Refill Considered When Sizing Fire Water Tank?

11/17/2020

Is it permissible to consider the refill supply for a water storage tank when sizing the tank?

The supply would come in above 20 psi. Thanks in advance.

Posted anonymously for discussion. Discuss This | Submit Your Question | Subscribe

10 Comments

Dave Branson

11/17/2020 10:13:59 am

Yep. This is basically a minima-maxima problem - the outs minus the ins.

Glenn Warga

11/17/2020 10:25:53 am

See Break Tank calculation formula. 20 psi must be maintained at selected refill rate.

Logan Nootbaar

1/17/2023 09:04:43 am

What is this formula

James Phifer

11/17/2020 10:54:24 am

From NFPA 22:
4.1.4 A tank shall be sized so that the stored supply plus reliable
automatic refill shall be sufficient to meet the demand
placed upon it for the design duration.

Fred

11/17/2020 05:59:36 pm

Are water tanks that meet required amount required to be autofilled or is manual filling permitted.

Franck

11/18/2020 04:51:41 am

For a break tank, automatic refill is mandatory (for obvious reasons).

For other tanks with the full required capacity, automatic refill is not mandatory per NFPA.

The only requirements are :
4.2.1.4
The water supply shall be capable of filling the minimum required fire protection volume within the tank in a maximum of 8 hours.

14.4.1
A permanent pipe connected to a water supply shall be provided to fill the tank, except as provided in 14.4.1.1.

14.4.1.1
Where a permanent water supply is not available to refill the tank, an approved plan shall be permitted for manually refilling the tank.

14.4.3
The tank shall be kept filled, and the water level shall never be more than 4 in. (102 mm) below the designated fire service level.

It is normally recommended to provide a low water level alarm so as to know when the level is drooping so that you can refill manually the tank.

Fred

11/18/2020 06:13:30 am

Franck, thanks great points. I think as per 14.1.8 a water level gauge of some sort should be provided on a regular tank as well.

Martin Etcheverry

7/17/2024 11:24:34 pm

Regarding the Refill flow, is there any statement Regarding the pumping system requirements?? Using an infnite source as may be a lake or river, installing a vertical turbine pump, should it require to be listed?? That pump, as it is not strictly a Fire Pump as it will Work with low pressure flow. Is there any specific restriction Regarding the refill pumping system under NFPA22 or NFPA20?
Thank you very much

Franck

11/18/2020 04:55:26 am

The only requirement when using a break tank is that the tank capacity is at least sized for a minimum duration of 15 minutes with the fire pump operating at 150 percent of rated capacity.

Break tanks are often used in Europe when there is no authorization to connect the pump directly on the city water supply (for possible pollution from water in the sprinkler system towards the potable city water system).

red

6/25/2021 09:37:43 am

How do you calculate the city water refill rate into the tank? Is there a program and or formula?

Leave a Reply.

Home
Our Cause

The Blog
The Forum

PE Exam Prep
The Toolkit
MeyerFire University

Pricing
Login
Support
Contact Us

MeyerFire.com is a startup community built to help fire protection professionals shine.
Our goal is to improve fire protection practices worldwide. We promote the industry by creating helpful tools and resources, and by bringing together industry professionals to share their expertise.

MeyerFire, LLC is a NICET Recognized Training Provider and International Code Council Preferred Education Provider.
All text, images, and media Copyright © 2016-2024 MeyerFire, LLC

We respect your privacy and personal data. See our Privacy Policy and Terms of Service. The views, opinions, and information found on this site represent solely the author and do not represent the opinions of any other party, nor does the presented material assume responsibility for its use. Fire protection and life safety systems constitute a critical component for public health and safety and you should consult with a licensed professional for proper design and code adherence.

Discussions are solely for the purpose of peer review and the exchange of ideas. All comments are reviewed. Comments which do not contribute, are not relevant, are spam, or are disrespectful in nature may be removed. Information presented and opinions expressed should not be relied upon as a replacement for consulting services. Some (not all) outbound links on this website, such as Amazon links, are affiliate-based where we receive a small commission for orders placed elsewhere.

Refill Considered When Sizing Fire Water Tank?

Leave a Reply.

ALL-ACCESS

SUBSCRIBE

COMMUNITY

YOUR POST

PE EXAM

FILTERS

ARCHIVES

PE PREP SERIES