Determining fire flow can be a tricky subject. This week I'm breaking down one common method of determining fire flow requirements and hopefully exposing some myths about the process.
Not an Exact Science
First, determining the exact amount of water required to manually suppress a fire is dependent upon so many variables. The amount of water used could depend on the building size, hazard, outdoor conditions, speed of fire growth, fire department response time, whether the building is protected by sprinklers, and on and on.
The methods used to calculate fire flow are different methods at estimating the amount of water required to manually suppress a fire. It is not an exact science.
What is Fire Flow?
I'll start by what fire flow is not. Fire Flow is not the volume of water required for the fire sprinkler system. I couldn't count the number of projects where Fire Flow has been assumed to be sprinkler-related.
Fire Flow is formally defined as the "flow rate of a water supply, measured at 20 psi (138 kPa), that is available for fire fighting." (IFC 200-2018 Appendix B Section B102)
Fire flow is used to determine the quality of a water supply to an area. It's used as an aid to determine pipe size and arrangements to delivery water to a specific area.
Fire Flow is important for emergency response at it is the total capacity of the system that the fire department has available for use in response to a fire.
How Is Required Fire Flow Determined?
In short - it depends.
There are many methods for determining fire flow. The most common cited in US circles include the Insurance Services Office (ISO) Method, Iowa State Method, and the Illinois Institute of Technology (IIT) Method. At least a dozen other methods exist (for more on these, the Fire Protection Research Foundation provides great analysis in Evaluation of Fire Flow Methodologies research paper).
The International Fire Code (IFC) offers Appendix material that provides guidance for determining the required fire flow, which is based on the ISO Method. It is not a mandated code requirement unless a jurisdiction adopts the Appendix.
Many jurisdictions I've worked with do not have an ordinance that adopts the appendix, but when asked they are typically open to using the IFC Appendix B method of determining fire flow. The International Fire Code, which is widely adopted in the US, only requires that an approved water supply "capable of supplying the required fire flow" be provided to buildings.
This process will be explored in more detail here.
1. Determine Baseline Fire Flow
The first step in this overall determination of water supply to a site is to determine the required fire flow.
Using the IFC Method, Appendix B has a reference table that stipulates a minimum fire flow and flow duration based upon building size and construction type (2000-2012 Table B105.1, 2015-2018 Table B105.1(2)).
2. Reductions & Increases
Once a baseline value for flow and duration is taken from the table, it can be reduced based on the presence of sprinkler system.
Section B105 details the adjustments that are available for buildings with a sprinkler system. A reduction of up to 75% can be permitted for buildings with a fire sprinkler system.
It's important to note that up through the 2012 edition of the International Fire Code, a reduction of fire flow had to be approved, meaning the AHJ must agree on the reduction. This may not make a difference if a jurisdiction hasn't adopted the appendix and the entire calculation has to be approved anyways, but in the case where Appendix B is adopted and you're under IFC 2000 through 2012, you'll need AHJ buy-in to use the reduction.
The 2015 and 2018 edition of IFC removed the approval necessity for sprinkler flow reductions.
As part of this process the Fire Chief is also authorized to decrease the required fire flow, based on building isolation or impracticality. Alternatively, the Fire Chief is also authorized to increase based on unusual susceptibility for the facility. These stipulations come with Section B103 of Appendix B (all editions).
Fire Flow is used to quantify the available water supply for manual firefighting operation.
3. Verify Provided Fire Flow
The best way to verify fire flow for a location is to conduct a flow test at the site itself. This of course can be difficult to impossible for new-construction projects on virgin sites.
For developed areas or building expansions, this may not be difficult to accomplish.
I have a current project we're working on that is a major building expansion. Fire flow needed to be assessed based on the new expanded building and whether a single 8-inch feed would still meet the minimum requirements. A flow test on the site itself confirmed that we are just short of required fire flow which prompted a healthy discussion with the AHJ.
4. Calculate from Flow Test to Site (if necessary)
Sometimes a flow test can't be conducted on the site itself.
When this is the case, a hydraulic calculation can be run between the water supply source (nearby flow test, a water tower, reservoir, or pump) and the project site to estimate what the available fire flow will be. This calculation incorporates the pressure loss of the pipe network as water is constricted between a source and a project site. The best way to confirm actual fire flow (in my opinion) is to verify with a flow test once any extension is installed.
Easy Tools for Fire Flow & Water Supply Analysis
There's a new tool in the arsenal around here that directly addresses fire flow requirements.
It's the Fire Flow Calculator that's now a part of the Toolkit. If you're already a Toolkit subscriber, download it today.
The Fire Flow Calculator uses the IFC method based on your project parameters to quickly grab the baseline fire flow and duration, and make adjustments for sprinkler protection. Now you have extremely quick access to determine required fire flow, and the documentation to support your process.
