On every project containing fire alarm design I come across the same question repeatedly - does this unit require a duct detector?
In short, there's two prevailing standards that determine whether duct detection is required. The first (and most common in the United States), is the International Mechanical Code (IMC). Section 606.2 identifies areas where smoke detection is required for the purpose of mechanical unit shutdown.
The other prevailing standard is NFPA 90A, the Standard for Installation of Air Conditioning and Ventilating Systems. I'll address those requirements in a later post.
Back to the question at hand - there's essentially six different scenarios a mechanical unit can fall into under the International Mechanical Code. These do not include the requirement for multi-level duct risers over 15,000 CFM, but rather whether an individual unit requires detection at the unit.
Here is a quick cheatsheet summary concerning those scenarios:
If you review or design fire alarm systems regularly, take a look and let me know what you think.
If you know someone who might also benefit from cheatsheets like this, send them a link or tell them to subscribe here.
Hope you find this helpful and have a great rest of your week!
It is a popular and well-established concept that water and electricity don’t mix.
Water is electrically conductive which creates a major hazard of electrocution where a continuous pool of water meets a live electrical feed.
Can We Omit Sprinklers in Electrical Rooms?
On a few occasions I have come across building authorities and building owners who assume that sprinklers will not be installed inside traditional electrical rooms.
Why? The basic tenant that water and electricity don’t mix.
While the concept is important, the intent of sprinkler protection throughout a building is not just for each item within a building, but the building itself.
The primary intent of sprinklers is suppression – or stated differently – to prevent the growth of fire from the room of origin throughout a building. This includes all the rooms and spaces beyond just the electrical room where a fire could begin.
This week I’m digging into guidance surrounding electrical rooms.
NFPA 13 Guidance
NFPA 13 (2002 Section 126.96.36.199, 2007-10 188.8.131.52, 2013 184.108.40.206, 2016 220.127.116.11, 2019 9.2.6) allows sprinklers to be omitted in electrical rooms, but only where each of the following are met:
Concerns with Providing Sprinklers in Electrical Rooms
Providing sprinklers within electrical rooms could:
Prior to the 1994 edition of NFPA 13, important electrical equipment were required to have hoods (or shields) comprised of non-combustible construction to prevent direct contact by sprinkler discharge. All electrical rooms were required to be sprinkler protected.
Beginning with the 1994 edition, NFPA 13 introduced language to address concerns for firefighter safety and equipment damage. Sprinklers could be omitted in electrical rooms where the room contains dry-type equipment (no oils), is dedicated to electrical equipment only, is fire-resistant to reduce fire spread, and the room has no storage hazard.
The 2016 Edition, the requirement for equipment hoods or shields was removed to direct it under the scope of NFPA 70.
Just recently for the 2019 Edition new text was introduced such that no storage is permitted (non-combustible storage had been allowed) and liquid-type K-class (less flammable, non-spreading fluids) would be allowed.
International Building Code Input
The International Building Code (IBC) does not allow the omission of sprinklers “merely because it is damp, of fire-resistance-rated construction, or contains electrical equipment” (IBC 2000-18 18.104.22.168.1).
Within the same code section, the IBC does allow sprinklers to be omitted in “generator and transformer rooms separated from the remainder of the building by walls and floor/ceiling or roof/ceiling assemblies having a fire-resistance rating of not less than 2 hours.” These rooms must have an approved automatic fire detection system.
According to IBC commentary, buildings with sprinklers omitted in one of the sections allowed by the IBC would still be considered fully-sprinklered throughout and in compliance with the code and NFPA 13. This distinction is important as it carries eligibility for code alternatives, exceptions and reductions.
Combined, both the IBC and NFPA 13 require electrical rooms to be protected unless the prescriptive alternative option is followed.
As NFPA 13 commentary outlines, sprinkler systems have been successfully installed in rooms containing electrical equipment for over 100 years with no documented instances of a problem. While still seemingly controversial, most projects designed today include sprinkler-protected electrical rooms.
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When I was six years old, I came home from school unexpectedly excited one day.
I ran up our driveway, pushed wide the door and yelled to my mom.
