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Writer's pictureChris Rivera

Laser Safety Today



Laser injuries, especially among children are thankfully rare. Unfortunately, with access to more powerful and affordable lasers through online marketplaces, they are becoming less so. Poor regulation and lack of educational resources could quickly turn your child’s fascination with lasers into a trip to your optometrist and/or ophthalmologist. Lasers are powerful tools and come in many shapes and sizes. Laser light can be both visible and invisible, sometimes simultaneously! If you are interested in a laser product, it is important to know what kind of laser you are purchasing, as well as making sure the laser really adheres to specifications presented online or on the labeling. This blog highlights some basic safety information and terminology, but if in doubt, it is better to avoid lasers as toys and encourage kids to respect these powerful scientific instruments.





A laser experiment being conducted at the Air Force Research Lab




Laser Types

The most common types of lasers on the market consist of red and green laser pointers. While some red lasers are truly emitting red light, typically from helium-neon gas, it is more common to use an infrared laser (IR) which is converted to other visible wavelengths of light. Although IR is outside of our visible spectrum, it can still be absorbed by lens and retinal tissue, causing both acute and long-term damage. Although your laser might appear to emit only visible light, without proper filtering, IR can sneak though at even higher levels than what is listed for the intended visible emission wavelength.




Diagram of the electromagnetic spectral scale.


At a minimum, it is important to only buy lasers from reputable sources, and it is a good idea to ask manufacturers about the type of laser and all wavelengths of laser light emission. Make sure to ask about laser power, wavelength and divergence (how tightly the beam is focused). For more information on basic laser pointer properties:



Laser Classification


The FDA has classified lasers into 4 general classes. In general, class I lasers are considered non-hazardous, but if viewed through a lens, like in binoculars or a magnifying glass, can still pose a threat to vision. Note that laser pointers are considered class IIIa and are considered dangerous when viewed directly with an unaided eye.




FDA laser classification table.


All class IIIb and IV lasers are considered dangerous, even through skin contact only. While class IIIb and IV lasers are generally used only in professional settings, it is still possible to purchase these types of lasers without restriction though both new and second-hand marketplaces. It is also possible to purchase a laser that is mislabeled or damaged in a way to make it more dangerous than expected. As always, when in doubt, don’t purchase any laser without knowing the classification and risks.





Image of a class IV IR laser cutting tool



Laser Eye Injuries


Laser damage in eyes is a result of the intense radiation being absorbed by different parts of the ocular system. Injuries to the lens, retina or other surrounding tissues can be either temporary or permanent. Light emitted in the visible region (400 – 780nm) is easily absorbed by the retina and will cause a retinal burn. While this is likely the most common injury due to the proliferation of visible laser pointers, our natural glare-aversion or “blink” response will usually limit damage (no laser staring contests!).




Retinal burn damage in a child’s eye from a laser pointer injury.



With deep ultra-violet (UV <400nm) and IR (>780nm) lasers, we don’t have a natural blink response, so we are more prone to exposure damage. As someone who works with industrial and military grade lasers for a living, I am very familiar with class IV laser radiation, and take laser safety very seriously. In my workplace, laser safety goggles are inspected and always worn when operating hazardous laser systems. Even with the most careful safety precautions accidents can happen. While at a previous employer, I was injured by a class IV IR laser and temporarily lost vision in one eye. While my vision fully recovered, I have a permanent laser burn that can be identified at my regular optometrist visits. It is a permanent reminder of the power of laser light and the effects they can have on our eye health.


If you, or anyone you know, has been exposed to a laser and are experiencing vision issues, please visit an optometrist or ophthalmologist as soon as possible. If exposure results in pain, bleeding, vision loss or a popping sound, please seek emergency medical help immediately. As lasers become more prominent in our day-to-day lives, so do the risks. Keep your eyes safe and visit your optometrist yearly!


If you, or your children are interested in lasers, there are many fun educational tools and videos available. Please encourage your children to remain curious but stress the importance of respect when it comes to these powerful tools. Find more resources in the links below:





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