(Note: “filters” is mentioned throughout this discussion and refers to the special filter material that is made specifically for viewing the sun. This filter material is made by several companies, and can be found in many different forms – from eclipse glasses to sheets that can be cut and made into customized filters for cameras, telescopes, and binoculars, and solid glass filters for use with large telescopes. Do NOT try to improvise your own material – ONLY use filter material that is ISO Certified, and has been specifically manufactured and sold as safe for direct solar viewing!)
If you’ve read our piece on what it is about looking at the Sun that hurts your eyes, you can see that it’s dangerous! We all have this almost instinctive thing we do whenever the Sun accidentally gets into our field of vision – we squint, we close our eyes, we turn our heads away almost immediately, because the Sun is just too bright to look at.
Normally, this is all the protection we need, to make sure our eyes stay safe – we just simply DON’T look at the Sun!
So now that there’s a total eclipse of the Sun going on, and we want to look at it because we’ve heard it’s really cool, our natural instincts get in the way. This time, we WANT to look at the Sun, and some people actually do it anyway – and hurt their eyes. (We have to tell you again, DON’T LOOK at the Sun without proper eye protection!)
Other people try to use something to block the Sun’s rays that won’t be good enough, and they run the risk of seriously injuring their eyes. So how are we able to view and enjoy the eclipse in a way that won’t hurt our eyes?
There are indeed filters that are specially designed to put in front of your eyes and look through, that will cut down on all the dangerous rays of the Sun enough to allow you to look at it without hurting your eyes.
Some filters are very expensive, and are used on telescopes and cameras so that even the magnified rays of the Sun won’t be harmful. There are other filters that are not very expensive at all, and they work just as well for the short period of time that people are going to want to look at the Sun while it’s being eclipsed. The simplest ones are called Eclipse Glasses.
Certifies Eclipse Glasses
When an eclipse comes around, EVERYBODY wants to get eclipse glasses so they can take part in the event. And as with all equipment that’s used to make sure you stay safe while doing something that could be dangerous, there have to be standards that are followed in design, manufacture, storage, shipping, and use to make sure the eclipse glasses you want to use are going to work.
The ISO (International Standards Organization) is a worldwide organization that publishes these detailed standards on literally everything you can think of. Some standards have been around for a long time, and others are being created every year. The standards exist to protect the public from using devices or methods that are flawed, damaged, not well-designed, or that just plain don’t work. They are written by leading experts, confirmed by other leading experts, and then tested again and again to make sure that if products follow every detail of the standard, they will be safe to use.
In 2015, the ISO came out with a standard for solar viewing material, called “ISO 12312-2”. It was written by Dr. Ralph Chou, who is one of the world’s leading experts on eye safety during eclipses – because he himself is an eclipse chaser and a professor of optometry. This standard is incredibly detailed, and defines all the scientific details about how much of each type of light the filters have to follow in order to be OK per the standard.
The standard had been reviewed for years for accuracy, and was finally approved for use in 2015. All reputable manufacturers of eclipse glasses and the filter material itself make the filters they use in their eclipse glasses to follow this standard. So, if you use glasses made by these vendors, and use them correctly, you will be fine.
The American Astronomical Society has a great page that explains everything about eclipse glasses and eye safety as well.
But there’s more, unfortunately. Because the demand for eclipse glasses was so great, some companies out there have made eclipse glasses that don’t conform to the standard, but they are putting the ISO logo on the glasses anyway. This is very bad, because people won’t really know if their glasses are ISO certified just by looking at them.
We here at maineeclipse.com (Southern Aroostook Development Corporation Attraction Committee) work directly with the manufacturers of certified, USA-made eclipse glasses, and we stock and sell ONLY glasses that are made by these companies. You can buy your very own pair of certified eclipse glasses here and relax knowing that you will be able to view and enjoy the eclipse safely.
