Due to the COVID-19 crisis, there’s an increased demand for sanitation methods that can be used with a wide range of items reliably and quickly. UV-C ultraviolet lights are a fast-germicidal technology that kills over 99% of biological hazards, eliminating viruses (including coronavirus), bacteria, mold, etc.
However, improperly UV-C use can be a danger to humans. Let’s review some questions and answers about this technology.
How is UV-C used?
UV-C lights are mounted in areas where the light shines on items or substances requiring germicidal treatment. The targets can be objects (such as beauty/nail salon tools, food containers, horticultural tools), or even flowing substances. For example, water can be purified by passing it through UV-C lighting. Robots equipped with UV-C lights disinfect public transportation, hospitals and other spaces.
Why is UV-C dangerous?
UV-C light is dangerous to people, animals and plants for the same reason it’s dangerous to coronavirus: It damages the DNA in cells to the point they can no longer function properly, leading to cell death. When a human’s skin, eyes, etc. are exposed to UV-C, cells in the area begin to die. This can not only interfere with the function of the affected area, it increases the risk of cancer, especially skin cancers.
Because UV-C is outside the visible spectrum, those may not use the simple natural defenses we have against damage to our eyes—closing them, shading them, blinking or squinting.
Unfortunately, a high-intensity UV-C source can cause damaging overexposure in just a few seconds.
What damage does UV-C cause?
Over-exposure can lead to eye and skin damage that can take 1-2 days or longer to appear. Exact effects depend on the wavelength and intensity of the light, proximity to the source, and time of exposure. Some UV germicidal devices produce ozone, and uncontrolled ozone buildup can create a hazard to the lungs.
Skin injuries range from minor to severe burns and are similar to a sunburn. Exposure usually doesn’t cause permanent major damage to the eyes, but victims can be effectively blind for two days or so. This is known as photokeratitis and is caused by burns on the cornea similar to those seen in snow blindness.
As we mentioned, UV-C exposure (especially exposure that causes skin damage) also increases an individual’s cancer risk.
How can we prevent these injuries?
Following these four procedures will greatly increase the safety of your workforce when it comes to UV-C.
- Increase awareness—Make sure your workers receive training on the dangers of UV-C and ways to prevent exposure.
- Avoid handheld units and any other unshielded equipment—A number of UV units coming onto the market to meet COVID-related demand lack necessary safety features. In particular, handheld units are potentially dangerous because they may lack proper shielding and can be easily pointed at skin or eyes. Avoid purchasing or using these or any other UV-C equipment that allows the light to be on while a worker might be exposed.
- Use equipment certified by an NRTL— No matter what you use, ensure it’s certified by Underwriter’s Laboratory (UL) or one of the other Nationally Recognized Testing Laboratories that certifies product safety. These products will include proper safety measures, whereas the growing number of products rushed to market use “safeguards” which leave plenty of room for accidental exposure.
- Employ protection measures—Even if UV-C equipment has an NRL certification, double-check to make sure it has proper safety measures that prevent radiation from being emitted while a worker is exposed. For example, a sanitation unit should have an interlock preventing it from being opened or serviced while the UV light is on, in the same way a microwave oven will not turn on while its door is open.
It’s also important to ensure workers who might be accidentally exposed to artificial UV light have proper PPE, such as UV-resistant gloves, goggles or face shields.
With the right training, safety measures, and certified equipment, you can use the sanitation power of UV-C while keeping your workers 100% safe.