The CHESS experimental area contains several kinds of lasers. The G3 station contains an excimer laser that operates in the ultra-violet region. This laser can operate at class IV (4) hazard levels, so be sure to follow the established standard operating procedures and safety precautions. If you are working with a laser that is running in a class IIIb (3B) or IV (4) mode (e.g. during initial alignment and testing), enclose the light path as much as possible and wear laser safety goggles (and skin covering if advised by the Laser Safety Officer). Additional lasers may be installed on a temporary basis in CHESS hutches for use during experiments. The use of these lasers is reviewed by the Laser Safety Officer
and is supervised by a member of the CHESS User Safety Subcommittee. Signage must be posted when these lasers are present. For use of class IIIb (3B) and IV (4) lasers, the hazard zone must be enclosed.
Appropriate laser safety goggles are available at the entrance to stations that house the lasers where their use is required. You must wear these goggles near any laser that has enough power to cause eye damage and whenever invisible laser light may be present.
Whenever a person may be exposed to either Class 3B (IIIb) or higher of laser light, the two-person rule must be observed. The second person in the hutch verifies that the first person uses reasonable procedures and does not make careless mistakes.
A list of people who have completed Laser Safety Training (and are therefore qualified to be the second person for the two-person rule) is kept in the CHESS Safety Committee Logbook.