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ISO 9705


The method follows procedure given in international standard ISO 9705:1993(E), and in NORDTEST method NT FIRE 025/ISO 9705:1993.

The room/corner test is an advanced large scale method for assessing materials reaction to fire. The test gives a possibility to evaluate

  • surface flame spread
  • smoke production
  • production of toxic gases


The side walls, the rear wall and the ceiling of a test room with length 3.6 m, height 2.4 m and width 2.4 m are covered by the surface material to be tested, i.e. a total amount of 32 m2 surface material is needed. The ignition source is a propane burner placed in one of the rear corners, and the heat output is 100 kW for the first 10 minutes, and 300 kW for the next 10 minutes. Total testing time is 20 minutes. Combustion gases are collected during the test by an exhaust hood for further analysis. This gas analysis makes it possible to calculate heat release rate and to assess production of toxic gases from the specimen. Smoke production is assessed by measuring attenuation of a light beam by smoke in the exhaust duct. The attenuation is related to volume flow, resulting in a quantification of smoke density called smoke extinction area [m2/s].


The test report contains information about dimensions, pretreatment and mounting of the test specimens, and information about the test conditions. The following test results are tabulated:

  • Time to flashover [s]
  • Total heat released [MJ]
  • Maximum heat release rate [kW]
  • Average heat release rate [kW]
  • Maximum smoke production [m2/s]
  • Average smoke production [m2/s]
  • Total production of CO (carbonmonoxide) [g]
  • Total production of HCN (cyanic acid) [g]

The following results are given graphically:

  • Heat release rate as a function of time [kW]
  • Rate of smoke production [m2/s]
  • Rate of CO-production [g/s]
  • Rate of CO2-production [g/s]
  • Rate of HCN-production [g/s]
  • Heat flux to the center of the compartment floor [kW/m2]
  • Mass flow in exhaust duct as a function of time [kg/s]


Criteria for test results are given in Melding HO-1/94: Plast i bygninger from the National Office of Building Technology and Administration (BE). The criteria are as follows:

Class Minimum time to flashover [min] Heat release rate (burner effect excluded) [kW] Rate of smoke production [m2/s] 
Maximum Average Maximum Average

ClassMinimun time to flashover
Heat Release Rate
(Burner effect exluded)
Rate of smoke production

The flames shall not spread further downwards than 0.5 m from the floor, except for the area within 1.2 m from the corner where the burner is placed. For materials of class A, only a few burning drops or burning pieces are allowed to fall down in the area 1.2 meters away from the corner where the burner is placed. Class A corresponds to properties for products classified as In1 according to Norwegian standard NS 3919. Class B-E correspond to properties for products classified as In2 according to Norwegian standard NS 3919.


The criteria below are given in IMO Res. MSC.40(64): Standard for qualifying marine materials for high speed craft as fire-restricting materials.

A surface material or lining is considered to be a " fire-restricting material" if during testing time of 20 min according to the standard ISO 9705 the following six criteria are fullfilled:

  1. The time average of HRR excluding the HRR from the burner does not 
    exceed 100 kW
  2. The maximum HRR excluding the HRR from the ignition source does not exceed 500 kW averaged over any 30 s period of time during the test
  3. The time average of the smoke production rate does not exceed 1.4 m2/s
  4. The maximum value of the smoke production rate does not exceed 8.3 m2/s averaged over any period of 60 s during the test
  5. Flame spread must not reach any further down the walls of the test room
  6. Than 0.5 m from the floor excluding the area which is within 1.2 m from the corner where the ignition source is located
  7. No flaming drops or debris of the test sample may reach the floor of the test room outside the area which is within 1.2 m from the corner where the ignition source is located.