THE COHEN GROUP
  Environmental Health & Safety Consulting Services

The Cohen Group Newsletter - Volume 18  Issue 1, Article 5.  January 2007

UPDATE: LASER SAFETY IN CONSTRUCTION
By Julie V. Wellings, CIH

LASER is an acronym for Light Amplification by Stimulated Emission of Radiation. In simpler terms, laser light is non-ionizing radiation that consists of a single wavelength or narrow wavelength band and is emitted in a narrow beam. Lasers vary widely in configuration, wavelength and power, and therefore vary also in the potential hazards to users. Lasers are classified into safety classes numbered I (inherently safe) to IV (most dangerous, even scattered light can cause eye and/or skin damage).

In general, when focused on the eye, laser light of sufficient power can result in localized burning of tissue within in a matter of seconds. Some lasers can cause permanent damage to the eye with an exposure of less than one second. Lasers can also cause localized damage to exposed skin.

Certain infrared lasers with wavelengths beyond about 1.4 micrometers are often referred to as "eye-safe". However, the label "eye-safe" can be misleading as it applies only to relatively low power continuous wave beams. High power or "q-switched" laser light at these long wavelengths will burn the cornea of the eye and can cause severe eye damage.

Cal/OSHA standards for laser safety are found in the Construction Safety Orders (Title 8 CCR 1801, Non-Ionizing Radiation) and Tunnel Safety Orders (Title 8 CCR 8416, Lasers). The standards include (through text and reference) requirements for: (1) qualification of employees installing, adjusting or operating laser equipment, (2) use of personal protective devices, (3) posting of signs and labels, and (4) guiding the internal alignment of lasers. Both standards incorporate by reference the American National Standard Institute (ANSI) standards for laser warning signs and labels (ANSI Z136.1).

The California Occupational Safety and Health Standards Board (OSHSB) is proposing changes to bring the Cal/OSHA non-ionizing radiation and laser standards into compliance with current industry standards regarding warning signs and labels. Specifically, references to ANSI-Z136.1-1993 are replaced with references to ANSI Z136.1-2000. In addition, reference to Title 8 CCR 1516 (repealed in 2000) is replaced with reference to Title 8 CCR 3382, Eye and Face Protection. Finally, wording changes to Title 8 CCR 8416 are proposed for consistency with Title 8 CCR 1801. A public meeting and hearing will be held on February 15, 2007; additional information is available at www.dir.ca.gov/oshsb.