Would you do it? Why?

Hello all,

As per EN54/NFPA, what’s your opinion on if fire detection system should be installed in this area on the platform where it’s open from both sides but the roof is covered.

Also, if you can notice, there are many deep cross beams on the ceiling which would require several detectors to cover each fire partition. Beam detection could also be an option but with several metal obstructions, it would be a little tricky. The platform area is about 150-180m in length.

I would really appreciate if you could provide your technical reasons, reference to any standards or best engineering practices.

Beam detectors might be possible if installed next to the ceiling without any wires or pipes getting in the way. Although I’d say heat detectors would work best out there since it’s in an open space.

Really appreciate your input Kai. Do you think there is a technical requirement based on EN54 or NFPA and if so I would appreciate if you could help me find a relevant clause.

I would highly suggest you contact your local AHJ or engineer if this is regarding a real project… Not many of us have expertise in this field.

NFPA 130 is the standard that addresses life safety matters for a train station. 5.4.2 addresses fire detection:

5.4.2.2* Automatic fire detection shall be provided in enclosed stations and enclosed areas of open stations except in the following:
(1) Areas used for public circulation
(2) Trainways within stations
(3) Areas protected by an automatic fire suppression system that initiates a fire alarm signal upon activation

The annex of a section addressing automatic fire sprinkler systems describes “public circulation areas” as concourses (mezzanines), platforms, and stairs and escalators for public use. This is provided that all other requirements are followed in NFPA 130, which also restricts the type of construction and interior finishes such that it’s considered unnecessary to have a fire sprinkler system. However, you must consider the actual contents of the space – the code stipulates the minimum acceptable requirements if everything in the code is followed at the same time. Depending on what a client needs, this can be unrealistic.

Both spot type and beam detection will have their advantages and disadvantages, but I can see both working in this case. If a fire sprinkler system is required, it may be more cost-effective to go with that instead.