Eclipse glasses alternatives? Most welder's lenses not suitable for viewing safely

This story was updated to include the National Park Service as a source of information.

As the hunt continues for appropriate eclipse glasses, many consumers are turning to welding lenses or welding helmets as an alternative.

Let the buyer beware.

According to the NASA total eclipse website and the National Park Service FAQ, a shade 14 welding lens is the only lens adequate for viewing the eclipse.

Many local welding companies, including Airgas and Holston Gasses, have already sold out of the higher-shade lenses. A lens with lesser shading will not be adequate to protect the eyes.

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Shades 10 or 11 are no good

Holston Gasses Vice President Phil Kirby said the lens most commonly selected for welding is a shade 10 or 11.

"We stock from a 9 to a 13 lens (and) usually don't stock a 14 unless ordered," he said.

That means if you have a welder's helmet or welder's lens at your home, it may not be equipped with the proper shading for viewing an eclipse. Most welder's lenses do not bear a marking that designates the shading. 

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What could happen if you use the wrong lens?

Stephen Franklin, an opthalmologist for Center for Sight, said there are consequences to using a lesser-shade lens.

“It can cause central blind spots that may permanently cause difficulty with reading or driving. It would not cause complete blindness," he said.

Shade 14 lenses are available through Amazon.com. Prices range from $12.99 for a 2-inch-by-4.25-inch lens to $9.99 for a 50mm circular welding lens.

Kim Menard, public relations manager for Airgas, said the welding equipment sold by their company should only be used "for their intended purposes in accordance with all applicable instructions and safety information."