“Palusol”, which is a trademark of Odice, LLC, is the brand of intumescent seal used on most gun safes. When exposed to heat from a fire the product’s thermoplastic covering melts. The underlying material then expands as a foam which makes a barrier to prevent heat and smoke from entering the safe. Palusol is a great product, but there are limitations.
Shown left to right are three types of Palusol: “PL”; “PM”, what most safe manufacturers use; and “EFV”, which has two small fins on it.
A miner issue is that sometimes the safe manufacturer’s employees do not handle the product carefully. Dirty hands, oil or drywall dust sometime keep Palusol’s adhesive tape from sticking to the safe. The Palusol then peels off and the consumer needs to glue it back into place.
More importantly, doors on some gun safes fit so poorly that the gap between the door and the frame is too big for Palusol to fill when it expands. In this case, heat and smoke will be allowed to enter the safe even after the seal expands.
Odice’s sales material states that for best protection, Palusol PM should be installed flush in a routed groove to direct the expansion of the material properly. None of the safe manufacturers install Palusol this way.
Odice says that Palusol should not be exposed to temperatures greater than 104 degrees for extended lengths of time. It seems, then, that Palusol might lose its effectiveness when the gun safe is in a garage in a part of the country where the temps get that hot.
Here is the biggest problem: Odice states that Palusol is activated at temps between 212 and 302 degrees F. That means that smoke and heat perhaps as high as 300 degrees can pour into most gun safes until the seal’s thermoplastic melts and the inner material expands. In many house fires one part of the house can burn while other areas do not. But the black sooty smoke infiltrates the entire house, and the safe. We have seen a number of gun safes which were not damaged by heat, but whose contents were destroyed by smoke and low level heat, because the seals did not get hot enough to expand.
So then how do you get real fire protection? Buy a gun safe with a door that fits well, and which has two seals. A cold seal or smoke seal is critical because it works all the time – before the expanding seal actually expands. Pictured above is the frame of a Fort Knox Defender. The black stripe on the left is Palusol PM, but to the right is a fire resistant fin-type seal which makes the safe airtight all the time. Infiltration of smoke, and air from 212 F to 302 F, will be greatly reduced. On American Security safes there is a foam compression-type seal which accomplishes the same thing. But most gun safes, even expensive ones, do not have the important second seal.