Deep ultraviolet (UVC) light emitting diodes (LEDs) are an irradiation source and require due precautions to ensure safe usage. This page contains information intended to familiarize users with the current understanding of some of the general practices and precautions most often recommended in the literature for UV irradiation sources (further information is provided in thisapplication note). It is not meant as an exhaustive review on the topic. Currently, there are no work place related rules and regulations that are set by OSHA (Occupational Safety and Health Association) in regard to UVC environmental health and safety.
The UV spectrum is separated into four parts: UVA (315 nm to 400 nm), UVB (280 nm to 315 nm),UVC（200nm至280nm）和紫外线真空（100nm至200nm）。减小波长对应于较高的频率辐射和每个光子的较高的能量。
Biological Effect of UV Light
UVCradiation refers to wavelengths shorter than 280 nm. These wavelengths are entirely absorbed by our atmosphere and no natural UVC radiation reaches the surface of the earth. These wavelengths are available to us through artificial sources, such asUVC LED或汞灯。来自点源的强度，如UVC LED等1距离平方，并且一旦它超过散射长度，它会指数呈下降。这意味着1）从人的uvc源进一步，他暴露的少量剂量，2）人体皮肤中UVC辐射的吸收长度非常短，因此几乎没有UVC辐射可以达到活细胞皮肤;所有吸收发生在死区层中。
Learn about how a UVC LED works
“In any case, 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 readily detected (Campbell et al, 1993; Chadwick et al, 1995) which may explain why the dose response curve for UVC erythema in human skin is very much less steep than for UVB (Diffey and Farr, 1991). It is unlikely that UVC from artificial sources presents an acute or long-term hazard to human skin. However, UVC is likely to cause acute photokeratitis… UVC exposure is unlikely to cause acute or long-term damage to the skin but can cause severe acute damage to the eye and should not be permitted at all from any tanning device.”
同样的研究发现，有关人工光辐射产生的风险暴露的最低健康和安全要求（2006/25 / EC) - albeit for all UV bands combined: “Exposure limit value for UV (180-400nm) is 30 J/m2(= daily value of 8h)”
Acute (short-term) effects include redness or ulceration of the skin. At high levels of exposure, these burns can be serious. For chronic (long-term) exposures, there is also a cumulative risk, which depends on the amount of exposure during your lifetime. The long-term risk for large cumulative exposure includes premature aging of the skin and skin cancer.
- Prescription glasses and normal safety glasses do not protect eyes from UV exposure, so ANSI Z87 rated eyeglasses with wrap around lens to protect the side exposure is recommended. Consult with ANSI Z87 manufacturers for proper UV exposure protection equipment.
- Cover any exposed skin using lab coats, nitrile gloves or other lab attire.
短波紫外线照射可以降低through product safety design considerations and controls. For example, safety switches wired in series allow UVC sources to be turned off without exposing workers to UV light. Or placing ON/OFF switches for UVC light sources separate from general room lighting in locations only accessible by authorized persons. Switch locations should be locked or password protected to ensure that the UVC source is not accidentally turned on. Each UVC system should have the option of a viewport so workers can view the lamp assembly without the possibility of over-exposure to UVC.
Proper installation, monitoring, education of maintenance personnel, signage and use of safety switches can help to avoid overexposure. The operating instructions and recommendations for proper use of any UV system should be kept for reference to reduce hazardous exposure. These should be clearly visible for the operators or maintenance personnel and include the temperature and relative humidity ranges specified by the system design to ensure safe operation. Maintenance should be performed according to manufacturer’s instructions electric power should always be turned off to prevent accidental exposure. There are no standard guidelines for monitoring UV equipment, but there are commercial UV monitors that detect output or leakage.
- Follow your organization’s EHS incident reporting procedure. These often require documentation of the date and time of the incident, persons involved, equipment involved and type of injury.