On Aug. 21, people will be flocking to parts of the Lowcountry to view the first total solar eclipse in the U.S. since 1979.

Although everyone knows the age-old advice “don’t stare at the sun,” common sense sometimes goes out the window when events like these come about.

A few minutes of a really cool sight, however, is not worth a permanent blind spot in your vision. You must protect your eyes if you plan to view the eclipse.

Regular or prescription sunglasses are not enough to directly view the sun, even if it is partially eclipsed by the moon.

The only time at which it will be safe to view the eclipse without approved filters is during the approximately 2.5 minutes of totality, which will not happen in Bluffton.

Four companies have produced “eclipse glasses” that meet the ISO 12312-2 safety standards for viewing: Rainbow Symphony, American Paper Optics, Thousand Oaks Optical and TSE 17.

There are reports of counterfeit eclipse glasses being sold online and locally that even have the “ISO 12312-2” logo on their product. So, be sure to purchase one of your eclipse viewers directly from the manufacturer or one of their authorized dealers.

Alternatively, you can safely view the eclipse by making a pinhole projection onto the ground with the sun behind you. All you need is a piece of cardstock paper and aluminum foil.

Cut a square hole in the middle of the paper, tape the foil over the hole, poke a hole in the foil, and you’re done. With the sun at your back, hold the paper and see the projection of the sun on the ground in front of you.

Directly viewing the sun can cause damage to multiple structures in the eye. The cornea at the front of the eye can be damaged, which is called UV keratopathy.

This is most commonly seen in welders or tanning bed users who don’t properly protect their eyes.

It causes pain, redness, tearing, and blurred vision but symptoms worsen six to 12 hours after exposure. This is generally reversible with treatment.

Solar retinopathy, or damage to the back of the eye from sun gazing, is most commonly caused by viewing eclipses. The photoreceptors in the macula, or central retina, and the pigmented cells beneath are disturbed to various degrees.

There is no treatment for this condition, and some people are left with a permanent blind spot in their central vision.

Wear your eclipse glasses, and happy viewing!

Caroline Bundrick, O.D. is an optometrist practicing at Darling Eye Center, with offices in Bluffton and on Hilton Head Island.