Is UVC Safe?

Is UVC Safe?

Deep ultraviolet (UVC) light emitting diodes (LEDs) are sources of radiation and need to be used safely. The information on this page is meant to acquaint users with the state of knowledge regarding some of the general precautions and practices frequently advised in the literature on UV irradiation sources (further details are provided in this application note). It is not intended to provide a thorough analysis of the subject.

In terms of UVC environmental health and safety, there aren't any workplace-related norms and regulations currently established by the Occupational Safety and Health Association (OSHA).

UV Light's Effects on Health

From 10 nm to 400 nm is the UV region of the electromagnetic energy spectrum. UV radiation can injure the skin and eyes depending on the wavelength and length of exposure.

Four sections make up the UV spectrum:

UVA (315 to 400 nanometers)
UVB (280 to 315 nanometers)
UVC (200–280 nanometers)
UV Vacuum (between 100 and 200 nm)

Higher frequency radiation and more energy per photon are associated with wavelength reduction.

UV light's effects on living things

Even though UVB radiation is well known for its damaging effects on human skin and ties to skin cancer, each of the UV bands—UVA, UVB, and UVC—presents unique risks to people.

UVC radiation is defined as having wavelengths under 280 nm. Our atmosphere completely absorbs these wavelengths, therefore no natural UVC radiation reaches the earth's surface. These wavelengths are accessible from man-made sources like UVC LEDs.

Once it has passed the scattering length, the intensity from point sources like UVC LEDs decreases exponentially. It decreases as 1 over the square of the distance. This means that 1) the amount of UVC radiation a person receives depends on how close the source is to him, and 2) because of the human skin's exceptionally short absorption length, very little UVC radiation can reach the skin's living cells. Instead, all of the absorption takes place in the dead cell layers.

Rarely, prolonged direct exposure to UVC radiation can cause temporary eye and skin damage, such as corneal injury (also known as "welder's eye"), though these conditions usually resolve on their own within a few days. Therefore, protecting skin (especially open wounds) and, most crucially, the eyes from UVC radiation is advised when using UVC LEDs.

You can find here the safety recommendations for using UVC sources from the EU health agency. The study finds in particular that:

However, UVC is strongly attenuated by chromophores in the upper epidermis (Young, 1997) and UVC-induced DNA damage in the dividing basal layer of human epidermis is not easily detected (Campbell et al, 1993; Chadwick et al, 1995), which may explain why the dose response curve for UVC erythema in human skin is much less steep than for UVB (Diffey and Farr, 1991). UVC from artificial sources is unlikely to pose a short-term or long-term risk to human skin. But UVC is probably going to result in acute photokeratitis... UVC exposure from any tanning device should never be allowed because it is unlikely to cause acute or long-term damage to the skin but can cause serious acute damage to the eyes.

The same study discovered the minimum health and safety regulations (2006/25/EC) for employees' exposure to dangers from artificial optical radiation, albeit for all UV bands combined: "Exposure limit value for UV (180-400nm) is 30 J/m2 (= daily value of 8h)"

Skin Effect of UVC

Acute (short-term) impacts might cause the skin to become red or to ulcerate. These burns might be severe if there has been a lot of exposure. There is also a cumulative risk for chronic (long-term) exposures, which is based on the total lifetime exposure. Large cumulative exposure poses a long-term danger for skin cancer and early aging of the skin.

UV radiation from Personal Protective Equipment (PPE) is easily absorbed by materials including clothes, plastic, and glass. UV radiation is no longer active once it has been absorbed. In order to protect all exposed areas while working with open UV radiation during maintenance, servicing, or other circumstances, personal protective equipment is advised. Working near UVC equipment requires that one:

Use full-face or UV-blocking masks.

It is advised to wear safety glasses with a wrap-around lens to prevent from side exposure since prescription glasses and regular safety glasses do not shield the eyes from UV radiation.

Use lab coats, nitrile gloves, or other lab clothing to cover any exposed skin.

Design, Control, Monitoring, and Maintenance of Safety

Through product safety design considerations and controls, UVC exposure can be decreased. For instance, safety switches wired in series enable the turn-off of UVC sources without exposing personnel to UV light. Alternatively, place ON/OFF switches for UVC light sources in locations that are only accessible to authorized individuals. To prevent the UVC source from being unintentionally turned on, switch locations should be locked or password-protected. A viewport should be an option for every UVC system so that personnel can inspect the lamp assembly without the risk of excessive UVC exposure.

Overexposure can be prevented with the help of proper installation, monitoring, training for maintenance staff, signage, and the use of safety switches. To minimize risky exposure, it is advisable to keep the UV system's operating manual and suggestions for correct use on hand. The temperature and relative humidity ranges specified by the system design should be included in these for the operators or maintenance staff to see clearly in order to ensure safe operation. Electricity should always be turned off to prevent unintentional exposure. Maintenance should be carried out in accordance with the manufacturer's instructions. While there are commercial UV monitors that may detect output or leakage, there are no set standards for monitoring UV equipment.

Adaptation to UV Exposure

The effects of acute UV radiation exposure are often mild, and many symptoms take time to manifest. The following steps are advised in case of UV exposure:

Consult an ophthalmologist if you suspect eye damage.

Skin lesions as soon as possible

Observe the EHS incident reporting process for your company. These frequently need for documenting of the incident's date and time, participants, equipment, and injury kind.
 

280nm UV Light Tube

Features:

● Surface mount high-power device
● Featuring high brightness combined with a compact size
● Suitable for all kinds of lighting applications such as general illumination, flash,spot, signal,industral and commercial lighting.

Specification: