There are 15 U.S. states along the path of totality – the area that will experience the greatest darkness – for the April 8 total solar eclipse. The rest of the contiguous U.S. will get the chance to see some level of the eclipse as the moon blocks out the sun.

No matter where you are, however, safety is a major issue when it comes to viewing an eclipse.

Except during the brief total phase of the eclipse when the moon completely blocks the sun’s bright face, it’s not safe to look at the eclipse without specialized eye protection for solar viewing, NASA said on its eclipse information page. If you’re watching the eclipse directly, you will need solar viewing glasses – also known as eclipse glasses – or a handheld solar viewer.

Regular sunglasses, no matter how dark, won’t work. Safe solar viewers are thousands of times darker and must be ISO certified.

And, without a special solar filter, it’s also dangerous to watch any part of the bright sun through a camera lens, binoculars or telescope. It’s also not safe to look through a camera lens, binoculars or telescope if you’re wearing eclipse glasses or using a handheld solar viewer, NASA warns. The concentrated solar rays will but through the filter and could cause serious eye injury.

How to watch the eclipse safely, per NASA

• Only use solar glasses that have been certified as safe. Once you get them, inspect them to make sure they aren’t torn, scratched or damaged in some other way. If they are, throw them away.
• Make sure children are supervised while watching the eclipse through any of the approved methods.
• Don’t have solar glasses? You can use an indirect viewing method that does not involve looking directly at the sun. You can make a pinhole projector by making a small opening, for example, a hole punched in an index card, to project the image of the sun on a nearby surface. You must keep the sun at your back, however. You don’t look at the sun through the pinhole. You can go here to see directions for making a pinhole projector or watch NASA’s video below.
• If you want to watch the eclipse through a camera, telescope, binoculars or other optical device, NASA recommends seeking the help of an astronomer to make sure the filter fits correctly.
• You can wear eclipse glasses to safely view the sun during the partial phases before and after totality. You can watch the eclipse directly only when the moon completely covers the sun during totality. You will know it’s safe when you can no longer see any part of the sun through the eclipse glasses or solar viewer. This will only work, however, if you’re in the path of totality and even then, it’s only for a few minutes. As soon as you see even a little bit of bright sun reappear after totality, immediately put your glasses back on or use your viewing device.
• Don’t forget sunscreen. You could be outside watching the eclipse for several hours so your eyes aren’t the only thing that will need protection.]