Eclipse glasses: how to choose a pair that actually protects you
Eclipse glasses that are safe in the European Union carry two things printed on them: CE and EN ISO 12312-2. The phrase "ISO 12312-2 certified" on the box, on its own, proves nothing — it is the most common trap on the market and the one that shifts the most bad glasses.
Published 17 August 2026
Throughout the partial phase of the eclipse — from 09:40 to 10:45 and from 10:50 to 12:01 in Ceuta — looking at the Sun without a certified filter can burn your retina. It does not hurt while it is happening, because the retina has no pain receptors, and the damage can be permanent. This is not a subject for improvising or for saving money.
The two markings, and why you need both
ISO 12312-2 is the technical standard: it defines how much visible, ultraviolet and infrared radiation a filter may transmit for looking directly at the Sun. It is the right reference and it is cited worldwide.
What almost nobody explains is that in the European Union that is not sufficient. Eclipse glasses are category II personal protective equipment under Regulation (EU) 2016/425, and that requires something more: a CE mark backed by an EU type-examination certificate issued by an independent notified body. The standard says what the filter must be like; the CE mark evidences that a third party checked it. A large share of the product advertised online as "ISO 12312-2 certified" has no such certificate behind it.
How to check a pair you already own
- Look for “CE” and “EN ISO 12312-2” or “ISO 12312-2:2015” printed on the frame, not just on the packaging. If they only appear on the box, be suspicious.
- Look for the manufacturer's name and address. A product with no identifiable manufacturer leaves nobody to complain to.
- Hold them up to a bright bulb. If you can see anything besides the filament — the window frame, your hand, the shape of the lamp — the filter is not dense enough, or it is damaged.
- Run a hand over the film looking for scratches, creases or pinholes. A single pinhole voids them.
- Test them outdoors before the day: glancing at the Sun, you should see only an orange or whitish disc, sharp and without a halo. Nothing else from the surroundings.
What does not work, however often it is repeated
Where to buy them for the Ceuta eclipse
A year out, local supply does not exist yet: opticians, museums, planetariums, astronomy groups and shops in Ceuta can be expected to sell glasses in the months before, but today we cannot recommend a specific outlet because there is none. When there is, and once we can verify that the product carries a CE mark with its certificate, we will publish it here with names.
In the meantime, two pieces of advice that hold regardless. Buy early, because in the final week the good product sells out and the bad product appears. And if you buy online, ask the seller for the number of the EU type-examination certificate and of the notified body, then check that body in the European Commission's NANDO database. A serious seller gives you both; one who changes the subject is telling you they do not have them.
How many to buy
One per person, plus one or two spares per group. These are cardboard products that bend, scratch and get lost, and the partial phase lasts over two hours. Sharing one pair between five people means four of them are looking at the Sun unfiltered while they wait their turn — exactly the scenario you are trying to avoid.
And remember the one piece of good news: during the 4 minutes and 48 seconds of totality no filter is needed at all, because there is no solar disc left to filter. That is the moment to put them away and look.
Frequently asked questions
Is it enough for the glasses to say “ISO 12312-2”?
In the European Union, no. Eclipse glasses are category II PPE and require a CE mark backed by an EU type-examination certificate from a notified body. A reference to the ISO standard on its own — especially if it only appears on the box — does not evidence that anyone independent checked the product.
Can I use sunglasses to watch the eclipse?
No, never, not even stacked. A certified solar filter transmits on the order of a hundred thousand times less light than sunglasses. Looking at the Sun through sunglasses during the partial phase can cause permanent retinal damage.
Where can I buy eclipse glasses in Ceuta?
There are no local outlets yet — the eclipse is still too far off. Opticians and shops in the city can be expected to stock them in the months beforehand. When they do, and once we can verify the CE marking, we will publish it here.
Can I reuse glasses from a previous eclipse?
Only if they are intact: no scratches, pinholes or creases, and with the markings still legible. The old advice to discard them after three years is no longer in the standard, but the physical condition of the filter matters, and cardboard suffers in a drawer.
The illustrations are our own, and any figures shown in them come from the same Besselian computation as the tables elsewhere on the site. Sources and method