Water Mist Suppression System Replacement

The Water Mist Suppression and Sprinkler Systems requirement is for the procurement of a principal contractor to remove, replace and commission the Water Mist Suppression and Sprinkler Systems currently installed in 34 locations situated within 22 different London Underground stations. TfL's has identified that the fire suppression and sprinkler systems currently installed in the sites (Cleaner's Stores, Bin Stores, Stores and Retail Tenancies) are either life-expired, non-compliant or not fit for purpose under Article 5 of the Fire Precautions Sub-surface Railway Regulations 2009.

It has also been identified that these systems do not have / meet the current applicable standards such as BS EN14279 and BS8489. The water mist systems have been installed on the TfL infrastructure in the early 1990's following the publication of the Fire Precautions Sub-surface Railway Regulations 1989 (updated 2009).

The systems were installed where conventional sprinkler systems were not considered viable due to practical or logistical constraints and designed, installed and maintained in compliance with the American Standard NFPA750. Due to the increasing number, sizes, type of storage and trading activities within the network, further review of risks and tests for these suppression protection systems were undertaken and evaluated.

This confirmed a requirement to replace these systems and design modern, compliant equivalent water mist system to replace the ageing noncompliant systems currently installed in the TfL LU estate. The modern systems will be tested by TfL to BS EN 14972-1 Annex A with a deluge time of not less than 60 minutes from the appropriate number of cylinders located locally, to provide reliable fire suppression to specific rooms identified.

These new installations will be designed for but not limited to Cleaner's Stores, Bin Stores, Stores and Tenancies. In some cases, wet sprinklers systems extensions will replace the ageing Water Mist systems where they are available and economically viable.