“You won’t believe it! There’s this place at school where you can go through shelves and shelves of books and pick out anyone you want –
and it’s free! They call it a library.”
It wasn’t one of my mom’s proudest parenting moments, but in our house, we never pretended to be great readers… or apparently even pretended to introduce kids to a library.
I guess I’ll just come out and say it… Both of my parents are accountants.
Now, I know what you’re thinking, and yes, the accountants are where my well-rounded sense of humor comes from.
But there’s another big benefit to having parents as accountants –
and it’s having a love for spreadsheets.
I’m not sure if little excel formulas naturally run through my veins or whether it was every family calendar my parents ever created, but one way or another I thoroughly appreciate the power a spreadsheet has.
Even if your parents are not both CPAs, there’s a place for Microsoft Excel in your engineering life.
Excel isn't just made for your uncle accountant anymore - there's potential any engineer can love.
For one, Microsoft Excel is not called
the “Swiss Army Knife of Software” for naught. Excel is a blank canvas for any calculation you need to make. You can quickly create and repeat repetitive calculations to speed up and organize your workflow. You can complete reports, forms, create charts, tables, organize content, or use any of a myriad of highly powerful tools.
Here are a few of my most often used formulas:
That’s pretty much all of my secret sauce. About 95% of the tools created combine those formulas alongside mathematical operators (like max(), min(), sin(), sqrt(), etc.).
One of the best parts about using Excel is that you may already have access to it. If your company has a Microsoft Office suite (or what’s now their subscription model with Office 365), you already have access to these tools.
Creating helpful resources is what we’re all about, and Excel is the epitome of giving you, the rockstar designer or engineer, the ability to create and flourish with the tools you need.
You didn’t get into the industry to do poor, sloppy work. You came here to help save lives. We shouldn’t have to wait for programmers to create the daily tools we need to do great work. Excel is one way you can organize and validate the great work you do.
There came a point near the end of my undergraduate work and at the beginning of graduate school where I realized I needed to create a clean, organized method to show details within calculations. The method I slowly developed needed a single logic path, had to be easy to follow, would thoroughly explain the process, and had to allow the easy repetition of the work.
What’s resulted is the standard format that’s used in the PE Prep Guide and on many of the tools you’ll see around this site. Concepts are researched, painstakingly created, tested, refined, tested, refined, beta tested, and refined more.
Standard formatting for MeyerFire tools - note the equations and worked examples with references cited.
If you’ve followed the blog for a while, you already know the blog, daily forum, and even the PE prep materials are all created to help foster discussion that leads to shared expertise and knowledge.
Outside of a few major players and organizations, the fire protection industry is comprised of thousands of thousands of small outfits that welcome this shared expertise. Our industry thrives on the contributions from a wide spread of individual parties.
Don’t let me or anyone else douse your enthusiasm to create resources that improve your ability to impact the industry.
Keep on keepin’ on.
Oh and remember to take your kids to the library.
I've heard from a handful of people to be sure to explore topics other than just fire suppression. I agree! There will be plenty more to come.
It only seems appropriate after discussing the fire suppression cheatsheet and the code call cheatsheet in the last few weeks to also compile the latest cheatsheet I have for fire alarm design.
Here's a blank cheatsheet and an example:
If you're already using the Toolkit this is now available for download with today's update. Just log in here to get it.
Along with having all of your design decisions documented for a project (or flagging the open items still left to figure out), perhaps the most important piece is how quickly you're now able to record your notes.
If you don't see the video recording below, click here for a YouTube video of how quick notes can be recorded.
MeyerFire was created to help you shine in fire protection. Know someone who might be interested in these tools or articles? Email a friend with a link today. Thanks for being a part of the effort towards better fire protection!
Unless you're tuned in as an AHJ yourself, you've likely made a few "code calls" to a code authority and asked a litany of questions to make sure your project's design meets the local requirements.
I'm not even sure if the term "code call" is a common term, but I've heard it enough that I suspect you already know what I'm talking about regardless of where you call home.
I enjoy this process now, but I didn't always. Fresh out of school I'm pretty sure I was visibly shaking the time I first made a code call. I was sure that within seconds my cover would be blown and it would be all too obvious that I had no idea what I was talking about. Despite my awkwardness (I make a good engineer, right??) nothing went sour and since then I've slowly learned and repeated many many times.
