Flashlights vs EMP Electro Magnetic Pulse

A curious question popped into my head: What flashlight designs would most likely still be usable after an EMP event?

- old school direct drive incandescent?
- dual circuitry LED (like ArmyTek's Predator Pro)?

As we all know, a nuclear device will set off a powerful EMP, but these days, there are also devices developed specifically to trigger an EMP, and a friend of mine claims that a power pole transformer/junction box blowing up ~30 feet away from him triggered an EMP that killed his Casio watch (not to mentioned scaring the heck out of him).

Any ideas? I even recall someone mentioning that they have their SHTF flashlights stashed in a Faraday cage for just such a reason.

- is there anything about an LED that might make it inherently more susceptible than an incandescent bulb?
- does it matter if there are batteries in the light or if it's On vs Off? AFAIK, most electronics are most vulnerable when they're powered (unless specifically shielded against EMP).
- how vulnerable are spare batteries?


Max

Google'd it, Site:CPF.org EMP to find:
If the EMP is strong enough to kill your light, you're probably just prolonging the inevitable unless you already live on a farm with seed re-use, twenty armed men, and a bullet-loading press. Very few people have test rigs that really check for the effects of a large-scale EMP event. Smaller test rigs can be made, and guesses can be made. This is complicated because an EMP is a multistage event.

Edit: I believe that I have killed flashlights with static discharges. This is certainly different from an EMP, but then I spend time in 200kV static fields, not powerful,l changing magnetic effects.

There's no excuses not to have a faraday cage in every home with a few basic electronic dvices (a couple good lights, weather radio and walkie talkie/ HAM/longer range radio equipment) you can purchase these hi-tech faraday cages at any army surplus / camping/outdoor stores for about $12, there called ammo cans (or any other tightly sealed metal box would work too, trash cans, coffee cans with a metal lid, any metal box will do)

The HDS lights (at least the legacy clickies) are supposed to be EMP proof. If you're trying to convince someone to get one and nothing has worked: mention this .

There's at least a dozen lengthy threads on this topic, be sure to search for plenty of reading. Some highlights:

- An ICBM attack may include an EMP-specific stage where a warhead is detonated ~120 miles over the target area; there would be no blast/heat/radioactive damage, but it would blackout multiple states underneath the detonation. This means you may still be subject to an EMP attack even if you live nowhere near where an actual nuclear blast occurs.

- A microwave, if grounded, is an excellent Faraday cage.

- Roughly two-thirds of cars will survive an EMP attack.

etc.

Wouldn't most flashlight bodies serve as Faraday cages for enclosed electronics?

JCD said:

Wouldn't most flashlight bodies serve as Faraday cages for enclosed electronics?

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It depends on several things, including geometry of the 'conductive shell.' Radio Frequency shielding is sensitive to penetration size. In some cases, the shell with a small hole will have a concentrated field in some areas. I do not know if the hole in the aluminum reflector will concentrate magnetic fields through the LED and circuitry there.

I have the ammo cans!

ragweed said:

I have the ammo cans!

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Me too but where will my ammo go?

Cereal_Killer said:

There's no excuses not to have a faraday cage in every home with a few basic electronic dvices (a couple good lights, weather radio and walkie talkie/ HAM/longer range radio equipment) you can purchase these hi-tech faraday cages at any army surplus / camping/outdoor stores for about $12, there called ammo cans (or any other tightly sealed metal box would work too, trash cans, coffee cans with a metal lid, any metal box will do)

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You can buy a fire safe and kill several birds with one stone. But the thing AnAppleSnail quoted is pretty much spot-on: unless you have the equipment to survive in a place like Somalia, you're not going to be better-off than your neighbors for long.

Being able to last 12 months or 18 months, sure goes a long way towards getting past whatever the first period or two, or three, offers.

I keep my small transistor radio in a mylar bag. I read somewhere that that is an effective means to protect it from an EMP. It is also encased in a cardboard-like sheath, insulating it from actually touching the bag. I don't know why that is there. Is it something that I read? I don't recall.

Last year a PBS station aired a few worst case scenario survival situations. One of them being a nuclear dirty bomb blast. They mentioned that cars that were running at the time would be toast, but those that were not running would be OK. The survivor selected a diesel powered SUV for his vehicle, and ran it on cooking oil.

Newer diesels are computer controlled just as their gasoline counter parts are. The computers of cars and trucks have a small amount of current supplied to them at all times for "KAM... Keep Alive Memory". Did they miss that fact? Or does it NOT matter?

If it doesn't matter, then I imagine that flashlights that have a slight parasitic drain are not more suseptible to damage than others. OTOH, if it does matter, then I suspect that lights with "memory" may be more likely to be damaged.

