UL Ratings for Safes, Explained: RSC, TL-15, TL-30 and Class 350

Short answer: UL ratings for safes come from several different standards, and each one answers a different question. UL 1037 rates gun safes as Residential Security Containers (RSC), Levels I to III — burglary. UL 687 rates higher-security safes as TL-15, TL-30 and up — burglary, by tool class. UL 72 rates fire resistance as a class (Class 350, 150, 125) plus a time. UL 768 and UL 2058 rate the lock alone. A "B rate" isn't a UL rating at all. Read which standard the label names before you read anything else.

UL safe ratings explained in one sentence: the letters tell you which test, and the test tells you what was protected against. This guide walks through each rating you'll see on a listing, what the test involved where the public record says so, and what the rating does not cover. If you want rated products rather than definitions, our UL-rated safes page lists them by rating.

What does UL rated mean on a safe

It means a product was evaluated against a named UL standard. That last part is the one that matters. "UL rated" on its own is half a sentence.

Safes can carry ratings under different standards for different things:

• Burglary, gun safes: UL 1037 (Residential Security Container)
• Burglary, high-security safes: UL 687 (TL, TRTL and X6 classes)
• Fire: UL 72 (class and time rating)
• Locks: UL 768 for mechanical combination locks, UL 2058 for high-security electronic locks

UL isn't the only lab that can test to these standards. Intertek, which issues the ETL marks, is an OSHA-recognized Nationally Recognized Testing Laboratory (NRTL). California's gun safe standard, for example, accepts a safe certified or listed as meeting the UL RSC standard by any NRTL.

UL 1037 and the RSC rating

UL 1037 is UL's standard for antitheft alarms and devices. Its scope also covers Residential Security Containers at performance Levels I, II and III. UL Solutions lists it as the standard gun safes are evaluated to.

The UL RSC rating most gun safes carry is Level I. The requirements, as reproduced in Intertek's notice of the 2016 revision:

• Level I: a 5-minute attack by one operator familiar with the safe's construction, using common hand tools and a small electric drill. Failure is the door opening or a 4-inch hand-hole in any surface.
• Level II: 10 minutes of net working time by two experienced operators with more aggressive tools. Failure is a 6-square-inch opening through the door or front face. The safe must weigh 750 lb or more or be anchorable, with a UL 768 Group 2M or UL 2058 lock.
• Level III: 10 minutes by two operators, now including abrasive cutting wheels and power saws. Failure is a 2-square-inch opening through the door or body. Lock: UL 768 Group 1 or UL 2058.

An RSC rating is a floor, not a vault. It's a useful floor. Level I tells you the safe stood up to a short, defined attack by someone who knew its construction. It doesn't tell you it will outlast an unlimited one. Our guide to gun safe testing covers how that compares with fire testing and in-house claims.

What is a TL-rated safe: TL-15 vs TL-30

TL ratings come from UL 687, Burglary-Resistant Safes. The UL 687 scope lists the classes:

• TL-15 and TL-30: tool-resistant, door and front face
• TRTL-30: torch and tool resistant
• X6 classes (TL-15X6, TL-30X6, TRTL-15X6, TRTL-30X6, TRTL-60X6, TXTL-60X6): the same idea, tested on all six sides

UL 687 covers combination-locked safes. The current edition is Edition 15, reaffirmed in July 2025.

TL 15 vs TL 30: both are in the same family, and TL-30 is the higher class. What I can't give you here is the exact attack time or opening size from UL itself. The full text of UL 687 isn't freely published, and the explanations I found came from retailers. When a figure isn't verified from the standard, it stays out of this page. The rating's own documentation, from the manufacturer or the listing, is where to read the details for a specific safe.

What a TL 30 safe means in practice: a different class of product from a typical gun safe. TL-rated safes sit at the high-security end of the market. The Marketing Department sometimes borrows the letters for a gun safe that has never met the standard, so look for the rating on the safe's UL label, not in the ad copy.

UL 72 Class 350 and the other fire classes

UL 72 is the fire standard, and its label has two parts according to UL: a class, which is the maximum interior temperature reached during testing, and a time rating, which is how long the product withstood the fire.

The scope of the current edition (17th, January 27, 2026) says what each class is for:

• Class 350 (350°F): intended to protect paper records
• Class 150 (150°F): paper and non-paper records
• Class 125 (125°F): also flexible computer disks

Time ratings come in fixed steps, commonly listed as ½, 1 or 2 hours and longer. Some products are also impact-rated: UL tests them before and after a 30-foot drop and then returns them to the furnace.

"Class 350, 1 hour" is a complete fire rating. A temperature with no class, no lab and no time is not. Our page on whether gun safes are fire-rated goes further on reading fire claims.

UL 768 and UL 2058: the lock has its own rating

Locks are rated separately from the safe they sit in.

• UL 768 covers mechanical combination locks for safes and vaults and tests their resistance to being opened by sight, touch or hearing. It does not cover electronic locks.
• UL 2058 is UL's Outline of Investigation for High-Security Electronic Locks. It's the electronic-lock benchmark referenced for RSC Levels II and III.

UL 768 groups locks into classes such as Group 2M and Group 1, and RSC Levels II and III require specific groups. I haven't verified the test durations for each group from UL, so they aren't quoted here.

What is a B-rated safe

A B rate is an insurance construction classification, not a UL test. Liberty Safe describes it as a safe with a body less than ½ inch thick and a door less than 1 inch thick, and says the class has not been tested by Underwriters Laboratories. A "C" class, by the same description, has a body of at least ½ inch and a door of at least 1 inch — and also no UL test.

Construction classes describe what a safe is made of. UL ratings describe what happened when someone attacked one. Both are information. Only one involved a stopwatch.

Here's the catch: a UL-listed lock is not a UL-rated safe

This is the trick listings play most often, usually without meaning to. A safe can have a UL-listed lock — a UL 768 combination lock or a UL 2058 electronic lock — and no rating on the safe itself. The lock was tested. The box it's bolted to wasn't.

Read the label and ask which standard it names:

• "UL listed lock" — the lock was evaluated
• "UL RSC" — the container was evaluated for burglary under UL 1037
• "UL 72 Class 350, 1 hour" — the container was evaluated for fire
• "TL-15" — the container was evaluated under UL 687

The same check works for fire. A UL RSC rating is burglary only; it says nothing about fire, which is rated separately under UL 72.

Skip it if: when you don't need a UL rating

• You're buying a small lock box or document box. Many aren't designed to be RSCs. Judge them on the lock, the backup and any fire rating that names a lab.
• You need California compliance. The state's standard accepts either a construction standard or an NRTL-listed RSC. Read the official page, not a summary.
• You're comparing TL-rated safes. Ask the seller for the UL listing and the test details for that model; a guide can't substitute for the paperwork.
• The safe can't be anchored. RSC Levels II and III assume 750 lb or an anchor. A light safe that isn't bolted down won't behave like its rating.

That's the label decoded. Find the UL mark on the safe you're considering, write down which standard it names, and check it against the list above. If the listing only says "UL" and nothing after it, ask the manufacturer which standard — and get the answer in writing.