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Comment by Jabbles | Hacker News Reader

I wonder if teflon coated shoes would be effective, if rubber are not?

Might have a problem with grip though...

https://en.wikipedia.org/wiki/Electrical_resistivity_and_con...

    I wonder if teflon coated shoes would be effective, if rubber are not?

No. You have to consider the distance through air. Electricity will still take the path of least resistance which, even if you're wearing rubber or teflon shoes, is still just a couple of centimeters out of the shoe and to the ground. As the article points out: the lightning just traveled a kilometer to get to you, so why would it care about a few centimeters or inches or meters of insulating material when it would just hop through the air around it and to the ground.---

--- I suppose that you could argue that a really large teflon pad would increase the aggregate resistance (through your nice, self-contained ocean and then over the large teflon pad) to such an extent that the lightning would pass by you and ground directly, but those would be giant shoes and the little gap between them would probably defeat the whole purpose of wearing giant teflon snow-shoes.

It doesn't seem inconceivable that wearing shoes takes you out of the path of least resistance as compared to some other path, say, the metal-framed shelving you are standing next to. I don't think wearing shoes is any kind of practical way to avoid getting hit by lightning but the 'kilometers of air' argument seems sort of wrongheaded. You don't need to become a more resistant path to ground than a kilometer of air - you just have to be more so than other paths. How long the discharge traveled to form that path doesn't really matter.

Unfortunately, simply reaching the ground may not be sufficient. The ground is not necessarily a good enough conductor to dissipate the full charge quickly. The rest of the charge flows near the ground looking for more ground.

Most lightning strike survivors are probably surviving "near misses", albeit sometimes ones where substantial electricity flowed through their body. A direct hit is probably going to be lethal nearly 100% of time -- there is a lot of energy in a lightning strike.

I once saw a very detailed article on what to do if under threat of lightning. Here is what I recall:

(1) Get away from high ground. (Duh.) (2) Get away from trees. (Duh.) (3) Do not go for low, low ground or any ditch. A very small local high piece of ground in a general lowish ground is good. (4) Do not lie down. (5) Squat down. (6) Put your heels together and spread the balls of your feet apart.

The latter non-obvious, points is because a strike will cause enormous local current near the ground in the immediate vicinity. Yes, the discharge wants to neutralize against ground, but the ground itself is not a good enough conductor to necessarily dissipate the full charge quickly. The discharge will therefore fly along the ground"as best it can.

What you want to do is avoid letting the powerful surface currents run right through your heart or head. Lying down is therefore bad. Putting your heels together might short circuit a current flow along the ground, while away from your torso. Being on a very smallish hill increases the chance that you can ride above the worst of near strike. A ditch or other low point puts your head and torso exactly where you do not want to be.

And, yes, your shoes are irrelevant.

In a true emergency, like if your hairs are already standing on end, sounds like all of the above should be discarded, with the exception of 5 and 6 - squat down, heels together, balls of feet apart.

Unless you could jump and roll away from the tree or something.

Lightening is a capacitor undergoing dielectric breakdown. The ground is one plate, the cloud is the other. Lightening is the evidence of dielectric breakdown. Dielectric breakdown on the order of millions of volts. A mile of air didn't help, no amount of teflon is going to help either.

I'm inclined to wonder if wearing a pointy metal crown would be better given the operating theory for lighting rods.

I figure my tinfoil hat is protection enough, though maybe a few pointy additions to it might help. Thanks for the idea.

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