Different K-Factors for Duct vs Paint Spray Booth?

9/19/2024

Can you use a different k-factor for sprinklers in a duct and plenum versus the k-factor for the booth sprinklers in a paint spray booth?

I was told I could not use different k-factors to calculate the hazard. Thanks in advance.

Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe

6 Comments

Pete H

9/19/2024 06:47:18 am

I could be wrong, but I don't see why not. Especially if you include heads at both their respective K factors in your calculation area/calcs or provide two calcs.

That stated, I could be wrong and there could be an item of code that requires these to be the same. It's not something I'm overly familiar with.

Dan Wilder

9/19/2024 08:00:32 am

Different areas, different design approaches.

Ideally keeping them the same would be the best however I've used larger K-Factor sprinklers in the booth and smaller in the attached ductwork without any issues.

Also, as "Spray Applications" and "Ducts" carry separate design criteria (26.4) this furthers the "Special Use" example.

13-2019
27.2.4.9.3
Sprinklers with different K-factors shall be acceptable for special use such as exposure protection, small rooms or enclosures, or directional discharge.

Franck

9/19/2024 08:12:03 am

I don't see a technical reason for that.
As indicated above, these are 2 different areas.
In addition, sprinklers in the duct may have different temperature rating and may be of different type as in some environment, they may need to be wax coated (when corrosive atmosphere are being trasnfered inside the ducts, such as for surface and chemical treatment plants).

Chris Nelson

9/19/2024 08:26:30 am

I would argue as long as you get that 30 GPM per head per NFPA 33, you're good!

Jesse

9/19/2024 10:08:36 am

While you can't use sprinklers with different K-factors in a design area for the purpose of making the systenm calculate, you different design areas with different design criteria. You should be ok.

Jack G

9/19/2024 04:08:49 pm

Agree. Different areas.
Just 30 gpm at 30 psi required. Watch your end head pressures.

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.

Different K-Factors for Duct vs Paint Spray Booth?

Leave a Reply.

ALL-ACCESS

SUBSCRIBE

COMMUNITY

YOUR POST

PE EXAM

FILTERS

ARCHIVES

PE PREP SERIES