Contact US

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Stationary Batteries Compartment Ventilation

Stationary Batteries Compartment Ventilation

Stationary Batteries Compartment Ventilation


Q1.Are there any code requirements for the ventilation of the battery compartment of Lead/Calcium flat plate Batteries, 120VDC (60 cells)?

If the answer to Q1 is YES:
Q2. Which code/article?
Q3. In layman's words, what are those requirements?

If the answer to Q1 is NO:
Q4. What would be an acceptable ventilation?

RE: Stationary Batteries Compartment Ventilation

I'm dealing with a similar project now.  Our ventilation was existing already so I didn't look for codes.  If you still interested, here's what I learned:  

The lower explosive limit for Hydrogen gas is 4% by volume.  Using a safety factor of 5, (to account for gas production fluctuations, room temp, deterioration of ventilation system) this reduces to 0.8% by volume.  Determine the H2 gas production rate.  Determine the time in which 0.8% H2 gas concentration is reached.  If, for example, it were 20 minutes, then at least one air change is needed per 20 minutes.  To determine the H2 gas production rate I used the following:  

(charging amperage) X (# of cells) X (.016 cubic feet  of H2 per hour-cell-amp)

RE: Stationary Batteries Compartment Ventilation

I'd suggest you should review is the National Fire Protection Agency
(NFPA) as well as any local fire codes.

NFPA/Codes/NFPA 100 - 199/
              - NFPA 111 Standard on Stored Electrical Energy Emergency and
             Standby Power Systems 2001 Edition/Appendix A Explanatory Material
             ... A.2.1.13 Uninterrupted Power Supply (UPS).   The UPS usually
             monitors and tracks ... as uninterruptible power supplies, ventilation
             where essential to maintain ... refrigeration systems, communication
             systems, ventilation and smoke removal systems ... due to corrosion, for
             ventilation requirements for hazardous gas ...  


RE: Stationary Batteries Compartment Ventilation

I am having trouble sourcing a vent or breather for a similar project that uses a lead-acid battery.  Does anyone have a link to a supplier for a passive vent or breather for a smaller electrical enclosure?

RE: Stationary Batteries Compartment Ventilation

Look at IEEE 484, there is a small section on ventilation.

RE: Stationary Batteries Compartment Ventilation

Suggestion: Check local and state building codes.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members! Already a Member? Login


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close