This is a tool I'm happy to debut and have used with great client feedback.
On a side note, Toolkit subscribers also now have access to last week's Design Checklist with user-provided feedback. The download update includes both tools. Give them a download and let me know what you think!
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If you've been following the blog for awhile, you might already know about the Toolkit that has really taken off lately. This past week I've incorporated some (great) user feedback and now have a new version to present:
I've revamped the organization and it's FAR easier to navigate and use now.
With a new main menu and crisp pages the Toolkit is FAR easier to navigate. Now you can get what you need, quickly.
If you're already a subscriber to the Toolkit, use the download link below to get the latest version right now. No need for any new access codes - it just updates the Toolkit right over your current version.
A clip of the latest version of the Sprinkler Obstruction Calculator on the MeyerFire Toolkit.
What is the Toolkit, and what does it include?
The MeyerFire Toolkit is a downloadable series of excel-based tools that allow fire protection designers, engineers and code authorities to quickly calculate a myriad of regular applications. With this tool you can save time with quick but powerful tools that you can save, PDF, or print.
The Toolkit contains all of the tools you see on this website - plus the popular Fire Sprinkler Database - which is a live collection of all fire sprinklers on the market where you can sort and filter to see what products exist for your application, and then specify or design the ones that best match your design goals.
A Free 30-Day Trial, Starting Today
If you've never seen the Toolkit, or have used a trial version before and are interested in testing the new look, download the toolkit with a trial code (good through late March) here:
There's a few new additions to the Toolkit I hope to debut in the next couple weeks based on suggestions from users just like you. If you're an expert in fire flow calculations or water storage tank design and are interested in early testing, email me at firstname.lastname@example.org.
If you know someone who might be interested in giving the Toolkit a try, email them about downloading it today. This free trial only lasts through late March 2019. As always, you can subscribe to these weekly articles & resources here.
I receive feedback regularly from many users and observers - and I'm very grateful for both!
Sprinkler Database Interest & Feedback
One member recently reached out about the Sprinkler Database and said:
"I appreciate all the work you’ve done on that site. The sprinkler database has helped tremendously when looking for specialty sprinklers, specifically available storage sprinkler is odd configurations!"
It's a tool that is basic in premise but can save tons of time when you're looking to compare sprinklers, find a specific type of sprinkler, or see if a solution exists for your specific problem. Here's a quick overview
Fire Pump Database
With the interest and feedback from the Sprinkler Database, it was only a matter of time before I expanded this into other areas. You may already have seen the Backflow Database, but now we have a beta version of a Fire Pump Database.
With the fire pump database you can now search for fire pumps of various configurations, drivers, sizes, and then instantly link to CAD and Revit models, performance curves, website links, product data, and dimensions. The current beta version includes AC, Armstrong, and Aurora Fire Pumps.
All-inclusive Toolkit members can log in and use the database now.
Know a Contact for Patterson or Peerless?
If you work for or know a great contact for Patterson Fire Pumps and Peerless Fire Pumps, please let me know their contact information. I'm looking to partner with both of these companies to also help connect users to their products.
Toolkit Sale Through November 30th
Interested in getting the Toolkit and access to all of our tools? Join between now and Friday the 30th for $30 off your first year's subscription. Just use coupon code CYBER18 when you checkout here before Friday November 30th.
Lastly, if you're in the US, I hope you have a great Thanksgiving!
Last week I introduced a new Thrust Block Calculator and explored some of the concepts around the design and function of Thrust Blocks.
Here's the new expanded thrust block calculator. With similar inputs as before, we're now able to calculate the thrust block volume required, as well as determine the height and width required for the thrust block.
Toolkit is Here
Well it's here! The MeyerFire Toolkit is past a beta version and ready for you.
To celebrate here's the latest version I've created and free access that runs through the end of September. You can download the complete Toolkit with installation instructions below:
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"Do not wait to strike till the iron is hot; but make it hot by striking." - William Butler Yeats
This site is built to start a discussion.
You see, I'm not a 30-year industry veteran, standard committee member, or organization technical expert. I'm perhaps a mediocre engineer, average illustrator, novice website developer and author. Perhaps the thing I'm best at is Microsoft Excel, but as the son of two accountants - that's just in my blood.
The only real unique angle I have is a combination of those items that I've used to compile these online resources.
In the end, though, that might be all it takes to start the discussion.
What is Wrong
I've seen fire protection that could be better and you probably have too.
I've seen design documents where fire protection is completely not-addressed, where even a "provide sprinkler heads throughout" would have been an improvement. There's bad installations, a lack of resources to review drawings & calculations, and educational resources that exist but aren't great.
Who We Are
Fire protection is a niche market.
