Battery Rooms

[rlw]

Someone recently asked me about whether battery storage rooms were considered hazardous locations. The room in question was in a maintenance building where they were going to store spare vehicle batteries. I seem to remember somewhere in either the NEC or one of the other codes that the hazardous location requirement could be avoided if the space had a certain number of air changes per hour (I thought it was 6). However, I can't find any reference to this allowance in any code. Can anyone point me in the right direction if the code reference for # of air changes per hour exists?

 

[ron]

Re: Battery Rooms

I would think that the required number of air changes pertains to the particular gas and its properties.
Battery charging emits hydrogen. Considering the buildup of hydrogen and the concentration prior to toxicity and the volume of the room, you can calculate the # of air changes required.
If there is a rule of thumb or code minimum, I am not familiar with it.

 

[hurk27]

Re: Battery Rooms

Stored battery's do not produce anything unless they are ether being charged or discharged.

 

[hurk27]

Re: Battery Rooms

I forgot.
Look at 2002 NEC artical 480
480.9 A) Ventilation. Provisions shall be made for sufficient diffusion and ventilation of the gases from the battery to prevent the accumulation of an explosive mixture.

That's all it says

 

[jlb]

Re: Battery Rooms

The document that mentions the 6 air changes per hour is the NFPA 497. It is located in the definitions section (1-3)under "adequate ventilation" and section (3-3) "unclassified areas".