AUSTIN, Texas (KXAN) — On April 8, a total solar eclipse will dazzle millions in viewing distance of the natural phenomenon, which is set to be visible nearly all across North America. It marks the first one visible in the United States since Aug. 21, 2017.
Related video above: Can you safely take photos of an eclipse using your phone?
For those who witnessed the 2017 event, they might still have their old pair of solar eclipse glasses handy. But are those dated sets still safe to use?
During the total solar eclipse, viewers can only look directly at the sun during the brief totality phase, when the moon has entirely blocked out the sun’s face, according to the American Astronomical Society. Specific solar filter lenses are required for viewing the sun at any other point during the eclipse, AAS officials said.
Special-purpose solar filters must meet an ISO 12312-2 international standard to be considered safe to use. Manufacturers and distributors that meet that safety standard are listed here.
If your eclipse glasses meet that international safety standard and the filters aren’t scratched, torn, coming loose from the frame or damaged in any way, they’re able to be reused indefinitely. The AAS encouraged people to always check their solar filters for any damages prior to being used.
If a person typically wears glasses, AAS stressed the need to put the eclipse glasses over their traditional frames before viewing an eclipse. It isn’t ever advised to look at an uneclipsed or partially eclipsed sun through an unfiltered camera, telescope, binoculars or other device.
More information from the AAS on solar filter safety practices is available online.