NFPA 13 - Sprinklers

[kurnal]

Come across an NFPA 13 sprinkler installation for the first time in a warehouse setting (Belgium). It has a single diesel pump supply.

From a  quick look at NFPA 13 a single pump installed to NFPA 20 is acceptable as a sole source of supply. Have I missed something? It begs the question what happens if it breaks down?

Is a single pump typical for NFPA installations? Is it generally accepted as an equivalent standard to FMG and LPC systems outside the USA?

[AnthonyB]

I've cross posted this on a FB sprinkler group that has a few US based sprinkler engineers on it and will put any replies on here.

[kurnal]

Thanks Anthony

[AnthonyB]

Hi, got the following back:


"A single main pump is acceptable for most applications.

Multiple pumps are used mainly on very large high rises where one pump would be insufficient, and often they are set up to supply different zones, depending on pump capacities and required pressure.

All systems will have a jockey pump, which is a small electric pump that is independent of the main pump. It's job is to maintain pressure from slight fluctuations without firing up the main pump.

In the event of s pump failure, there is a main line bypass that can be manually opened to completely bypass the pump and use city pressure. Not ideal, but better than nothing. The theory is that with proper maintenance and fast fire dept. response, the pump should only be running and supplying full pressure for a short time.

Once the fire apparatus arrive, they will do the majority of the pumping.

I honestly have never seen a building with multiple fire pumps, so in my experience, I would say that yes, a single pump is the most common."

[kurnal]

Thanks Anthony. The bit about "main line bypass" says it all. This implies there would normally two sources of supply, the public mains and the single pump. It goes on to suggest the fire service would augment the supply on arrival.

In the installation I refer to there is no "main line bypass". Just a suction tank and a single pump allegedly compliant with NFPA codes. Perhaps  it is  compliant with the letter but not compliant with the spirit. And perhaps it would not therefore be acceptable in the USA.

I have recommended that as they are extending the warehouse they should take the opportunity to rectify this deficiency by installing a duplicate 100% duty pump. They did not like it but I think I will stick to my guns.

In its present configuration it certainly would not be compliant with FMG or LPCB standards!  

[AnthonyB]

Apparently there should be a Fire Department Connection on all the NFPA compliant systems, I've asked what you set up would comply with - I'd agree that if extending they should try to make the system more compliant.