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The Edit — Records

Fireproof Safes: What UL Class 350 Certifies

Paper chars at about 400°F and a house fire runs past 1,700°F. A UL 72 Class 350 rating means an independent furnace test held the inside under 350°F for a stated number of hours.

ByEdith Mercer AI analyst·Published September 8, 2026·8 min read

This guide is research-led: we have not handled these units ourselves. If you buy through our links we may earn a commission — it never changes a pick. How we choose

THE EDIT — RECORDS Fireproof Safes: What UL Class 350 Certifies Paper chars at about 400°F and a house fire runs past 1,700°F. A UL 72 Class 350 rating means an independent FINANCE & INVESTING THE EDIT — RECORDS Fireproof Safes: What UL Class 350 Certifies FINANCE & INVESTING
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Fireproof is not a rating. UL 72, the standard for fire resistance of record protection equipment, is, and it produces a pair of figures: a class and a duration.

The quick list

Every pick, in order. Jump to the full test on any of them.

  1. Highest rated

    Andyer 2-Pocket Fireproof Document Bag, 15 x 11 in

    4.7 across 8,754 ratings on a bag rather than a box, which is the right tool for papers you need to grab and carry.

    4.7from 8,754 verified reviews
  2. Most-reviewed

    Amazon Basics Steel Security Safe with Electronic Keypad

    48,007 ratings makes this the most-evidenced home safe on the shelf, and it is a security box rather than a fire-rated one.

    4.6from 48,007 verified reviews
  3. The specialist

    SentrySafe Fireproof Document Box with Key Lock

    16,055 ratings from the brand that publishes its class and duration on the label, which is the whole point of this page.

    4.6from 16,055 verified reviews
  4. SentrySafe Fireproof and Waterproof File Safe

    15,049 ratings on a file-folder format, which keeps documents upright and findable rather than stacked flat.

    4.5from 15,049 verified reviews
  5. DocSafe Fireproof Document Organizer Box with Lock

    12,114 ratings on an organiser with passport and card slots, where the lock and the fire resistance both split in the reports.

    4.4from 12,114 verified reviews
  6. DAYI 2.0 Cu Ft Home Safe with Fireproof Bag

    4.4 is the lowest score here, and owners split on whether they would trust it with valuables at all.

    4.4from 902 verified reviews

The class is a temperature ceiling

A safe goes into a furnace that reaches past 1,700°F. Sensors inside record how hot the interior gets and for how long the safe holds the line.

Class 350 keeps the inside below 350°F. That is the paper class, because paper begins to char around 400°F, and 350 leaves a margin.

Class 150 keeps it below 150°F and adds a humidity limit. That is the class for magnetic tape and film.

Class 125 keeps it below 125°F with a tighter humidity limit, for floppy disks and other media that fail at low temperatures.

The number after the class is the hours: Class 350 1-Hour, Class 350 2-Hour. That duration matters more than most buyers realise, because it has to outlast the fire and the time before anyone reaches the safe.

Class Interior stays below Protects
350 350°F Paper documents, passports, currency
150 150°F, humidity limited Magnetic tape, film
125 125°F, tighter humidity Diskettes and low-temperature media
The specialist

SentrySafe Fireproof Document Box with Key Lock

16,055 ratings from the brand that publishes its class and duration on the label, which is the whole point of this page.

4.6from 16,055 verified reviews
Specifications for SentrySafe Fireproof Document Box with Key Lock
CapacityAbout 2 reams of paper
Owners praiseFits documents and mementos
WatchWeight and durability split

16,055 ratings from a brand that prints its class and duration on the label, which is what separates a rated safe from a heavy box. Owners report it holding about 2 reams of paper alongside mementos.

Weight and durability split in the reports, and weight is inherent: the fire resistance comes from a gypsum-based insulating layer between two steel skins, and that layer is most of what you are carrying.

Buy it if

  • You want a printed rating you can check
  • Papers and small valuables in one box

Don't buy it if

  • You need it to be portable

Digital media needs a different class

A Class 350 safe protects paper and destroys a hard drive. Electronics and magnetic media fail well below 350°F, which is the entire reason the lower classes exist.

That matters more now than it did, because the documents people most want to survive a fire are frequently on a drive rather than on paper. A Class 350 box with a backup drive in it is a box with a cooked drive in it.

The practical answer is usually not a media-rated safe, which is expensive. It is an off-site or cloud copy, with the safe holding the paper originals that cannot be reissued easily.

SentrySafe Fireproof and Waterproof File Safe

15,049 ratings on a file-folder format, which keeps documents upright and findable rather than stacked flat.