There was even one of my favorite code calls that I made about an elementary school to coordinate local fire alarm requirements. It was only right after the call late on a Friday afternoon that I found out that the fire marshal I just spoke with was hired onto our team and was starting the following Monday. They say fire protection is a small world, right? He turned out to be one of the most knowledgeable people I know and one of my favorite people to work alongside.
The Joys & Pains of Code Calls
Code calls also come in many different flavors.
Sometimes I'm just shocked by how friendly and helpful code authorities are. I once made a call at 15 minutes till 5pm on a Friday to a small town in Arkansas, thinking I would just leave a voicemail. After my questions, I asked if the department conducted flow tests, and while he said they did, he apologized that because of a prior commitment he couldn't do it then but would be happy to do it first thing Monday morning. I almost fell out of my chair. Very helpful and caring people in this field.
On the contrary, sometimes the hardest part about a code call is just finding the right person to speak with who is actually responsible for plan review of fire protection systems and getting a few minutes of their time. Not to pick on New York City because I love the people there and speak with a handful of you regularly, but if you're trying to get a hold of someone to verify or coordinate a few particulars of your system... well... good luck! Maybe it's because they knew I can't stand the Yankees.
I also sometimes get AHJs who simply say all they do is 'per code' and they aren't interested in talking specifics. The whole point of the call is filling in the gaps where a code or standard does not direct but rather defers decisions to the AHJ.
Want a siamese fire department connection with national thread, or a Storz-type? Either way is code compliant. As an engineer I can make either way work.
Is a wall-mounted FDC permissible, or does it need to be freestanding? Either location is compliant, but NFPA 13 says the location needs to be coordinated with the AHJ.
What I've gathered and refined over hundreds of code calls is my cheatsheet I currently use today. Just like the design cheatsheet, if you're using the Toolkit you can quickly highlight categories for your record keeping.
What's even better about this tool, though, is that you can quickly fill in the content (while on the call) and then right after save as a PDF and email to the AHJ themselves. Want them to have a record of the call and a quick way to verify your notes? Great! You now have a logged code call and the AHJ has an opportunity to review your notes.
The process of calling, taking notes, and composing the email used to take close to an hour total. This tool alone brings that total time to about 15-20 minutes. That's three-quarters of an hour you could save on every job you make the call!
A Radical Big-Picture Concept
One of my longer big-picture ideas to help the industry is to beta test and, if successful, open up a larger code-call database. I envision this as a database that brings designers and code authorities together to make local requirements clear and help jurisdictions get installations that reflect their preferences and mandates.
Want to know what hydraulic safety factor is required for sprinkler systems in Springfield, Illinois? Great - a quick query in the database reveals that and a clean list of other local requirements.
Want to know what type and location for FDC's that Tucson, Arizona requires? Great, we'd have that too.
This would clearly have a huge value for designers and engineers - but what I'm really curious about is how to incentivize code authorities to take the survey or help us populate the database. If you're an AHJ, email me (firstname.lastname@example.org) or comment below about whether you'd be open to the idea of making your local requirements public in a database.
I would have to think that AHJ input would only help local authorities get installations that match their needs - but I also know that getting action out of anyone is only possible with mutual benefit and sometimes incentives.
Just like the Design Cheatsheet posted a couple weeks ago, this form is integrated into the updated version of the MeyerFire Toolkit ready for download today. Below is a blank and filled-in template.
If you're already a Toolkit user, you can download the code call cheatsheet today by logging in here. If you're not using the Toolkit, you might consider joining in on what's quickly becoming what some consider the best tool for fire sprinkler design under $200. See more about it here.
The Questions on My List
The current code call checklist I use today has had items added and scratched over years of finding out what's important and what questions always get the same answers.
That being said, there's no real one defined list that matches everyone's preferences. What questions do you ask that you feel are important to the design that's not explicit in code? Comment below.
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I had several long standing global concerns when I was in grade school.
It wasn't general anxiety or depression-related, but I certainly felt as though the weight of worldwide issues hung squarely on my small shoulders.
