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

External fire alarm bell (or water motor gong)

External fire alarm bell (or water motor gong)

External fire alarm bell (or water motor gong)

I have had several customers ove rthe past few years ask me to show them in NFPA where it states that an external water motor gong or electronic fire alarm bell is required.

It just happened again!

If a water-based fire protection system has an electronic water flow switch with interior building alarms........is there a requirement for an exterior alarm device??

If so, where is this stated in NFPA??

RE: External fire alarm bell (or water motor gong)


Back in the origins of fire protection systems it was required to have outside annunciation due to the lack of central station systems and because in the event of a fire if the building was unoccupied at least you would have some sort of annunciation to the outside world since the streets will always have traffic.
Then they came up with a combination of game-well boxes on the streets. I know this requirement is somewhere on the NFPA 72 or NFPA 13. I will look into this after dinner. LOL

RE: External fire alarm bell (or water motor gong)

NFPA 13 2010ed. "An alarm unit SHALL include a listed mechanical alarm, horn or siren, or a listed electric bell speaker, horn or siren."

From that, we know that a bell is required somewhere on the premises.

A6.3.9.1 "Audible alarms are normally located on the outside of the building.  Listed electric gongs, bells, horns or sirens inside the building, or a combination of such used inside and out, are sometimes advisable.  Outside alarms might not be necessary where the sprinkler system is used as part of a central station, auxilliary, remote station, or proprietary signaling fire alarm system, utilizing listed audible inside alarm devices.

The commentary from the 13 handbook states "The audible local alarm required by can either be mechanically or electrically operated.  NFPA 13 does not stipulate whether the alarm's location is to be indoors or outdoors, since the location depends on site specific conditions.

Clear as mud? backs by stating "A local waterflow alarm shall be provided on every sprinkler system having more than 20 sprinklers.

So the answer to your question would be, no, there is not a requirement for an EXTERIOR water flow device.

Unless of course you're talking high rises, where we would apply ...The annunciator or register shall be located at grade level at the normal point of fire department access, at a constantly attended building security control center, or at both locations.

I've always shown an exterior bell on my plans, right above the FDC.  If the building owner doesn't want it there, or the sparkies don't want to run more conduit, I'm happy to put it anywhere suitable to the AHJ.

RE: External fire alarm bell (or water motor gong)

I would say if you are working in an ahj, start with the fire/ building code, because that may have annunciation requirements to point out to customers

Seems sometimes when you say because the ahj requires it, that helps  

RE: External fire alarm bell (or water motor gong)

Keep forgetting about this site.

The requirements for "exterior" for water flow alarm notification appliances comes from the Building Code for new systems and the Fire Code for existing installations.  The exact location may be specific for each jurisdiction but the code(s) just says one must be provided on the building's exterior in an area approved by AHJ or something to that effect.

"Fire suppression is a failure in prevention"

RE: External fire alarm bell (or water motor gong)

Here is an exerpt from the International Fire Code, 2009 edition:

903.4.2 Alarms. Approved audible devices shall be connected
to every automatic sprinkler system. Such sprinklerwater-flow
alarm devices shall be activated by water flow equivalent to the
flowof a single sprinkler of the smallest orifice size installed in
the system. Alarm devices shall be provided on the exterior of
the building in an approved location. Where a fire alarm system
is installed, actuation of the automatic sprinkler system shall
actuate the building fire alarm system.

As an AHJ, I require horn/strobes on the exterior of the building, in addition to the interior alarm system.  The horn/strobe is specified because firefighters now wear head phones while responding to incidents.  This is especially beneficial when responding to strip malls with multiple fire systems.

RE: External fire alarm bell (or water motor gong)


This is exactly what I have been looking for; however, I cannot find this excerpt (I cannot even find Section 903.4.2) in NFPA 1 or NFPA 101.

Where am I making my mistake here??  Thanks

RE: External fire alarm bell (or water motor gong)

Should be in the sprinkler section of nfpa 1

Under monitoring or notification or similar titled section

Do not have the book today

RE: External fire alarm bell (or water motor gong)

But once again you need to find what fire code is in use in the ahj you are working in!!!!!!!

RE: External fire alarm bell (or water motor gong)

I am aware of the applicable NFPA documents for our region (based on the current state laws); however, I simply cannot find the excerpt/verbage which byrnesf posted........I am fairly certain it exists, because it looks like a "cut & paste"! I just wish I could find the text he posted in code. You can get yourself into significant trouble basing your decisions on text posted on the internet.

Thanks to everyone out there!

RE: External fire alarm bell (or water motor gong)

He quoted out of the 2009 international fire code

RE: External fire alarm bell (or water motor gong)

I found the text.......finally.

Thanks to byrnesf & cdafd.

I simply do not understand WHY this statement or text is not included in NFPA 1, NFPA 101, NFPA 13 or NFPA 72!!!!

I hope everyone has a great weekend!


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


Low-Volume Rapid Injection Molding With 3D Printed Molds
Learn methods and guidelines for using stereolithography (SLA) 3D printed molds in the injection molding process to lower costs and lead time. Discover how this hybrid manufacturing process enables on-demand mold fabrication to quickly produce small batches of thermoplastic parts. Download Now
Design for Additive Manufacturing (DfAM)
Examine how the principles of DfAM upend many of the long-standing rules around manufacturability - allowing engineers and designers to place a part’s function at the center of their design considerations. Download Now
Taking Control of Engineering Documents
This ebook covers tips for creating and managing workflows, security best practices and protection of intellectual property, Cloud vs. on-premise software solutions, CAD file management, compliance, and more. Download Now

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