflection of sunlight off an extra-reflective surface like polished metal, water, or snow, will ultimately impact vision. Indeed, the reflections create sources of very high intensity luminosity, which are targeted towards the eyes. In addition to the information stated above, glare creates an additional risk of glare, which considerably reduces the comfort of vision and the perception of the depth of impact. This will have an impact on the ability of workers to understand the risks, thus increasing the risk of accidents at work. In order to reduce glare, certain lens technologies are available on safety glasses such as polarized lenses.
What should you look for when choosing safety glasses – both in terms of protection and wearing comfort?
When choosing safety glasses, consider both the frame and the lenses. Above all, the equipment must protect against the risks inherent in the task to be performed (chemical, mechanical, radiological, etc.). This can be identified by the mandatory markings on all EN166 safety glasses. Then, selecting the right lens will ensure the best visual comfort, and the frame will impact the fit of the product on the wearer’s face, and the wearer’s comfort. The best combination of lenses and frames is the model that wearers forget about when wearing it.
Although we’ll take a detailed look at the available lens options below, let’s focus on the frame.
The frame is a matter of fit:
Choose glasses that match your face shape and aren’t too big or too small. Models vary in size and some have multiple size options. There should be no uncomfortable pressure points in the nose, temples or behind the ears. The frame should stay in play as you move your head side to side and nod your head up and down. There should be no major obstructions to vision in any direction. Glasses should sit close to the face, but not so close that the eyelashes brush the lens or a large portion of the lens rests on the cheek.
Different types of frames:
- Half frame: These are popular because the frame is often lighter and better for longer wear and can allow for better peripheral downward vision. When choosing half frames, it is important to ensure that they fit properly without a large gap between the face and the lens
- Full frame: Full frame refers to “standard” eyewear that encloses the entire lens in the frame and ensures maximum lens security while looking closer to standard sunglasses.
- Sealed glasses: Sealed lenses sit between standard lenses and goggles, offering the comfort and clarity of goggles, but the protection from fine particles and spray offered by goggles.
- Protective glasses: The goggles offer maximum protection against dust, liquids and aerosols, providing a snug fit and full coverage. Different models of goggles have gaskets made from a range of materials depending on the risk involved.
Certain product features may improve the fit. To have optimal protection and adapt to the greatest number of types of faces, it is also necessary to take into account the curve of the frame, its size, but also the type of bridge of the nose and the flexibility, the thickness , materials and adjustability of the temples.
A major concern when wearing safety glasses is also lens fogging. The concern has only increased with the mandatory wearing of face masks in recent years. Indeed, working under the sun increases their body heat, causing perspiration and condensation on the lenses of the glasses. However, many permanent anti-fog coatings now exist from various suppliers, such as the PLATINUM anti-fog/anti-scratch coating from Bollé Safety. When working outdoors, always wear lenses with K&N markings, which provide the best protection against fogging and scratches.
Which standards are relevant for safety glasses when working outdoors?
The European standard for safety glasses suitable for outdoor use is EN172, which is part of the generic standard EN166. It is available on all types of glasses (glasses, goggles, face shields) and is recognizable on the product with a 5 or 6 as the first digit on the marking. This number is always followed by a second number to indicate the darkness of the product, ranging from 1.1 (for clear on photochromic products) to 4.1 (for extremely dark lenses). The most common markings on safety glasses for outdoor use are 5-2.5 and 5-3.1.
Which color is suitable for which applications?
There are different filters available for indoor and outdoor or outdoor environments.
In & Out lenses are for environments where workers often tend to move between low and high light workplaces. These lightly tinted or photochromic lenses provide the smoothest transition and provide eye protection without reducing visibility too much in indoor environments.
Exterior lenses represent the bulk of demand and offer a wide variety of tints and technologies. They include the regular smoked lens which was developed to act like a normal sunglasses lens. Smoked lenses protect the eyes from bright sunlight while blocking 99.9% of UV rays. This improves visual comfort and reduces eye strain. The shade can be dark gray or brown (depending on the wearer’s preference for visual comfort). A more advanced technology, Polarized, offers the advantage of smoked lenses while minimizing glare and improving visibility.
All exterior lenses can be flashed in different colors for aesthetic reasons and to reverberate heat.
Depending on the manufacturer, other lenses may exist and some lens tints may be available on prescription safety equipment.