(NEXSTAR) – Astronomers, optometrists and even the U.S. government have been warning us for months to get a pair of ISO-certified eclipse glasses to watch the total solar eclipse on April 8. But if you procrastinated and can’t find any, maybe your nearest welder can help you out.
Experts say welding helmets — specifically those which contain welding glass of a high shade number — are safe to view the eclipse through.
“The only ones that are safe for direct viewing of the Sun with your eyes are those of Shade 12 or higher. These are much darker than the filters used for most kinds of welding,” NASA wrote in an eclipse guide published ahead of the 2017 total solar eclipse. “If you have an old welder’s helmet around the house and are thinking of using it to view the Sun, make sure you know the filter’s shade number.”
Dr. Jason Brinton, an ophthalmologist with Brinton Vision in St. Louis, told Nexstar’s KTVI that he specifically recommends welders glass with a shade number of 14 — which is the darkest shade available, according to Phillips Safety, a manufacturer of welders’ gear and other safety equipment.
Viewers, however, will notice a big difference between ISO-approved eclipse glasses and welding glasses. The former allows more light through, while the latter blocks everything aside from “all visible light except for a small amount of green light,” Phillips Safety warns.
Sufficiently dark welding glasses may also be hard to come by, as they’re too dark for most traditional welding projects and can be “uncommon,” NASA warns.
Folks who still want to catch the eclipse have few other options for viewing the event safely, though Brinton says it’s possible to make your own pair of glasses from a Mylar sheet “that meets the same ISO standards” as the glasses.
Failing that, you can make a pinhole projector to project an image of the eclipes on a surface that’s safe for viewing.
And lest you get an inkling to reach for your regular sunglasses on April 4, think again.
“I still remember from the last eclipse people coming out of our building with multiple pairs of sunglasses on. I’ve got news: it doesn’t matter if you’ve got two, three, or four. No matter how dark they are, that does not qualify,” Brinton told KTVI.
“Looking through a camera viewfinder does not qualify. Looking through a telescope or binoculars or anything, even with various filters, those filters do not appropriately protect your eyes from the sun.”