On August 21, spectators across the continental United States will be able to experience the total solar eclipse for the first time in 38 years. With only a few days until the unforgettable spectacle, and in support of children's eye health and safety month, the American National Standards Institute (ANSI) reminds solar eclipse onlookers to use protective glasses that have been verified by an accredited testing laboratory to meet the International Organization for Standardization (ISO) 12312-2, Eye and face protection-sunglasses and related eyewear-Part 2: Filters for direct observation of the sun.
Ahead of the Great American Solar Eclipse, NASA has issued safety tips for solar spectators in search of suitable shades: The agency advises using solar viewers and glasses that have certification information listing the designated "ISO 12312-2 international standard" but be cautious of knock-off solar gear, which can pose a serious health risk.
Various counterfeit eclipse viewers that are stamped with the ISO logo and certification label are being sold to unsuspecting customers via e-commerce and other retailers. As Reuters reports, some of the fake shades are stamped with either "forged logos of reputable manufacturers or with phony safety labels." Fake eclipse glasses, which lack the protection filters needed to view the sun, can take a major toll on health: concentrated solar rays can cause serious injury to eyes and burn retinas.
To support consumer safety, the American Astronomical Society (AAS) reports that its AAS Solar Eclipse Task Force is actively working to verify that solar viewers come from a reputable manufacturer or one of their authorized dealers. The AAS task force has compiled a list of acceptable companies on its Reputable Vendors of Solar Filters & Viewers page.
"Task-force members have checked manufacturers' ISO paperwork to make sure it is complete and that it comes from an accredited testing facility, and they've asked manufacturers to identify their authorized resellers and dealers to identify the source of the products they're selling," the organization reported. "Only when everything checks out does the AAS add a vendor to its listing."
ANSI is the U.S. member body to ISO, and ANSI member and audited designator ASTM International serves as the ANSI-accredited U.S. TAG administrator to the ISO technical committee (TC) 94 Subcommittee (SC) 6 Eye and Face Protection, which supported the development of ISO 12312-2.
Safety Tips for Viewing the Total and Partial Solar Eclipse
Whereas all of North America can catch the eclipse of the sun on August 21, a "total" solar eclipse is another phenomenon: The moon will completely block the sun's bright face for about two minutes, an occurrence that will span across 14 states [see the list of states]turning day into night. During the total eclipse, planets and bright stars will be visible. Only observers who flock to the 70 mile-wide "path of totality" will get to experience the brief total eclipse, which is as bright as the full moon and is safe to view. But millions of others outside the path of totality will view the partial eclipse, which will last 2 to 3 hoursand be dangerously bright.
A safety list endorsed by AAS, the American Academy of Ophthalmology, the National Aeronautics and Space Administration (NASA), the American Academy of Optometry, the American Optometric Association, and the National Science Foundation (NSF) includes a few tips for viewing glasses and handheld solar viewers, which should meet all the following criteria:
- Have certification information with a designated ISO 12312-2 international standard
- Have the manufacturer's name and address printed somewhere on the product
- Not be used if they are older than three years, or have scratched or wrinkled lenses
- Not use homemade filters
- Ordinary sunglasses -- even very dark ones -- should not be used as a replacement for eclipse viewing glasses or handheld solar viewers
Find additional information on the official AAS eclipse website. Another helpful resource is the Xavier Jubier's Google Map, which reveals whether other specific locations are within the eclipse path on August 21, 2017, and supports zooming in to street level.