Special Requirements for Invisible Laser Beams
This section has been reviewed and updated as needed: April 2014
Since infrared (IR) and ultraviolet (UV) wavelengths are normally invisible to human eyes, they possess a higher hazard potential than visible light lasers. Therefore, the use of laser eyewear that will protect against the exposure is required at all times during laser operations.
- The collimated beam from a Class 3 laser should be terminated by a highly absorbent backstop wherever practicable. Many surfaces which appear dull visually can act as reflectors of IR.
- A class 4 laser beam should be terminated in a fire resistant material whenever practicable. Periodic inspection of the absorbent material is required since many materials degrade with use.
- Exposure to UV should be minimized by using shield material that attenuates the radiation to levels below the appropriate MPE for the specific wavelength.
- UV radiation causes photochemical reaction in the eyes and the skin, as well as in materials that are found in laboratories. The latter may cause hazardous by-products such as ozone and skin sensitizing agents. The use of long-sleeved coats, gloves, and face protectors is recommended.