Are old eclipse-watching glasses OK to use to protect your eyes during the big event coming April 8?
Maybe, with several important ifs.
They are likely safe to use if:
- there are no holes or deep scratches in the lenses or damage to the frames that would keep them from securely covering your eyes;
- they are stamped with an ISO number (occasionally seen as ISO-12312-2 or ISO-12312-2:2015);
- they were made no earlier than 2015.
READ: Your guide to April's solar eclipse in Lancaster County
That date is a key because the most recent safety standards were mandated, said Dr. Phil Schwartz of the Eye Center of Lancaster County in an email.
Damage is another concern, Schwartz pointed out.
However, “as long as they are without damage,you can still use them,” said Mark Margolis, owner and founder of Los Angeles-based company Rainbow Symphony, which has been manufacturing solar eclipse glasses for over four decades. “The truth is, it's more of a marketing thing. We tell people, if you stored your glasses well, you're fine. If there's separation from the frame, maybe consider getting new ones.”
Rainbow Symphony, one of few North American manufacturers of solar eclipse glasses, creates its glasses with a mixture of different polymers and a metallized coating that makes damaging them difficult. Margolis said that the company plans to sell millions of pairs of glasses to meet the need of people living and traveling in the April 8 eclipse’s path of totality, stretching from Mexico to Canada and across the United States.
What’s the best way for checking the glasses lens for damage? Presenter and Astronomers Enthusiasts of Lancaster County member Tom Lugar addressed this question at a recent club meeting,
“Just take your glasses and hold them up – as long as there are no holes or light coming through, they’re OK,” said Lugar.
Safety is the name of the game with solar eclipse glasses, as even a few seconds of unimpeded viewing of a solar eclipse with the naked eye is enough to burn the retina. Additionally, older glasses occasionally come with a warning that says to not look through the glasses for more than three minutes at a time, but in most cases, these are attached to glasses created before the ISO standard was introduced in 2015.
In Lancaster County, the eclipse will run from 2:06 p.m. to 4:34 p.m. and reach its height at 3:22 p.m. with 91.7% of the sun covered by the moon. The sun will not be completely covered because Lancaster County is not in the path of totality, the zone where the moon will completely cover the sun. That will happen in parts of just four of Pennsylvania’s 67 counties – Erie, Crawford, Mercer and Warren.
