Shine On

Question:

Are survival blankets dangerous to use during electrical storms?

Submitted by – D.R., Sacramento, CA

Answer:

Go ahead and wrap up, especially if you need extra warmth or shelter. Mylar, the silvery material in most solar blankets, is a polyester insulator designed to trap body heat. Metallic coatings can make it conductive, but lightning safety is less about what you are holding and more about where you are standing (or crouching, as you should be doing if an electrical storm is on top of you). A person on an exposed ridge is more likely to get zapped than someone in a protected valley, and a Mylar blanket won’t alter the odds. “A nearby strike would go right through it,” says James Kirtley, professor of electrical engineering at MIT. When threatened by lightning, it’s smart to ditch metal gear like ice axes, tent poles, and cook sets–but it’s even smarter to avoid exposed locations and to descend fast.