You don’t need me to tell you that – far and away the majority of designers and engineers in the industry are comprised of small design outposts. It’s not the Jensen Hughes of the worlds that make up most of the industry – it’s the mom and pop contractors, freelancers, MEP firms, insurers, building owner’s engineers, and small fire protection consultants that make up the majority of fire protection design, installation and review in the US and abroad.
How do I know? I interact with these people all the time. People that are far smarter and more experienced than myself. The resources I’ve just started to share are not new – they’re just shared publicly across corporate borders for perhaps the first time.
You may already know - in fire protection we're the lone-gunners.
Mechanical and electrical engineering are massive industries. For every newly licensed fire protection engineer, there are 14 newly licensed electrical engineers and 17 new mechanical engineers. And that’s despite the tremendous growth we’ve seen in fire protection engineering in the last couple decades.
We're already on a small island compared to those disciplines.
We do have something that those massive fields don’t – we have the fire (pun intended). Fire protection designers, engineers, installers, and reviewers in my experience are far more passionate about this field than the average mechanical, electrical, plumbing or structural engineer.
We’re a niche market and I'm told constantly a "rare breed" (I think that's a compliment...). Being niche in addition to understanding the importance of what we do is part of what makes so many people in fire protection so passionate about our careers. It's the niche market and that passion that makes the community aspect of what we do so important.
I had lunch with a new colleague I admire last week who had previously worked in other fields and he specifically mentioned that the community within fire protection is a major differentiation for our industry.
Importance of Independence
I’m not a product manufacturer, I’m not a tiered membership organization, and I’m not a design standard. Believe it or not unless you’re one of about three people following this blog I’m also not a competitor to you or your company.
Independence on the part of this website may be the most important perspective I can create to offer something meaningful for the industry.
Why? Because if there’s something that the industry could use, I want to create it. If there’s a better, faster, leaner way of helping people like us do fire protection better, then this website is built to be right at that intersection.
The tools here are not limited to representing one manufacturer's products.
The articles here are not so high-level that you can read three full-page spreads and have nothing to apply to your workflow. I don’t write with the hope of sounding sophisticated.
A Rising Tide Raises All Ships
I’ve been asked before about why I’d consider sharing tools and resources I’ve used, when it’s essentially "training the competition".
As mentioned earlier; I’m really not a competitor. But more importantly, how much better could the industry be if there are greater numbers of people who are passionate, sharp, and involved in fire protection?
If we’ve all witnessed a lack of concern for fire protection, how could offering up the small things we learn as we go not help us all out in the end?
I still come across architects who had yet to work with or weren't familiar hiring a fire protection design team. How much better could the industry be served if fire protection were considered early in project development the way mechanical, electrical, structural and plumbing design is?
How much better could fire protection be if bid documents contained water supply information, well-established design criteria with the building owner’s involvement, and basic coordination such that the sprinkler installer isn’t the bad guy when he installs a main?
How much better could building owners be served if sprinkler contractors didn’t have to take on so much risk with bidding empty documents?
How much better would it be for review authorities if someone else was looking out for code compliance, and they didn’t have to be the bad guy every time?
Our past culture of minimal fire protection involvement early in project development doesn’t have to be our future.
With a basic set of competent specifications, contractors can actually give building owners what they want while making profit even in competitive bid scenarios – all while review authorities can receive better documents and better results.
Getting there isn’t a matter of mandating FPE involvement, forcing continuing education or ramming more requirements on the industry. In my opinion doing better fire protection is getting knowledge and tools into the hands of people that can use it. The more tools and help we can create, the better we're all served in the long run.
The Future of MeyerFire
This website is here for the long run.
I have been so thrilled to meet and hear from such a variety of sharp and passionate people after developing this basic website. My hope is that this website is a conduit that helps bring people to the industry, help share knowledge and help share resources that little by little move us all forward and up.
It's all about the movement towards better fire protection.
The tools posted here are literally about 3% of the ideas others have shared and I have down in writing for future development. There's so much to create and share, and it's just getting started.
This summer (July 11th) will see the launch of the Toolkit, which is a printable, savable, downloadable software package incorporating all of the tools on this website. For Weekly Exam users, July will also have an on-demand practice exams, offering unlimited runs of questions you've faced but with different inputs & solutions to extend your prep ability.
Later this summer and into the fall I'll be working towards new design tools & resources to add online and to the toolkit, while also helping support the ongoing community in the MeyerFire Daily space.
Between following the Blog, the Daily Questions, beta testing the new software package that will debut two weeks from today, or using the PE Exam Tools, thank you for being a part of the movement towards better fire protection.
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Joseph Meyer, PE, is a Fire Protection Engineer in St. Louis, Missouri. See bio on About page.