Cash & Fire Ratings

Cash Ratings

Some theft resistant safes are tested and rated by the amount of time an intruder takes to crack the safe open. The materials and tools used (eg. angle-grinders, drills, oxy-torches) can determine the time frame it takes to open the safe. Insurances companies will cash rate a safe based on the following criteria:

  1. Materials used to manufacture the safe ie. The thickness of the steel plate used on the door and walls
  2. Barrier materials used to fill the door and walls of the safe
  3. Quantity and types of locks on the door of the safe
  4. Quality of the mechanism holding the door when in the locked position ie. Number of locking bolts and directions they lock in.
  5. Re-locking devises attached to the mechanism to prevent forced entry

A cash rating will then be provided ranging from $5,000 - $500,000 in a non-supported situation (eg. no monitored alarm). If a monitored alarm is present the cash rating will be doubled (confirm this with your insurance company).

Fire Ratings

The fire rating labelling will indicate the degree of protection the safe and filing cabinet will provide its contents if exposed to extreme heat or fire.

Fire safe ratings can be based on specific time periods the safe will withstand effect from a fire ie. 30mins, 1 hour, 2 hours, 3 hours and 4 hours.

To establish the fire rating safes may undergo various fire resisting tests;

  1. Fire Endurance
  2. Fire and Impact Test
  3. Explosion Hazard Test
  4. Combined Explosion and Impact Test

There are various sources and authorities that provide fire ratings by under taking a diverse range of testing methods. Common testing authorities used by safe manufactures include;

  • U.L – Underwriters Laboratory
  • J.I.S – Japanese Industrial Standard
  • K.I.S – Korean Industrial Standard
  • ASNZS – Australian New Zealand Standards
  • Private Laboratory Testing

The most recognised fire testing is the U.L Class of fire protection which is described below. [Source Underwriter’s Laboratories -]

Underwriters Laboratories Testing Procedures

Underwriters Laboratories was founded in 1894 and is chartered as a not-for-profit independent testing organization. Its sole purpose and function is to test for public safety. At UL, a whole array of products, systems, devices and materials are stringently examined and tested to insure they pose no risk to life or health, or are not susceptible to fire or other hazards. Crime prevention is also a major UL concern. And, of course, those products designed to protect are put to trial to make sure they DO protect.

UL Testing

If a manufacturer wants an Underwriters Laboratories (UL) label on their insulated records protection equipment, the product must meet or exceed the UL 72 testing standards.

Products may undergo four different fire resistance tests:

  1. Fire Endurance Test
  2. Fire and Impact Test
  3. Explosion Hazard Test
  4. Combined Explosion and Impact Test.

Primary records consist of many types of documents - paper records, microfilm, computer media, etc. Each has a different degree of tolerance to temperature, humidity and length of time exposed to harmful elements. To allow for these differences, UL tests cover three different temperatures and five different time durations.

The temperature noted on the UL label is the maximum temperature allowed inside the fire protective product during the test. For example, if the temperature inside a safe or file exceeds 176°C, it will fail the UL test for paper rated products. For tapes, cartridges, microfiche, and microfilm, the limit is 65°C (with an 85% humidity restriction); for diskettes, the temperature cannot exceed 52°C (with an 80% humidity restriction).

The time noted on the UL label indicates how long the fire resistant product was tested to withstand exposure to extreme temperature and still maintain a safe temperature/humidity level inside. The time lengths and temperatures for the classifications are:

CLASS A 4 hours 1093 degrees celsius
CLASS B 2 hours 1010 degrees celsius 
CLASS C 1 hour 926 degrees celsius
CLASS D 1 hour 926 degrees celsius
CLASS E 30 minutes 943 degrees celsius

Fire Endurance Test

Contents, which may consist of paper, computer media, or both, are distributed loosely throughout the fire resistant product to be tested. For products testing to meet the Class 150 or 125 requirements, the product is first conditioned for at least twelve hours prior to the test. Depending upon the classification time being tested, the furnace heat rises at a carefully monitored rate until the specified temperature is reached. Great care is taken to make sure the furnace heat is distributed evenly over the exposed surfaces of the products.