4.5from 15,049 verified reviews
Specifications for SentrySafe Fireproof and Waterproof File Safe
FormatHanging file folders
ProtectionFire and water rated
SuitsRecords kept in order

15,049 ratings on a file-folder format, which is a genuine functional difference: documents stand upright in hanging folders rather than stacking flat, so you can find one without emptying the box.

Fire and water are both rated here. Water matters because the thing that puts a house fire out is thousands of gallons of water, and an unrated box that survives the heat can still soak.

Buy it if

  • You file rather than pile
  • Water damage worries you as much as fire

Don't buy it if

  • You want the smallest possible box

Water rating is separate, and fires end in water

A fire rating says nothing about water. A separate immersion test covers that, and safes that pass it state a depth and a duration.

Think about the sequence. A fire is extinguished with water, then the building sits open to weather until anyone can enter. A box that held 350°F for an hour and then sat in six inches of water for two days has lost the papers anyway.

Ratings for both exist on the same product. Where only one is stated, assume the other was not tested.

Highest rated

Andyer 2-Pocket Fireproof Document Bag, 15 x 11 in

4.7 across 8,754 ratings on a bag rather than a box, which is the right tool for papers you need to grab and carry.

4.7from 8,754 verified reviews
Specifications for Andyer 2-Pocket Fireproof Document Bag, 15 x 11 in
FormatSoft bag, 2 zipped pockets
CapacityAbout 50 pages per pocket
WatchNo UL class stated

The highest-rated product here at 4.7 across 8,754 ratings, and it is a bag rather than a box. Owners describe sturdy zips, sealed seams and about 50 pages per pocket.

No UL class is stated, which is normal for soft bags and worth naming plainly. Its real use is as a grab layer inside a rated safe, or for the papers you would want to carry out with you.

Buy it if

  • You want papers portable as well as protected
  • It goes inside a safe as a second layer

Don't buy it if

  • You need a certified class and duration

DocSafe Fireproof Document Organizer Box with Lock

12,114 ratings on an organiser with passport and card slots, where the lock and the fire resistance both split in the reports.

4.4from 12,114 verified reviews
Specifications for DocSafe Fireproof Document Organizer Box with Lock
FormatOrganiser with slots
Owners praiseHolds multiple binders
WatchLock and fire claims split

12,114 ratings on an organiser with dedicated slots for passports and cards, which solves the finding problem that a plain box does not.

Both the lock and the fire resistance split in the owner reports. Read an unstated class as untested, and treat this as organisation with some protection rather than the reverse.

Buy it if

  • Passports and cards need their own slots
  • Organisation matters as much as protection

Don't buy it if

  • You want a certified class printed on it

Security and fire are two different products

Most-reviewed

Amazon Basics Steel Security Safe with Electronic Keypad

48,007 ratings makes this the most-evidenced home safe on the shelf, and it is a security box rather than a fire-rated one.

4.6from 48,007 verified reviews
Specifications for Amazon Basics Steel Security Safe with Electronic Keypad
PurposeSecurity, not fire rating
LockElectronic keypad
WatchKeypad reports split

48,007 ratings makes this the most-evidenced home safe available, and it is a security box: steel, a keypad, and no fire class.

That is a legitimate product for a legitimate problem, and it is not this one. Owners praise the size and the construction and split on the keypad. If fire is the risk you are addressing, a heavier gauge of steel does not help.

Buy it if

  • Theft and casual access are the problem
  • You want the deepest evidence base available

Don't buy it if

  • Fire is what you are protecting against

DAYI 2.0 Cu Ft Home Safe with Fireproof Bag

4.4 is the lowest score here, and owners split on whether they would trust it with valuables at all.

4.4from 902 verified reviews
Specifications for DAYI 2.0 Cu Ft Home Safe with Fireproof Bag
Capacity2.0 cubic feet
WatchKeypad failures reported
WatchOwners question the security

4.4 across 902 ratings is the thinnest evidence base here, and the owner reports are unusually direct: some say it works, others report keypad failures and say they would not trust it with valuables.

Volume is what it offers. For anything genuinely irreplaceable, a smaller box with a printed class and duration is the better purchase.

Buy it if

  • You need volume more than certification

Don't buy it if

  • The contents are genuinely irreplaceable

What to check on the label

Look for the class and the hours together. A product saying fireproof, fire resistant or heat insulated with no class has not been through the test, whatever temperature figure appears beside it.

Then check where it will sit. A safe on an upper floor may fall through a burnt-out floor, an impact the UL 72 test covers with a 30-foot drop onto rubble after the furnace.

Keep the paper originals that are slow to replace and back the rest up somewhere else entirely. Documenting what you own before you need to is the home inventory that survives a claim, and the same read-the-tested-figure habit runs through air purifier CADR.