If you’re going to watch a solar eclipse, you need to wear special glasses.
There’s not anything different about the sun or its radiation during the eclipse — it’s just that our moms were right when they told us not to stare at the sun because it will hurt your eyes.
If you’re one of the millions of people who will be staring at the sky Aug. 21, you gotta get those shades. They filter out nearly all of the incoming light so you can actually see the moon covering up the sun without damaging your eyes.
Earlier this week, the American Astronomical Society said it revised some of its eyewear advice “in response to alarming reports of potentially unsafe eclipse viewers flooding the market.”
The main issue here is the certification. Since you’re going to be using them to stare at the sun, they need to filter out more light than the standard sunglasses pinned to your visor.
The lenses should block out the majority of light to keep your eyes from being damaged. The certification process allows a manufacturer to include a special label, the ISO stamp, so you — the buyer — know it’s actually going to protect your eyes.
Three weeks away from the greatest solar eclipse of most of our lifetimes in the United States, you don’t have to look far online to find hundreds of glasses manufacturers. In one of my recent searches, Amazon listed seven pages of results.
All of the products describe themselves as having met the standard, but it would be difficult for the average buyer to ascertain whether the glasses have actually been approved.
Given the massive influx of vendors and manufacturers, “it is no longer sufficient to look for the logo of the International Organization for Standardization (ISO),” the American Astronomical Society wrote.
There appear to be a number of issues — hundreds of online manufacturers, rapidly increasing sales and giant piles of certification paperwork — all of which add up to chaos in the eclipse-glasses marketplace.
One manufacturer told Quartz that its sales are increasing at a rate of 400 to 500 percent as the eclipse approaches. Given that kind of market, it’s not surprising that some companies may decide to skip the certification hoops before taking their product to storefronts.
But “uncertified” doesn’t necessarily mean “unsafe.” It just means they haven’t been officially tested by a certification organization.
In fact, Quartz reports that in cases where the IP number is being used without certification, the glasses themselves are not harmful.
Given all this — and in an effort to reduce your level of anxiety and prevent thousands of perfectly fine eclipse glasses from winding up in the landfill — there is a simple way to test whether your solar eclipse glasses are safe.
“You shouldn’t be able to see anything through a safe solar filter except the Sun itself or something comparably bright, such as the Sun reflected in a mirror, a sunglint off shiny metal, the hot filament of an unfrosted incandescent light bulb, a bright halogen light bulb, a bright-white LED flashlight , or an arc-welder’s torch,” the AAS wrote in its press release.
“All such sources should appear quite dim through a solar viewer.”
If you can see anything else through the film, toss the glasses and find a pair that works.
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