Reliability of sprinkler system in Australian high rise office buildings

• A comprehensive fault tree analysis (FTA) for wet pipe sprinkler systems typically used in Australia has been developed.
• A physical survey was conducted to collect data for determining the reliability of various components of a sprinkler system.
• Developed FTA has been used to estimate the sprinkler system reliability based on both survey and literature data.
• The sprinkler system reliability estimated using FTA has been compared with US and Australian statistical data.
• A number of suggestions has been made to improve the reliability of sprinkler systems.

A comprehensive survey of sprinkler systems in high-rise office buildings was carried out to determine the reliability of various components of such systems in Australia. Based on the survey data, a fault tree analysis (FTA) has been used to estimate the overall reliability of these sprinkler systems. Data from 26 buildings were collected and are presented in this paper. In addition, data from overseas surveys has also been considered based on their relevance to the office buildings. The analyses are confined only to wet-pipe systems, as these constitute the vast majority of automatic sprinkler systems in Australia and New Zealand. To develop the fault trees, the designs found in usual practice are considered, rather than the designs just complying the Australian codes with the minimum requirements. A range of reliability for the sprinkler systems is estimated based on a number of considerations. Sprinkler zone shut off during tenancy changes and out of specification sprinkler head appear to be the main factors that may lead to a sprinkler system failure.