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As the total solar eclipse, which will take place in Mexico, the United States and Canada on April 8, approaches, experts are reminding spectators to grab a pair of eclipse glasses to safely view the celestial event – and to make sure it doesn’t be fake.
Counterfeit eclipse glasses are “polluting the market,” according to a post shared by the American Astronomical Society (AAS).
A total solar eclipse occurs when the moon passes between Earth and the sun, completely obscuring the sun’s face for a few moments. About 32 million people in the US live within the 115-mile-wide path of totality, or locations where the moon appears to completely cover the sun and the moon’s shadow falls on the Earth’s surface. People outside the path of totality will still be able to see a partial solar eclipse in which the moon blocks only part of the sun’s face.
The only time it’s safe to look at the sun without eye protection is during the totality of a total solar eclipse, or the brief period when the moon completely blocks the sun’s light, according to NASA.
Otherwise, experts say it’s imperative to wear certified eclipse glasses or use portable solar binoculars that meet a specific safety standard, known as ISO 12312-2, when viewing all other phases of a total or partial solar eclipse. The safety standard means that the lenses meet the international requirements for direct sunlight according to the AAS.
The lenses of solar eclipse glasses are made of black polymer, or resin infused with carbon particles, which blocks virtually all visible, infrared and ultraviolet light, according to The Planetary Society. And sunglasses don’t work in place of eclipse glasses or solar binoculars.
“Sunglasses, smoked glass, unfiltered telescopes or magnifying glasses and polarizing filters are unsafe. Inspect your eclipse glasses or handheld binoculars before use. If the device is cracked, scratched, or otherwise damaged, discard the device,” according to a press release from the American Optometric Association.
Looking at the sun without properly made eclipse glasses can lead to serious eye damage, from temporary vision loss to permanent blindness. But the AAS has discovered the production of fraudulent eclipse glasses that do not provide the necessary protection needed to safely view the sun without suffering eye damage.
This is how you recognize fake eclipse glasses
The counterfeit glasses may be difficult to spot because they contain information and even original artwork suggesting they were made by a well-known, reputable manufacturer of the products, but according to the AAS, several yet-to-be-identified factories actually made them.
“Until recently, the only counterfeit products we knew of were eclipse glasses with cardboard frames, made by an unknown factory in China, but printed with ‘Mfg. by: American Paper Optics’ (APO) on them,” the AAS shared in a press release. “APO is one of the largest US manufacturers of secure solar binoculars and prints its name and address on its eclipse glasses, while the Chinese copycat products have APO’s name but not the address. Fortunately, these particular counterfeits appear to be safe.”
But close investigation by the AAS has revealed that more unidentified factories are producing counterfeit glasses printed with the name and address of a Chinese factory called Cangnan County Qiwei Craft Co., which makes safe products. Some counterfeit glasses also bear the name or logo of Solar Eclipse International, Canada, Qiwei’s North American distributor.
While some glasses appear safe and virtually indistinguishable from genuine Qiwei products, others have lenses that are about as dark as sunglasses, meaning they are not safe to use, according to the AAS.
“Filters that provide a safe, comfortable view of the sun generally emit between 1 part in 100,000 (0.001%) and 1 part in 2,000,000 (0.00005%) of visible light,” says Rick Fienberg, project manager of the AAS Solar Eclipse Task Force, in a statement. “Sun filters are at least a thousand times darker than even the darkest regular sunglasses.”
The AAS has compiled a list of safe manufacturers and resellers of eclipse glasses and filters for optical devices, including cameras and smartphones. The AAS eclipse task force has confirmed that solar binoculars and glasses made by all major manufacturers of the products in the US and across Europe, as well as some Chinese manufacturers, have been laboratory tested.
“We now recommend that if you wish to purchase solar binoculars online, you should only purchase them from sites you reach by clicking on the links in our list, or from a seller whose identity you can verify and whose name appears on our list” , according to the AAS. “We recommend not purchasing eclipse glasses from random sellers on online marketplaces, even if they claim they get their products from a supplier on our list or are approved by the AAS or NASA. The US Space Agency does not approve commercial products, so any statement to the contrary is a warning sign that you are not dealing with a reputable seller. Likewise, if a supplier claims to be on the AAS supplier list but you can’t find them there, you shouldn’t trust them.
