Product Code: JLA_7_1_62

Authors:
Arthur G. Varanelli
Raytheon Co., 141 Spring St., Lexington, MA 02173, U.S.A.

The range and degree of electrical hazards associated with lasers is generally greater than encountered with other forms of equipment in the industrial, commercial, or scientific sectors. In laser equipment the electrical energy conversion to ‘optical’ wavelength energy is achieved by many methods, each method having differing electrical safety hazard exposures. Laser output is described in terms of beam power, energy, wavelength, and spatial characteristics, enabling common points of comparison and beam hazard characterization. In contrast, the methods of electrical energy conversion have unique characteristics which are not generally appreciated. It is natural to expect this, as it is the laser beam that is the instrument of useful work, not the manner in which the beam is produced. The fact that certain energy conversion methods require electrical equipment having more in common with radar transmitters leaves open the problem of severe electrical hazards through unfamiliarity and inexperience. Many severe electric shock accidents with laser power‐supply and pulse‐forming equipment have occurred for these reasons. Several common electrical energy conversion systems and their general electrical safety requirements are discussed and connections to the requirements and expectations of current codes and regulations are explored. An understanding of the triad of equipment exposures, equipment environment, and the human element is developed to provide a greater appreciation of the necessity for recognition, evaluation, and control if electric shock accidents are to be avoided.