By Anita Oh

PHILADELPHIA (CBS) — As eclipse enthusiasts gear up for the Monday moment when the moon fully blocks the sun, some are discovering their eclipse glasses could be unsafe.

“I was needless to say very, very upset,” said Carol Parsons, director of Tinicum Public Memorial Library.

Parsons purchased 30 pairs of solar eclipse glasses online in order to hand out free-of-charge to library patrons.

“We’re just here to serve the community in a safe way,” she said.

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Earlier this week, the company refunded her purchase, saying the lenses from a third-party vendor do not meet safety standards for viewing the solar eclipse and could cause eye damage to those wearing them while looking at the sun. Similar faulty glasses have been recalled elsewhere by Amazon and other vendors.

An added layer of confusion: some of these solar eclipse glasses are marked as if they meet NASA safety requirements but they don’t.

“I think that’s terrible because you can actually go blind watching the solar eclipse,” said James McMahan, who stopped by the library Friday to try and pick up a pair of glasses.

“Although we’re only talking about 30 pair of glasses, those are still 30 sets of eyes that are important to us,” said Parsons.

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She urges buyers to check the list of recommended manufacturers and authorized dealers compiled by the American Astrological Society, a resource she says she wishes she checked before buying these Abco Tech glasses.

“No, they were not on that list,” Parsons said.

Parsons and her team immediately reached out to patrons who took the glasses and have recovered the majority.

But, overall, this small hiccup isn’t darkening any enthusiasm for those looking forward to seeing the eclipse.

“It don’t happen very often and this would be my third one that I’ve been able to see,” said McMahan.

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