Tips for safely viewing the solar eclipse and testing your glasses
For those who didn’t purchase their glasses directly from a vetted seller on the list, there are ways to test out the eclipse glasses before April 8.
“There’s no way to tell if eclipse glasses are really safe just by looking at them,” Fienberg said, “but it’s easy to tell if they’re not safe.”
Try the glasses indoors first. Nothing should be visible through the lenses, and even the brightest lights should appear only very faintly. If furniture or wall decorations are visible through the lenses, these glasses are not safe for viewing the sun.
But if the glasses pass the indoor test, the AAS recommends putting them on outside on a sunny day and taking a look around. Again, nothing should be visible through the lenses unless the sun is reflecting off an exceptionally shiny surface, and even then the light will appear dim if the glasses are secure.
If the glasses pass the second test, try looking at the sun for less than a second. If the glasses are secure, the sun will look comfortably bright and will probably be white, yellow, orange or bluish white.
On the day of the solar eclipse, stand still and cover your eyes with glasses or solar binoculars before looking up. And never take off your glasses while looking at the sun. For those who wear glasses, wear eclipse glasses on top or hold a portable viewer in front of them.
And don’t forget to equip any camera lenses, binoculars or telescopes used to observe the solar eclipse with appropriate solar filters. Never look through an unfiltered optical device in this situation, even if you wear eclipse glasses.
Prevent eye damage due to eclipse
It is only safe to view the eclipse without eye protection when the moon completely obscures the sun and no light is visible – and be sure to put your eclipse glasses back on before light appears again.
Looking at the sun without proper eye protection can result in solar retinopathy, or retinal damage from exposure to solar radiation. While the highly specialized cells in our eyes don’t feel pain, the rods, cones and photochemical reactors become inflamed and damaged when they look at the sun, says Ronald Benner, an optometrist and president of the American Optometric Association.
It’s a bit like the effect that happens when we see a camera flash go off, which can distort our vision for a few minutes before it disappears. But the intensity of solar retinopathy causes permanent damage that will not be immediately visible. Overnight, the cells can die and will not be replaced. There is no treatment for solar retinopathy. It may improve or worsen, but it is a permanent condition.
The changes in a person’s vision depend on the type of damage done, and they can occur in one or both eyes.
“The retina is an extension of the brain, so it’s actually neurological tissue, and if you damage that, it doesn’t always come back,” says Benner. “If you damage one cell, that cell may never be the same again. But if you damage a group of cells, you get spotty vision, like someone dabbed oil on your windshield. If you damage them just a little and they don’t die completely, color vision will change. What can you do about it? There is no other option than to prevent it.”
If the damage occurs in the center of a person’s visual field, it can affect the ability to read or recognize faces, Benner said.
If you experience vision problems or eye discomfort after viewing the solar eclipse, Benner recommends making an appointment immediately through the American Optometric Association’s doctor locator. Symptoms can take hours to several days to manifest, and these include loss of central vision, altered color vision, or distorted vision.
“For most people, it’s a change in color vision,” Benner said. “The next morning the colors just don’t look right, or the color is faded, or the color is kind of blurry all the time. For others, it may be that they actually have gaps in their vision.”
And always monitor children wearing eclipse glasses to make sure they don’t take them off and look directly at the sun. Benner recommends parents talk to their children about how and when to view the solar eclipse and when to put on and take off their glasses. And if parents are concerned about their children taking off their glasses at the wrong time, make plans to watch the eclipse on TV or use the pinhole projection method to view the eclipse indirectly.
“Make sure you protect not only yourself, but more importantly your children,” Benner said. “If your child sustains eye damage, he/she will have to live with it for the rest of his life. And maybe they can’t tell you, ‘I can’t see clearly in one eye.’”
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