How to get free eclipse glasses and check for safety

Main points

• Thousands of libraries across the U.S. offer free eclipse glasses upon request—no membership required.
• The free glasses may lack bells and whistles, but they meet certified safety standards to protect your eyes during the eclipse.
• Look for ISO certification on the glasses and verify that they only show bright light to ensure they are safe for viewing.

If you plan to enjoy April’s total solar eclipse, whether you already live in its path, travel there, or plan to view a partial eclipse elsewhere, you’ll need protection. We’ve covered all the basics you need to know about the upcoming total solar eclipse and created a guide to help you find the best eclipse glasses you can buy online, but building your own pinhole viewer isn’t a safe bet The only way to watch the solar eclipse is for free.

Thousands of libraries across the United States are handing out free eclipse glasses, and all you have to do is ask a friendly librarian for a pair—no membership required.

Thousands of libraries across the United States are handing out free eclipse glasses, and all you have to do is ask a friendly librarian for a pair—no membership required. A free pair might not be as fancy as some of the options you can buy online, but with the total solar eclipse just days away, not having to deal with shipping is the best option anyway. But how good are free eclipse glasses, and how do you know if they’re safe? I grabbed a pair myself to check out.

Library freebies

The eclipse glasses my local library stocks are shipped flat and must be folded into shape before use. If you’ve ever worn red-blue 3D glasses (before the advent of 3D TVs and Vision Pro, one of the easiest ways to watch 3D movies at home), you’ll have a good idea of ​​how these eclipse glasses feel and work. The main difference is that they have dark gray metallic lenses instead of translucent red and blue lenses, and they’re completely opaque unless you’re looking directly into the sun.

My pair is branded with the National Science Foundation, a sun and moon on the outside, and orientation and safety certification information on the inside, but otherwise looks identical to the manufacturer, American Paper Optics The same as dozens of other eclipse glasses produced. Coincidentally, produces 3D glasses). More importantly, they fit easily over my glasses for my future eclipse viewing experiences.

The glasses aren’t the most comfortable option and certainly not the most durable, but they should be adequate for the three to four minutes I need to wear them. And I got them for free, so I can’t really complain that much.

How to know if your glasses are safe

It’s impossible to perform the necessary tests to determine whether a free pair of eclipse glasses actually protects your eyes from UV and infrared radiation at home, which means getting your glasses from a trustworthy source like a public library or museum. Particularly important. For both in-person and online purchases, the American Astronomical Society also maintains a list of trusted manufacturers, retailers, and dealers who allow them to certify eclipse glasses and viewer safety.

What safety information should you pay attention to on your glasses?

If you already have glasses, because maybe like me you got them for free, look for visual indicators as well. Safety solar eclipse glasses meet the requirements of ISO 12312-2, the standard developed by the International Organization for Standardization that governs safety glasses for daytime solar viewing.

Solar eclipse glasses or viewers that are safe to use will usually have an “ISO” logo or language indicating that they meet the requirements of the standard, such as “Meets and meets the transmission requirements for ISO 1231-2 optical filters for direct observation of the sun.” ,” which is printed on my free pair.

Now you can easily put your logo and text on any old glasses, so it shouldn’t be the only thing you check out. Another way to determine if the glasses you’re wearing are actually unsafe to use is to look at the lenses themselves.

The American Astronomical Society writes: “You should not be able to see anything through a safe solar filter except the Sun itself or relatively bright objects, such as the Sun reflected in a mirror, sunlight on shiny metal, or a hot incandescent filament. Light bulbs, bright halogen bulbs, bright white LED bulbs (including the flashlights found on smartphones), exposed compact fluorescent lamp (CFL) bulbs, or arc welding torches.”

Even if you can see these light sources, they should appear dim through the lenses of your eclipse glasses, not bright. If you can see the glow from something like a regular blackout desk lamp or a TV screen, and you don’t know who provided you with your glasses, it’s not safe to wear them. Likewise, if your glasses are translucent or clear under normal lighting conditions, they may not be safe to use.

Where to get free or cheap solar eclipse glasses

The STAR Library Network, an organization whose Solar Eclipse Campaign for Libraries (SEAL) program helps provide free eclipse glasses to your local library branch, has an interactive map you can check to learn about books in your local area Do the branch libraries have free glasses? If you’re not near a library, or if it’s out of stock, you can also buy inexpensive glasses from large retail chains like Wegmans, 7-Eleven, Lowes, Walmart, or Staples.

My local Lowe’s has cheap (less than $5) eclipse glasses for pickup today, and it’s easy to check online at other nearby retail chains to see if they also have purchase options. You still need to make sure the glasses you buy are safe to use, but if online shipping seems like it’s going to take a long time and your library doesn’t offer free glasses, this is a good option. There should always be a safe way to view a total solar eclipse, you just have to see what’s easiest to do where you live first.