Control of and protection from exposure to laser radiation

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Control of and protection from exposure to

laser radiation

This section recommends measures for the effective control of exposure to laser

radiation and protection from occupational exposure to optical radiation from laser

products. It applies to laser products which may consist of a single laser with or without

a separate power supply or may incorporate one or more lasers in an optical, electrical

or mechanical system. Such systems have been described in section 4.

7.1 Control measures – General concept

Approaches to laser safety vary greatly among individuals and groups who have

an interest in the problem. Most programmes in industry, government and universities

are still in the course of development. Some organizations have written policies and

practices outlining the responsibilities of management and of technical supervision,

environmental health, safety and medical personnel. Such policies are usually broadly

defined, with specific provisions for individual problems. All such policies and

procedures should emphasize the need to rely primarily on engineering controls.

Appropriate education and training should be conducted both for the individual laser

operator and for supervisory personnel for the safe conduct of laser operations.

Engineering measures should take into account the need for interlocks, proper layout of

room areas, shielding materials and warning signs. The criteria for selecting protective

eyewear involve many interrelated factors. It should be noted that commercially

available protective eyewear is designed for protection against a specific wavelength or

group of wavelengths. Eye protection devices designed for protection against specific

wavelengths and power from the laser system should be used when engineering and

procedural controls are inadequate. For cases in which long-term exposure to the eye by

visible lasers (only) is not intended, the applicable exposure limit may be based on a

0.25-second duration.

The International Electrotechnical Commission (IEC, 1984), the American

Conference of Governmental Industrial Hygienists (ACGIH, 1990) and the Laser

Institute of America (LIA, 1990) have prepared guides for laser installations, and the

American National Standards Institute (ANSI, 1986) and other national bodies have

developed a detailed personnel exposure standard for laser users. These documents give

hazard controls for laser radiation that vary depending on the type of laser being used

and the manner of its use. The control of laser operation should be entrusted to a

knowledgeable laser operator under the supervision of personnel knowledgeable in

laser hazards. A closed installation should be used when feasible.

In the above-mentioned guides and standards, only two general precautions are

common to all laser installations:

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