TABLE OF CONTENTS For quantitative estimation of fire risks, reliable ignition frequency derived from fire statistics is a prerequisite. Annual ignition frequency obviously depends on the type of building. The average annual ignition frequency is the probability of a building catching fire per unit of floor area (measured in square metres) per annum. Average ignition frequency for three European locations and different building categories is given in Table 8.1
| London 1996 1999 | Switzerland 1986 1995 | Finland 1996 2001 | |
|---|---|---|---|
| Industrial and storage | 6.9 | 11.1 | |
| Shop and commercial | 22.0 | 6.6 | |
| Office | 5.3 | 2.5 | |
| Dwellings | 33.3 | 6.3 | |
| Public office | 10.6 | 4.7 | |
| Industrial | 11.6 | 9.6 | |
| All | 32.3 | 9.0 |
It has been known for some time [52,53] that within each building category ignition frequency also depends on the floor area of the building. Let f ( A) represent the average annual probability of a fire starting in a building in the category under study with area A, per unit area. Ramachandran [53] argued that since probability of a fire starting depends on the amount and nature of the ignition sources, and since the number of these sources increases with the area of the building, f ( A) is primarily a function of...
