Here’s How to Tell if You Have a Pair of Fake Solar Eclipse Glasses

The American Astronomical Society said the glasses should “block all” of the “sun’s ultraviolet light” except for a “fraction” of it

Experts are warning people to make sure they have the right pair of glasses to watch the total solar eclipse happening on April 8.

The American Astronomical Society (AAS) said in a March 22 release that it found “counterfeit and fake” glasses to view the eclipse were “polluting the marketplace” in recent weeks ahead of the eclipse — and warned people to make sure their glasses are safe to use.

“With millions of North Americans only now becoming aware that a solar eclipse is imminent and seeking to get their hands on eye protection, it is critical that everyone understand how to spot unsafe products,” the AAS said.

The AAS explained that solar eclipse glasses that are protective “block all” of the “sun’s ultraviolet (UV), visible and infrared (IR) light” except for a “fraction” of it. It noted that because counterfeit glasses do not do this, people using them to view the eclipse may experience “severe” eye injuries ranging from “temporarily impaired vision” to “permanent blindness.”

Related: All About the Rare Total Solar Eclipse, Including Where It Occurs and How to See It

“Filters that provide safe, comfortable views of the sun generally transmit between 1 part in 100,000 (0.001%) and 1 part in 2,000,000 (0.00005%) of its visible light,” Rick Fienberg, project manager of the AAS Solar Eclipse Task Force, said in the release. “Solar filters are at least 1,000 times darker than even the darkest regular sunglasses.”

The AAS showed an example of counterfeit glasses versus real ones and noted that the lenses of the fake ones were "black and have straight left and right edges," while the lenses of the real ones were "reflective" and had "curved left and right edges."

Fienberg said people can test if they have real solar eclipse glasses by trying them on indoors prior to the eclipse. He said if they are real, people would not be able to “see anything through them,” except maybe “very bright lights,” but these would be “faint.”

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He said if the glasses pass this first test, then people can also test the glasses outdoors. Again, they shouldn’t be able to see anything, except for the sun’s glare off a surface, which should also be faint.

The third test is glancing at the sun for “less than a second.” He said people should only see “a sharp-edged, round disk” that is “comfortably bright.” He said the color of the sun is dependent on the filter in the glasses so it can appear “white, bluish white, yellow or orange.”

Related: Where to Buy Solar Eclipse Glasses? All About the Specialized Glasses Recommended by NASA

Fienberg said if the glasses pass all three tests they “should” be safe, but he recommended that if people are still unsure, they should use the glasses “sparingly” and only look through them “for no more than 2 or 3 seconds every 5 minutes.”

The AAS said that knockoffs can copy a statement that the glasses comply with the ISO 12312-2 standard for filters to observe the sun and can even have the same names as reputable companies printed on them. The only way to make sure they work properly is to test them, which can only be done in a lab.

However, the AAS Solar Eclipse Task Force said it has tested products and released a list of vendors of safe solar viewers that it is sure follow the standards for solar eclipse safe viewing.

“We recommend not buying eclipse glasses from random sellers in online marketplaces, even if they claim to get their products from a supplier on our list or to be approved by the AAS or NASA,” the AAS said.

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