The following chart gives the temperature and time durations:

Time in Minutes Celsius Fahrenheit
5 538 1000
10 704 1300
15 760 1400
20 793 1460
25 821 1510
30 843 1550
35 860 1580
40 877 1610
45 893 1640
50 904 1660
55 916 1680
60 927 1700
90 977 1790
105 993 1820
120 1010 1850
135 1021 1870
150 1038 1890
165 1044 1910
180 1052 1920
195 1060 1940
210 1071 1960
225 1082 1980
240 1093 2000


After the temperature and time is reached, for example on hour - 927°C, the furnace is turned off. The test product must then cool in the unopened furnace until a significant decrease in the internal temperature is noted. This cooling process can take as long as 68 hours. During this cooling period, the tested product continues to absorb the heat in the furnace and the interior temperature of the product can continue to rise rapidly. It is during this critical point of the test that many manufacturers fail the test, particularly at the 52°C 80% humidity level. Only products whose internal temperature and humidity level remains below the test limits during the entire heating and cooling processes are awarded the label, the product is opened and examined to determine whether the contents are still in usable condition. The interior walls and components are checked for any evidence of heat or humidity damage.

One year after this initial test has been conducted; a sample product may be pulled out of production for retesting. The product must once again pass the original classification it was tested for to keep its UL label.

Fire and Impact Test

After a product has passed the Fire Endurance Test, another sample of the same product may be tested for fire and impact. The sample is prepared in the same manner as the Fire Endurance Test. Then it is heated to a specific time and temperature (see chart below). After the product has been exposed for the correct time period, it is immediately removed from the furnace and hoisted 30 feet off the ground. UL then drops the product within two minutes into a pile of broken brick on a concrete base. This is equivalent to a fall from a third story.

After the impact, the unit is carefully examined for any signs of rupture of insulation or parts, or openings into the interior of the product. Because products do not always land right-side-up in real life situations, the product is turned upside down after cooling. The product is then reheated to check exposure to heat, based on the following classification chart:

Classification Initial Exposure
Reheat Times
Oven Temp
350º -4 hours 60 Min 77ºC
150º -4 hours 60 Min 77ºC
125º -4 hours 60 Min 77ºC
350º -3 hours 60 Min 965ºC
150º -3 hours 60 Min 965ºC
125º -3 hours 60 Min 965ºC
350º -2 hours 45 Min 894ºC
150º -2 hours 45 Min 894ºC
125º -2 hours 45 Min 894ºC
350º -1 hour 30 Min 844ºC
150º -1 hour 30 Min 844ºC
125º -1 hour 30 Min 844ºC
350º -½ hour 20 Min 794ºC
150º -½ hour 20 Min 794ºC
125º -½ hour 20 Min 794ºC


Once the product has re-cooled, it is opened and dismantled. The testers examine the insulation material, the condition of the finish on the inside, the fastenings between parts, the security of interior equipment, locks, and the usability of the contents. Evidence of heat and moisture are also checked. One year later, UL may repeat this test on an identical product pulled from the production line.

The Explosion Test

All UL classified insulated record protection equipment must pass the explosion test. For this test, the sample is prepared in the same manner as for the two previous tests. The test furnace is left empty and heated to 1094°C. The testers quickly open the door and insert the sample. For 30 minutes (20 minutes for units rated ½ hour), the furnace is kept at 1094°C. If no explosion takes place, the sample remains in the furnace until it cools sufficiently to handle.

The sample is then forced to open and examined for heat or moisture damage. The interior finish, insulation, security or interior equipment, locks and fastening between parts, all undergo detailed inspection.

At the option of the manufacturer, the Impact and Explosion tests can be combined. The sample is inserted in the furnace to test for explosion, and then dropped 30 feet. The sample is then reheated and cooled again, and finally, examined carefully.

Sample Classification Labels

# 1 Label Style Record Protection Equipment
Classified By
Underwriters Laboratories, Inc
As to Fire Resistance
Rating:  Class ______ - ___ Hr
#2 Label Style Record Protection Equipment
Classified By
Underwriters Laboratories, Inc
As to Fire Resistance
Rating:  Class ______ - ___ Hr
See Marking Inside Unit for Class Ratings Applicable to Individual Compartments


Class or classes to be 350º, 150º, 125º Hr to be ½, 1, 2, 3 or 4.