NIST Tests Find Few Green Lasers Meet Federal Regulations
Laura Ost reports nearly 90 percent of the 122 tested green hand-held lasers and 44 percent of red ones were out of compliance.
Tests of hand-held green and red laser pointers by National Institute of Standards and Technology (NIST) researchers showed nearly 90 percent of the 122 tested green lasers and 44 percent of red ones were out of compliance with current federal regulations -- that is, they were more powerful than the legal limit.
The tests involved a low-cost apparatus designed to measure the properties of hand-held laser devices; the apparatus provides quick results and can be replicated easily by other organizations, Laura Ost reported March 20 for NIST's Tech Beat. She said the test researchers reported their test results that day at a conference.
"Green pointers often emitted unacceptable levels of infrared light as well," Ost wrote. "Anecdotal reports of green laser hazards have previously appeared in scientific journals and the media, but the new NIST tests are the first reported precision measurements of a large number of hand-held laser devices. The NIST tests point out that many red laser pointers are also -- unexpectedly -- out of compliance with federal regulations."
The tests conducted by NIST Laser Safety Officer Joshua Hadler and a colleague involved randomly selected, commercial laser devices labeled as Class IIIa or 3R and sold as suitable for use in classrooms and other public spaces. Regulations limit such lasers to 5 milliwatts maximum emission in the visible portion of the spectrum and less than 2 milliwatts in the infrared portion of the spectrum, but about half the devices had power levels at least twice the limit at one or more wavelengths, according to Ost's report. "The highest measured power output was 66.5 milliwatts, more than 10 times the legal limit. The power measurements were accurate to within 5 percent," she wrote. "According to the American National Standards Institute (ANSI), laser devices that exceed 3R limits may be hazardous and should be subject to more rigorous controls such as training, to prevent injury."