ISO 834 Standard Fire

The fire (time-temperature) curve used to define the furnace temperature in BS ISO 834-1 1 tests. The ISO 834 series specifies a test method for determining the fire resistance of various elements of construction when subjected to the time dependent temperature conditions.

The standard fire curve is defined in Equation (22) (Clause 6.1.1, ISO 834-1).

(22)\[T=345\log_{10}\left(8t+1\right)+20\]

where

\(T\) is the average furnace temperature, in degrees Celsius;
\(t\) is the time, in minutes.

Fig. 6 shows the standard fire curve derived based on Equation (22).

Standard time/temperature curve

Fig. 6 Standard time/temperature curve (1 is the standard time-temperature curve, source: Figure 7, ISO 834-1)

1

BSI, BS ISO 834-1:1999 Fire resistance tests. Elements of building construction. General requirements., BSI, London, Sep. 1991.