Anti-Fog Safety Glasses | The Ultimate Guide

There are several different technologies you can use to handle the issue of fogging of safety eyewear in the workplace, including anti-fog safety glasses.

Anti-Fog Safety Glasses | The Ultimate Guide

 anti-fog safety glasses


Whether you are looking for protective eyewear for day wear (with uv protection) or safety glasses for indoors with minimal lens tint, safety glasses can offer maximum safety in all settings.


Most safety glasses found on the market contain polycarbonate lenses, primarily because polycarbonate is a superior grade of plastic to others, for impact and temperature resistance. The other key benefit of polycarbonate is that they are all roughly 99% UV (ultraviolet) protected, which is important for general eye protection when working both indoors (lighting) and outdoors (sun).


Polycarbonate coating does have problems with scratching easily and fogging up (to be perfectly honest, all types of eyewear material have potential fogging issues). The majority of safety glasses come with a scratch-resistant coating applied to the lens, and this technology is fairly consistent between the various brands.


With that said, it has been a bigger problem addressing the fogging of safety glasses. In fact, there are different technologies used to handle this concern and there is no definitive answer to every fogging issue.


Why Do Safety Glasses Fog Up?

There are different scenarios that can cause a safety glass to fog up. To begin with, we need to realize that our eyeballs are warm, little, humidity generators. Your eyes give off moisture and when you have a safety glass that is close to your eyeball (causing lack of airflow), it could help generate some fogging concerns (partially depending on the temperature and humidity of the environment). 


A temperature difference between the inner and outer surface of the lens can cause them to sweat. If a worker is sweating and getting hot, it can exacerbate the problem. Safety professionals agree that a safety glass should fit snugly to the face with very little room for flying debris to enter around the lens. The idea of finding safety glasses that breathe well can be a challenging concern.


Quick temperature fluctuations are another concern when wearing safety glasses. Going from a hot to cold area (or vice versa) is the classic scenario for a lens to fog up. If you combine this with a dangerous work activity, like driving or operating certain machinery, it’s apparent that we need to figure out a way to address this. While that fogging might seem like an inconvenience, it could also be a real safety hazard.


Another more increasingly common reason for fogging lenses is due to wearing masks. Our hot, humid exhaled breath can rise directly up and under our safety glasses, causing a periodic fogging of the glasses synchronizing with our breath.


In summary, lens fogging is caused by water vapor condensation that lands on the cooler surface of your lens. The vapor cools and turns into tiny drops of liquid on the lens, giving it that film you see as fog.


Fixing the Problem

Lens Coatings

Without a doubt, purchasing coated anti-fog safety glasses is the smartest and easiest way to address this concern. There are two types of coatings:


·         Hydrophobic means “water-fearing”. This type of coating repels water, causing it to run off the lens. It is best for high moisture environments and those where workers are regularly transitioning between environments with varying temperatures. This is the most common coating used on anti-fog safety glasses when the technology was first invented back in the 1960s.

·         Hydrophilic means “water-loving”. With this type of coating, water is absorbed by the coating. Anti-fog safety glasses featuring this coating are best for moderate moisture environments.


Both coating types can adequately serve various anti-fog needs and some brands utilize both technologies in their coated lenses.


Understandably, anti-fog coatings can wear out over time as your anti-fog safety glasses are cleaned. In fact, some manufacturers recommend very specific cleaning solutions for use on their anti-fog safety glasses.


Anti-Fog Sprays/Agents

Another idea to consider is the use of anti-fog sprays, gels and other agents. Some of these sprays are a combination cleaner and anti-fog additive, while other anti-fog drops/sprays on the market are only meant to be put on a clean lens. Results will vary based on a number of variables, so experimentation is always advised. There are numerous tests/reviews you will find online that have been conducted but it is challenging to nail down one product brand that works well in every situation.


Styles of Safety Glass with Better Ventilation

As ventilation increases around the inside of anti-fog safety glasses, there should be fewer fogging concerns during certain work scenarios and conditions. As mentioned earlier, safety glasses are meant to block flying debris from entering the eye area, so we do not want too many gaps between the face and the safety glass. Part of this decision is looking at the work environment and the risk of small flying debris coming around the safety glass.


Some manufacturers design some of their safety glasses to indirectly vent and breathe. Simply investigating and trying different styles of anti-fog safety glasses could help with adding better ventilation around that glass.


ANSI Standard for Anti-Fog Safety Glasses

In 2020, the International Safety Equipment Association (ISEA) revised a US standard (ANSI Z87.1-2020, which is a part of the eyewear standard ANSI Z87.1) for anti-fog safety glasses. The standard mandates that eyewear can only be classified and marked as anti-fog if lenses remain fog-free for at least eight seconds. Manufacturers would go through a special documented test and, if approved, would be designated with an “X” on the lens.



As we know, the human head come in all shapes and sizes and we need a good selection of anti-fog eyewear to accomplish several goals for the employee:


·         Be comfortable to the worker so they will continue to wear these safety glasses

·         Be well-fitted to ensure appropriate protection based on the work environment

·         Select coated lenses that prevent fogging based on the work environment


Trying to investigate and understand why safety glasses are fogging is important to think about. More often than not, you are faced with a trial-and-error approach to solve your fogging issue. Our Safety Services Team can help review your particular situation and recommend several styles of anti-fog safety glasses, if you have struggled with this fogging problem.


Conney Safety carries a wide selection of safety glasses. Check out our full list of anti-fog safety glasses here



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