The widely varying risk from class 3R laser products in light of the revision of IEC 60825-1 Available to Purchase

Laser products that emit continuous wave (cw) visible radiation with powers up to 5 mW have been widely used for pointing and alignment purposes for more than 30 years. Under IEC 60825-1 such lasers are classified as Class 3R. Experience shows that these lasers are quite safe for momentary accidental exposure, even though the exposure limit might be exceeded by up to a factor of 5. In this paper a case is made that this general experience of relative safety should not be extrapolated to pulsed emissions and extended sources without a more detailed quantitative risk analysis. Following the update of the exposure limits by ICNIRP, ANSI and IEC, the minimal safety factor of about 2.5 will apply to a much wider range of parameter combinations as compared to the current limits. For the case that Class 3R AEL values remain linked to the MPEs by a factor 5 in all cases, there will be many more products where an exposure can exceed the injury threshold even for momentary accidental exposure.