Laser Safety-Environmental Health & Safety - Carnegie Mellon University

Laser Safety

There are a great many lasers and laser-containing devices present at Carnegie Mellon University. Our Laser Safety Program comprises several different activities:

Laser Inventory Registration

For all areas containing lasers, the PI, lead researcher, or supervisor is responsible for providing EH&S with an up-to-date inventory of those lasers. This information must include the manufacturer, model and serial number of the unit, along with its location, laser classification, wavelength(s) of radiation, power, pulse details (for pulsed lasers), the laser medium, beam divergence, and the intended application for the unit.  Researchers who have already submitted a registration form do not need to re-submit this document unless they wish to modify their inventory.  Please send completed forms to Andrew Lawson (LSO).

Medical Monitoring

Users of Class 3b and 4 laser systems should be offered initial medical evaluations prior to their laser use. EH&S has arranged with a contracting medical center to perform these evaluations. Contact EH&S at (412) 268-8182 for further detail.


All laser users should attend the EH&S Laser Safety Training class; it is MANDATORY for users of Class 3b and Class 4 lasers. Check the EH&S training page for further information.

Protecting Yourself from Laser Overexposure

A wide variety of control measures are possible for the safe operation of laser equipment. A key element in this process is the need to maintain radiation levels below the Maximum Permissible Exposure (MPE) as outlined in ANSI Z136.4. Examples of these controls are protective eyewear, beam stops, protective interlocks, limited beam paths, controlled areas and protective housings. If you are unsure of the status of your laser equipment with regard to maintaining exposures below the MPE, contact EH&S at (412) 268-8182.

Warning Signs and Labels

A thorough system of warning signs and labels is in place to provide suitable awareness of laser hazards. This system warns persons of the presence not only of hazardous radiation, but also of related fire, chemical and electrical hazards.  DO NOT remove any hazard identification labels from a laser system.

Documentation of Laser Use

Documentation of laser use is a critical element of working with lasers.  The EH&S “LASER Use Authorization Form” must be completed by researchers who plan to use Class 3B and Class 4 Lasers for their research.  This application contains information regarding the type of laser(s), the proposed use, the identification of possible hazards, and how these hazards will be controlled.  Additionally, SOP's must be developed and posted for Class 3B and Class 4 Laser use.  Please contact Andrew Lawson at for more information.