If you are concerned about keeping documents safe from fire, a good idea is to put them in a good sealable freezer bag and put them in your freezer. I am a Fire Chief and your freezer section of your fridge is very well insulated to keep cold in and it also keeps heat out. It may not be secure but most thieves are looking for valuables not documents and they seldom look for them in a freezer. If there are documents you don't often need it may be a good idea to use a home vacuum packer to seal them to protect them from moisture but a good sealable freezer bag works well. You might also keep some cold hard cash there as well! Happy traveling!