One thing for sure... a zippo lighter, and candles won't be affected. :thumbsup:

The_Driver said:

The HDS lights (at least the legacy clickies) are supposed to be EMP proof. If you're trying to convince someone to get one and nothing has worked: mention this .

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I find this hard to believe. Unless they use a metalized, conductive, front crystal. The LED itself will not be able to handle the E-fields from a large EMP. I fully believe the head and tube could act as a Faraday cage and protect the electronics. But the emitter, I think it would be vulnerable depending on its orientation to the field.

Lots of interesting replies. I also didn't realize there were numerous other threads about flashlights and EMPs. Looks like I have quite a bit of interesting reading material.


Max

Poppy said:

a nuclear dirty bomb blast.

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Much more likely than an EMP attack, and much more difficult to prepare for. A dirty bomb is some radioactive material included with an explosive, there's no EMP, just radiation. Much cheaper and easier to put together than an actual nuclear weapon.

Regarding cars and EMP: Modern cars' engine electronics are well-shielded, where they are vulnerable are various ancillary electronics, like the gauges, displays, indicator lights, etc. Almost all modern cars exposed to a strong EMP will have some malfunctions on the dashboard, but will still run.

Almost all modern cars exposed to a strong EMP will have some malfunctions on the dashboard, but will still run.

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I'm not so sure, it depends on how the ECU will act once it detect a malfunction on external sensors/accessory circuits. It's hard to judge since it depend on the ECU's program.
Moreover, there might be some unshielded wiring that in a really strong EMP event will pick up some strong transitory frying sensors or ECU.

But I'm sure on one thing: in the old Europe at least the old Citroen Saxo 1.5 diesel will keep on working. It's a very small hatchback equipped with a very old kind of naturally aspirated diesel with mechanical injection. Basically almost an old style tractor engine capable of a decent 60 HP.

Once I had an interesting experience, I was driving one of this little car (was my parent's second family car) on an unpaved road at night in a wood when I hit the bottom of the engine bay on a big stone, it happen that the alternator belt got loose (the alternator bracket was bended) and the alternator stopped. I was left only with the car's battery running all the electrical stuff (electric power-steering included), I had to keep on driving.. when the battery got flat I was without driving lights, without power-steering (luckily in case of malfunction electrical ones are not getting so hard like hydraulic ones does) and without all electric devices (windows, spedometer, rev counter.. everything was dead), but the car was keeping running fine.

Than I did a mistake and stalled the engine.. since it was still hot, with the help of two friend, we pushed the car in 3rd gear and it started again without problems!!

Faraday bags (similar to the ones used to protect several computer parts) are easily findable on the Internet, and are cheap. I think it's a good idea to keep several electronic devices, such as flashlights and survival radios, inside an EMP/Faraday bag, stocking it somewhere in the house, just in case.

Yet, I also wonder if the body of most aluminum flashlight does protect it against moderate EMP.

While it is fine to store our disliked unused flashlights in faraday cages, and I'm trying to do that, the real focus of this discussion to me, is what about our best, top of the line flashlights and beloved EDC lights, our blackout lights on the shelves, in other words the lights that are not stored in faraday cages and the ones we would most want in an emergency.

I would like to hear more focus purely on the question of whether our led flashlights can be depended on being usable after an EMP, will my Fenix AA lights still be operating?

braddy said:

Will my Fenix AA lights still be operating?

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This is sort of like asking if a pot will burn your fingers when you pick it up. In broad strokes, it will depend on the EMP and your relative location. In particular, it seems to be difficult to do so. Contact one of several qualified EMP simulation agencies and submit a few flashlights. We'd love to find out, but nobody seems to have published such a test from a credible tester.

braddy said:

While it is fine to store our disliked unused flashlights in faraday cages, and I'm trying to do that, the real focus of this discussion to me, is what about our best, top of the line flashlights and beloved EDC lights, our blackout lights on the shelves, in other words the lights that are not stored in faraday cages and the ones we would most want in an emergency.

I would like to hear more focus purely on the question of whether our led flashlights can be depended on being usable after an EMP, will my Fenix AA lights still be operating?

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As has been pointed out, the emitter will be vulnerable in almost every LED light, since it is exposed. Depending on switch design, the light's regulator and the protective circuits for the cells would probably be protected by the flashlight case. If you're seriously concerned about EMP and don't want to use a Faraday cage or pouch, then storing your light bezel down on a metal shelf will improve the odds it survives an EMP, provided there is enough metal in the switch(es) to work as a Faraday cage.