This is a feature that many (but not all) safes have. Levels of fire-resistive are measured and rated, either by the manufacturer of the product or by Underwriter’s Laboratories (UL). A typical plastic lockbox sold by discount stores has a ½ hour, 350 degree label. This provides very little protection for papers. Some lockboxes and safes have no fire resistance at all! Good quality fire-resistive safes are available with 1 hour, 350 degree labels and even more. This is the minimum recommended level of protection for documents. The important thing here is to be an informed consumer. Don’t buy a $15 tin box and assume that your documents are safe! Read the exact label on the product you are considering. If it doesn’t have a rating, it isn’t fire-resistive! Protecting plastic media such as computer disks and photographs is a whole different matter! They are ruined long before the temperature reaches 350 degrees. A professional locksmith can educate you and help you select the right product to protect your cherished documents!