Borough Station - Replacement Fire Main

As part of a Borough station upgrade on behalf of Transport for London (TfL), TfL’s Lift & Escalator Department was onsite replacing two existing Primary Means of Vertical Transportation (PMVT) lifts. Whilst carrying out these works, it was noted by the specialist lift contractor that the existing fire main installation was non-compliant with EN81-73 2020 Safety Rules for the Construction & Installation of Lifts.

As a result, the fire main had to be removed/taken out of service and rerouted from the lift shaft entirely. After further investigation by TfL Fire engineers, it was identified that the existing Dry Falling Main serving the station did not comply with current rules and regulations.

Requirement

Fire mains are provided in buildings to ensure firefighting water supplies can be provided from the outside of the building to various strategic locations within the building.

L.B. Foster was employed to carry out the design and installation of a new fire main, ensuring it complied with the requirements of LU S1082 Active Fire Systems & Portable Fire Fighting Equipment, as well as BS9990 Non-Automatic Fire Systems in Buildings.

The type of Charged Dry Falling Main that was installed onsite at Borough by L.B. Foster was the first of its kind on a TfL station.

The scope of works included:

• Decommission and removal of existing non-compliant fire main within Station Lift Shaft
• Survey and design of a new dry falling main in accordance with BS9990 – 2015
• Installation and commissioning of the system with Bespoke testing plan and specialist pumping equipment.
• Design and installation of one of a kind fireproof scaffold within station spiral stairs
• Design, manufacture, and installation of bespoke fire hydrant cabinets
• Design and fabrication of welded piping arrangements
• All associated builders work inclusive of making good, tiling, and cutting and forming of new openings.
• Fire stopping of new openings

Our Solution

L.B. Foster worked with Transport for London and Borough station to design, install and commission the new Charged Dry Falling Main, which requires water supplies from the attending fire authority. Within tall buildings, up to 50m high, most complex buildings and buildings incorporating deep basements, the fire mains will be in the form of a dry riser (or dry falling main with respect to basements, as in the case of London Underground). This proved a challenging task due to the route the pipework had to take, and in addition, some of the issues that came to light during the project were limited space, multi-levels of concrete poured tunnels, locations of existing assets, and the locations where the hydrants had to be installed.

The type of Charged Dry Falling Main that was installed onsite at Borough by L.B. Foster was the first of its kind on a TfL station because of the route the pipework had to take onsite. The pipework was predominantly on show/exposed to the public throughout the low levels of the station. The decision was made at design stage to propose the use of stainless-steel pipework and fittings, which proved to be a great success and has set a precedent going forward for all future TfL sites.

A specialist scaffolding company was subcontracted by L.B. Foster to design and erect a bespoke scaffold with fireproof boards within the internal spirals of the station’s staircase. This allowed safe access for the team on site to install the fire main and bespoke bracketry.

The station was closed to members of the public for the entirety of the Project/Upgrade with a short deadline/window to complete the works which were achieved, allowing the station to open with a new fully commissioned fire main inclusive of:

• new stainless-steel pipework
• fittings
• dual pressure relief outlets
• breeching inlet valve
• isolation valves
• fire signage
• bespoke bracketry.