Certification
Every pair of glasses we sell uses the same filter, tested to ISO 12312-2:2015 by an accredited laboratory and CE-certified as personal protective equipment. This page sets out exactly what that means, how to tell if any pair of eclipse glasses is safe, and answers the common eye-safety questions. For path and local times, see our 2028 eclipse guide.
The standard
ISO 12312-2:2015 is the international standard for filters used to look directly at the Sun. It sets limits on how much visible light, ultraviolet and infrared may pass through, requires the filter to be uniform and free of defects, and requires the maker's name and the standard to be printed on the product. A filter that passes lets through no more than 0.0032 percent of visible light. Ordinary sunglasses, welding glass below shade 14, smoked glass and camera filters are nowhere near that and are never safe.
The testing
Printing the standard on a frame proves nothing; counterfeit glasses before the 2017 and 2024 eclipses in the United States did exactly that. What matters is an independent test. Our filter is tested by ICS Laboratories, a laboratory accredited by A2LA, and retested every five years. The glasses are separately CE-certified as personal protective equipment under EU Regulation 2016/425 by Notified Body 2834, with the certificate valid to May 2031.
The paperwork
Every order ships with a certification pack. Every unit carries a QR code that resolves to its batch certificate, so a teacher, a council officer or a parent can check a pair on the spot. The full ISO test report and the CE certificate are available to any customer on request through the contact form.
Checking a pair yourself
Look for the ISO 12312-2 mark and the manufacturer's name on the frame. Hold the lenses up to a bright household lamp: you should see nothing except a dim image of the filament. Any pinprick of light, scratch or crease means that pair is finished. Undamaged filters do not expire, but check every pair before eclipse day, and never use eclipse glasses with binoculars, a telescope or a camera lens.
How to tell if eclipse glasses are safe
Five checks for any pair, from any seller, before 22 July 2028.
Look for ISO 12312-2 and the maker's name
The frame should carry the ISO 12312-2 reference and the name and address of the manufacturer or importer. No mark, no use. A mark alone is not proof, because counterfeit glasses copy it.
Ask for the test report
A genuine supplier can show a test report from an accredited laboratory for the filter, with the lab's name and the date. If a seller cannot or will not show one, buy elsewhere. Our report from ICS Laboratories is available on request.
Check the seller
Buy from an established supplier or a retailer that sells astronomy equipment. The American Astronomical Society publishes guidance on safe solar viewers and filters, and ARPANSA publishes Australian advice on watching a solar eclipse.
Do the lamp test
Indoors, hold the glasses up to a bright lamp. Through a safe filter you see nothing, or only a dim image of the bulb. Outdoors, the Sun should look like a sharp, comfortably dim orange or white disc. If you can see ordinary things around you, the filter is not dark enough.
Inspect for damage
Throw out any pair with a scratch, crease, pinhole, bubble or a filter coming away from the frame. Age alone does not matter; condition does.
Questions about certification and eye safety
What does ISO 12312-2:2015 actually test?
Transmission of visible light, ultraviolet and infrared through the filter, plus the uniformity of the filter, its resistance to damage, and the labelling. A compliant filter passes no more than 0.0032 percent of visible light and blocks almost all UV and IR. Sunglasses pass several thousand times more light than that.
Who tested your glasses?
ICS Laboratories in the United States, an A2LA-accredited testing laboratory, against ISO 12312-2:2015. The filter is retested every five years. The glasses are also CE-certified under EU PPE Regulation 2016/425 by Notified Body 2834, valid to May 2031.
Are they certified for Australia?
ISO 12312-2 is the international standard and the one Australian authorities refer to for eclipse viewers. Our testing lab advises the filter meets the applicable Australian eclipse-filter requirements. The test reports are available on request.
How do I check the pair in my hand?
Look for the ISO 12312-2 mark with the manufacturer's name printed on the frame, scan the QR code to confirm the batch certificate, and hold the lenses up to a bright lamp: you should see nothing but a dim filament, with no pinholes or scratches. Damaged pairs go in the bin.
Do eclipse glasses expire?
An undamaged filter that meets the standard does not expire. Condition is what matters. Check every pair before the day.
Can I get the test report?
Yes. The ISO 12312-2:2015 test report and the CE certificate are available to any customer on request through the contact page.
Are eclipse glasses from 2023 or 2024 still safe to use in 2028?
Yes, if they meet ISO 12312-2 and are undamaged. The filter does not expire. Check each pair for scratches, creases and pinholes, and confirm the ISO 12312-2 mark and the maker's name are on the frame.
How can I tell if the ISO certification on my glasses is fake?
A printed ISO 12312-2 mark is easy to copy. Ask the seller for the test report from an accredited laboratory and check that the lab and product match. Glasses that let you see ordinary indoor lights or your surroundings clearly are not safe, whatever the label says.
Can I use sunglasses or welding glass to watch the eclipse?
No. Sunglasses, even very dark ones, pass thousands of times too much light. Welding glass is only safe at shade 14 or darker, and most welding glass is lighter than that. Smoked glass, X-ray film and camera filters are not safe.
Do my eclipse glasses stay on during totality?
Yes. Wear certified ISO 12312-2 eclipse glasses for the whole eclipse, from first contact to last contact, including totality. Outside the path, the Sun is never fully covered, and the glasses stay on the whole time there too.
How long can I look at the Sun through eclipse glasses?
With undamaged ISO 12312-2 glasses you can look for as long as you like. For a short break, look down at the ground with the glasses still on. Keep them on until the eclipse is over.
Are paper eclipse glasses as safe as plastic ones?
Yes. Safety depends on the filter, not the frame. Paper and plastic frames that use an ISO 12312-2 filter give the same protection.
Can I wear eclipse glasses over my prescription glasses?
Yes. Put your normal glasses on first and the eclipse glasses over the top, and make sure no sunlight gets in around the edges.
Can children wear eclipse glasses?
Yes, with an adult supervising. Check the glasses fit and cover both eyes, and make sure the child keeps them on while looking at the Sun. Schools can use our eclipse safety plan for schools.
Can I use eclipse glasses with binoculars, a telescope or a camera?
No. Optics concentrate sunlight and will destroy the filter and your eye. Binoculars, telescopes and camera lenses need their own solar filter fitted over the front.
What happens if you look at an eclipse without protection?
Looking at the partly covered Sun can burn the retina, called solar retinopathy. It does not hurt at the time, and the damage can be permanent. If you have blurred vision or a blind spot after looking at the Sun, see an optometrist or doctor.