I can speak only to the ones in army establishments. In my experience they had a whole array of makes, and some which bore absolutely no maker's name at all.

Regulations said that they should be anchored to the fabric of the building, ideally against an exterior wall. This usually took the form of being bricked into a pillar and the top being a slab of concrete.

These were graded according to various criteria as A, B or C although there were other classifications such as plate safes and sub standard plate safes. The main criteria, if memory serves, were did they have a fire resisting lining, were the bolts round (OK) or rectangilar (Bad, but if extremely heavy that was OK) the number of levers in the lock and was there an AED,

Were it possible to remove the safe, or the door, Central Ordnance Department, general trades branch, were able to upgrade the safe by changing the lock, generally to a CM Manifoil, or to add an AED.

I once had a very lovely Chatwood Duplex nightsafe which was classified as a sub standard plate safe as it had no lining. COD upgraded it to such an extent that it was superb. We didn't need the night safe facility so that was all welded up. In fact some time I really ought to start a new thread on that beauty. It had the old Chatwood dual control lock with key A and key B.

Once I was acting as a relief paymaster at a unit in the midlands. There there was an old 5' Ratner which had a non functioning Yale combination lock. If it had been my actual unit I would have had COD strip that out and replace it with a manifoil.