Laser Safety Glasses: The Dangers of Consumer Lasers
The eye is the most vulnerable part of the human anatomy. It’s vulnerable to mechanical injury and to certain wavelengths of the electromagnetic spectrum. Prior to 1960, when the first laser was built, the damaging effect of artificial radiation such as welding flash, dropped off quickly as you moved away from the source. In addition, the normal visual spectrum of light didn’t pose a danger.
However, lasers have changed all of that — particularly with the more powerful lasers that can inflict injury across greater distances. The coherent light emitted by a laser means that even light in the normal visual spectrum can damage the eye when delivered with sufficient power.
The danger posed by lasers is exacerbated by its current widespread availability. Unlike the early 1960s when only researchers in well-funded laboratories used lasers, they are now commonly used by consumers for recreational purposes and by industry. This has led to many laser accidents that have injured a broad segment of the population, especially consumers. Here are two important laser risks to consumers:
Cheap Green Laser Pointers
The 5 mW green laser pointer is a class 3R device. Users should avoid direct eye exposure. However, the risk of eye injury is relatively small for people with a normal blink reflex. But this is only true of laser pointers made to spec. Laser pointers are widely available over the Internet from many sources, including ones of questionable reputation who may sell you dangerous green laser pointers.
Green lasers work by generating an infrared beam that is then converted into green laser light. During this process, some infrared laser light remains, which is blocked by an infrared filter. The manufacturers of cheap green laser pointers may cut corners in their design, manufacturing process, and materials used.
This may result in infrared filters that are poorly functioning or misaligned. Sometimes the filters are missing altogether, either by design or from poor manufacturing and quality control. The end result is a laser pointer that may emit ten times more laser light in the form of infrared. This puts it outside of its class 3R rating. In addition, infrared is invisible to the eye, so the user is unaware of eye exposure.
Handheld Laser Misuse
Handheld lasers are power rated from about 25 mW to 1000 mW. This makes them class 3B (avoid exposure to beam) and class 4 (avoid exposure to eyes or skin from direct or scattered radiation) devices. These more powerful lasers are readily available to the public via the Internet. The more powerful lasers can go as high as 3500 mW. These are capable of starting fires with many combustible materials. Because these are in the hands of consumers, their use is often casual. In fact, many people use them to do target practice on balloons.
The consumer’s creative uses of these dangerous devices can lead to tragic accidents. Targeting metallic, glass, or crystalline surfaces can scatter laser light back to the user’s eye. People have even injured their eyes by directing laser beams into mirrors. Many of these injury cases involve children and teens. Too often, these devices are used as if they were toys. However, any laser that can start a fire or pop balloons will instantly injure or even blind a person should it hit an eye.
Yet another problem with these high-powered handheld lasers is that they are sometimes advertised on the Internet as laser pointers. This mislabeling may cause people to use them as pointers in crowded lecture halls, which places everyone there at risk to accidental exposure. In addition, people won’t exercise care in their use because they believe them to be harmless.
When using handheld lasers, you should observe these safety suggestions:
- Use certified laser safety glasses. This includes yourself and others with you. Keep some spares for people who don’t have their own. When buying safety glasses, make sure they are meant for your specific type of laser. If you aren’t sure, get technical advice from a reputable seller. Getting it wrong can cause an eye injury or blindness.
- Use your laser like you would a gun. That means never aiming your laser at people, pets, or reflective surfaces. Even if a surface directs the beam away from you, it’s going in an uncontrolled direction. That is, it isn’t going in a direction deliberately chosen by you, and may injure another person.
- Store your laser in a safe place. Store your laser in a place that’s inaccessible to children. Remove the batteries and store in a separate place.
- Never look into a laser beam. If the laser doesn’t appear to work, don’t check it by pointing the laser at your eye. This kind of “testing” means that if the laser does indeed work, you learn this by injuring yourself. Note that some laser beams are invisible to the naked eye.
- Don’t allow your children to use your laser. Even supervised use is discouraged because the thrill of the experience will make them more likely to use the laser in your absence.
- Never look at a laser beam with an optical instrument. This includes binoculars, telescopes, microscopes, etc.
- Never use a laser on volatile substances such as gasoline or solvents.
Finally, don’t base a buying decision on how a seller labels a laser. Look at its technical specifications and description of its applications. For example, an ordinary laser pointer for lecturing or presentation purposes doesn’t require more than 1 to 5 mW of power. If it’s capable of burning holes through things, it’s the wrong device.
Follow the above safety tips, and don’t hesitate to contact us about your safety concerns and questions about getting the correct pair of laser safety glasses.