Is Your Gun Safe EMP Proof?

S&G Combination Lock
S&G combination lock on a gun safe

We covered EMP recently, and a reader emailed me about whether their gun safe would provide EMP protection to the contents stored inside.

I am not an expert on EMP, but I have done some research and feel comfortable answering this question. (Don’t let that stop you from doing your own research.)

To provide a detailed answer, I broke this simple question into five sub-questions and address each one.

Is Your Safe EMP Proof?

No, traditional gun and similar safes are not EMP proof. Yes, your safe is a big metal box, but do not mistake that for a Faraday cage. The gasket around the door seal prevents it from providing a complete EMP-proof Faraday cage-like protection.

Think twice before you decide to rip out the gasket. It is there to provide fire protection and is an important component to the UL Listing that says your safe is fire proof for 30, 60, or 90 minutes. I expect the chance of a house fire is greater than an EMP, so I would leave that gasket in there. Plus, there’s no guarantee that removing it would make your safe EMP proof.

Does EMP Hurt your Guns?

The good news is that an EMP strike will not hurt your guns. If you have a very high end, competitive target gun that uses electronic ignition, that could cease to work, but the traditional trigger mechanism that uses springs and sears will function just fine after an EMP, as will primers and gunpowder.

The bad news is that an electromagnetic pulse could damage any electronics mounted on your gun. This includes red dots, holographic sights, other sights with electronic components, lasers, night visions goggles, and even modern LED flashlights. Older tritium night sights will be unaffected, as will light-pipe sights that “collect” sunlight to show up during the day.

I expect the Tirjicon ACOG will function just fine after an EMP strike. I doubt that would be the case with an Aimpoint, Eotech or Holosun, but check with the manufacturer to be sure. Magnified optics with an illuminated reticle should also work, although the illumination may not.

If you store other electronic in your safe expecting them to be protected from an EMP, chances are you will be disappointed.

Will EMP Damage the Safe’s Lock?

EMP does not affect the standard or “old fashioned” combination dials like th eone picture above because they contain no electronics.

If an electromagnetic pulse is strong enough and the right frequency to damage small electronic devices in your safe, then it will damage an electronic lock, potentially preventing you from opening the safe. There is enough concern about this issue that at least one company has produced what they call an “EMP Lock.” This lock gives you the easy access of push button locks but has an manual dial as a fall back.

If your gun safe came with the lower-end electronic lock that uses a battery with no manual override, then you can pay a certified locksmith to replace it with an S&G or other lock that EMP will not damage. Expect the job to cost at least $200.

Can I Make my Safe EMP Proof?

There are several things you can do to improve the EMP protection offered by your safe. The easiest (and probably least effective) is to ground it and to unplug and remove electric cords used to power internal lights, dehumidifier rods, or other electric devices. I’ve seen gun safes with USB and Ethernet ports; I’d unplug those, too.

To provide the most protection, you would want to surround your safe with a Faraday cage. You can do this by building a cage from steel or copper wire mesh or by buying EMP cloth that has the wires woven into it. Cooper wire mesh is hard to find, but you can often get number 8 hardware cloth made from galvanized steel at farm stores. This has eight tiny squares per inch. You want to provide wooden or other non-conductive spacers to keep it from touching your safe, so there is an air gap between the Faraday cage and the safe to prevent transmission. The wire mesh Faraday cage should completely and seamlessly surround your safe.

A final option–which is not proven and is less effective than the full Faraday option described above — would be to seal the gap between the door and the frame with aluminum or other conductive tape. When I tape my ammo can Faraday cages, I first sand off the paint to provide good conductivity; I expect you would need to do this with your safe. You could also consider using a metal weather stripping or door seal between the door and the safe body. Nether of these approaches require removing or damaging the gasket.

Is there A Simpler Way to Protect my Optics?

You can remove your red dots and other electronic optics from your guns and store them in a small Faraday cage, or a pouch designed to act like a Faraday cage. Inside or out of your safe, this should protect them from an EMP.

You can find directions online and on YouTube to build your own Faraday cage using simple metal containers like a cookie tin. I hope to cover building one out of a .50 caliber ammo can soon.