fire storage calculation

[cranstonbu]

I am in a process to size a fire storage tank for a camp site. the site is 800 man. no idea how to size a tank for fire water by the code. any info. is welcome. Thanks.

 

[LCREP]

As per NFPA 13, 2010 ED

Sprinkler demand (GPM) x hose demand (GPM) = GPM x (duration/time)= TANK size.

NFPA 13 duration as follows: light hazard 30-60 minutes, ordinary hazard 60-90 minutes, extra hazard 90-120 minutes

11.2.2.5 The lower duration value of Table 11.2.2.1 shall be acceptable only where the sprinkler system waterflow alarm device(s) and supervisory device(s) are electrically supervised and such supervision is monitored at an approved, constantly attended location.

****************************************
Fire Sprinklers Save Firefighters’ Lives Too!

 

[LCREP]

Opps

Sprinkler demand (GPM) x hose demand (GPM) = GPM x (duration/time)= TANK size.

Sprinkler demand (GPM) PLUS hose demand (GPM) = Total GPM x (duration/time)= TANK size.

****************************************
Fire Sprinklers Save Firefighters’ Lives Too!

 

[cranstonbu]

Can you explain more? I am new to this area. how can I know the sprinkler and hose demand from a camp site? and how to decide light, ordinary and extra hazard? thanks.

 

[cdafd]

Are you just trying to size for fire hydrants only??

Or will some/all have fire sprinkler systems??

How many buildings

What size is each one??

 

[MGXFP]

You might also check ISO or other insurance requirements for this particular instance to find fire flow. If there are buildings present then you can get a guess for how much water is required using the ISO calculation to protect the buildings.

It seems you're looking for fire flow which is different than sprinkler demand.

Are you looking to size for wildfire conditions? We really need more information.

 

[cranstonbu]

This is a camp site for an oil company. There will be dorms for workers to live in. The water will be connected to hose cabinets at the dorms. Not sure this fire flow should be calculated based on population or building sizes or something else?

 

[cdafd]

Should have asked any city, county, state, fire district that has jurisdiction over the camp?

As in they might dictate water demand

If not maybe get with the fire dept that would respond to the camp and see what they need

Sounds like it should be based on building size

Will there be some type of pump involved??

 

[SprinklerDesigner2]

Doesn't sound like the "camp" is in the USA.

 

[DavidCR]

I suggest you consult an expert of course, but I understand that sometimes you are forced to make some special, desperate, non standard considerations, so, consider the following to give you an idea, hope this helps you to improove your criteria.

If you have not a NFPA13 sprinkler or NFPA 14 water demand and you are not in US, and you have don´t have an authority to define it....

1. NFPA1, Appendix H. Includes a table that defines fire flow(gpm) and durations (hrs) based on type of construction (non combustible, combustible, etc, based on NFPA 220). The minimum is 1500gpm for 2 hrs. This table will lead you to a huge tank, so this table is criticized and is not part of the standard. I´ d use this table if the risk is worth it.

2. Ask fire brigade. The would tell you that the minimum is to operate a mobile equipment for some time. In my country (Costa Rica) it would be 57m3, and they ask for it for installations of 2500m2 and above, when it is not feasible to use NFPA.

3. NFPA 14 has it´s rules that should be applied by experts, but approximately consider that if you need Class II connections (1-1/2 NH), the minimum is two 100gpm hoses working simultaneously, if you need Class I connections (2-1/2 NH), the minimum is two 250gpm hoses working simultaneously, you may have an idea of the water you need if you define a working time, from 0.5hr to 2hrs.

4. There is an old aprox. method, considering area of exposed building with 0.1 to 0.16 gpm/ft2 of water, you define working time for 0.5hr, 1hr, 2hr. So you asume some exposed area. 0.1gpm/ft2 is a flow enough to cool surfaces exposed to fire.

Of course If an expert designs a NFPA 13 building, you will need less water.

 

[786392]

Dear,

Even FM (Factory Mutual) can be very helpful; try it by registering using your email ID, I believe.

Best Regards
Qalander(Chem)