BS 8489 published as full standards. Understandably many organisations are still not familiar with these standards and look for guidance and advice on how to apply water mist for their particular application or risk. For those involved in imparting knowledge for water mist systems, it is time for water mist standards to be followed.
Design standards for sprinklers have been evolving since they were first written in the late 1800s. Since then, various organisations with risk management interests, have used rules such as BS EN 12845, LPS standards, British standards, American NFPA and FM standards which have developed continuously to the present day.
Previously in the absence of design and installation standards for water mist systems, specifiers have used NFPA750, EN 14972 and incorporating BS EN 12845 and BS 9251 automatic sprinkler standards within their specifications, as a coverall approach. But now that British Standards exist for water mist, the coverall approach is out-dated.
Water mist systems are usually compared to sprinkler systems, as they share three major parts; a water supply, an alarm system and a distribution system. This is where the similarities end. So, it is somewhat disappointing that water mist specifications still make reference to sprinkler standards. This can cause confusion for the customer, main contractor and the fire protection provider as to what system specifications are actually required.
The benefit about making reference to BS 8458 and BS 8489 within specifications is that the client can be assured of a fully designed and compliant system, with approved components successfully passed to fire test protocols. Specifications to these standards are proof to building control, insurers and the customer that the system meets the appropriate standards and has been installed correctly. To muddy the waters with confusing references to sprinkler and other standards may mean that a non-compliant system is ultimately installed.