At the time in school there was a major focus on the environment (I would imagine there likely still is now). It wasn't just a hard-sell on earth day, it was the disappearance of rain forests, erosion due to overbuilding, overpopulation, oil spills, our reluctance to recycle, and the overzealous use of oil that would undoubtedly cause our planet irrevocable damage. It was our generation's tasks to make right what generations before had begun.
The gravity of the concern didn't feel just environmental either.
New media opened the front door to war, disease, and a myriad of reasons to be pessimistic about the future and the world our kids will someday inherit.
Now years later, as a father, I've heard similar sentiments prevail; "how could someone bring a child into the world today?" "I can't imagine how to parent with all the (fill in the blank) going on today." "Will there even be X around when our kids are old?"
I'm not going to pretend that everything is sunshine and roses for everyone. There are major geopolitical issues and wars and famine and poverty and disease. A great day for me could also be the worst day for someone else.
What I am hear to say is that when you adjust your focus from the immediate present and look out a just little more distant - there is so much promise in the world. And by so much promise I mean that the planet is getting healthier, cleaner, and the quality of human life is improving in ways that we've never seen before in human history.
There has actually never been a better time to bring a child into the world.
In Peter Diamandis and Steven Kotler's 2012 bestseller "Abundance: The Future is Better Than You Think", an author and engineer review historical data and trends that show how technology is achieving exponential improvements in computing, energy, and medicine.
This bestselling book details many eye-opening reasons for optimism with the trends our societies are experiencing.
These independent technology-based innovations have and will continue to drive major improvements to clean water access, food, energy, health care, education, and other facets of a first world standard of living for the planet's future nine billion people.
Not only does mainstream media not cover the positive trends in the world today, but the future of our planet is looking more urbanized, education, cleaner, and healthier.
Speaking of population, the United Nations recently released a DESA report projecting nearly 10 billion people in 2050 and over 11.2 billion people in 2100. Since this latest update there's been fairly widespread disagreement about these figures, with many researchers speaking out out about the projections that hinge on one major flaw: population growth rates are declining. Some countries have already peaked in population and are now in decline without immigration. Many expect that we, as a planet, will never reach more than 10 billion people.
This isn't news to you if you live in Europe or Japan, of course, but in the U.S. many of us seem unaware of this major global trend. Research shows that with urbanization and better education, couples have less children. This speaks to major positive impacts in using less resources and shaping a cleaner planet in the future.
Trends in Fire Protection
That's great Joe, but what does this have to do with fire protection?
First, as is my underlying theme in the whole website - engineering is going to save the world. I'm sure my wife would also suggest that scientists deserve some credit too, but this isn't her blog.
Second, don't be discouraged if you feel that the quality of our line of work is in freefall, that no one is entering the industry, or that we've lost all sense of pride in what we do. Big-picture trends in fire protection are very positive, with death rates due to fire steadily decreasing per capita over the last century. The unrelenting overall trend is that we are doing something right as fewer people per capita are dying now from building fires.
Fire fatalities have been and continue to decrease with advancements in code adherence, our knowledge of fire protection, and shared education of the subject. Just the last 30 years across Europe and the US there's been major improvements in fire safety:
Global trends in fire deaths have decreased over the last quarter-century as shown in this US FEMA study.
Third, if you've ever felt similarly barraged by the negativity in the media or fears that we're only one step away from global catastrophe, I would wholeheartedly encourage you to read or listen to the book Abundance: The Future is Better Than You Think.
There's no summary that I could put together that I feel would do the book justice.
Of the fifty-plus books I read last year this was without-a-doubt the most impactful. [On a side note, if you're wondering how I average 50 books a year - I cheat and listen on audible.com. You can actually get the book Abundance and another book, for free, with a free trial here]
If you've read Abundance, comment below on your impression. If not, I'd highly encourage you to read it and let me know what you think (shoot me an email at email@example.com). I promise the read will be worth your time.
If you've enjoyed this article, consider subscribing to these free weekly posts here.
Here's a few other book reviews:
Chicago Death Trap: The Iroquois Theatre Fire of 1903
Fahrenheit 451 & The Thirst For Knowledge
Triangle: The FIre That Changed America
Diamandis, Peter H. Abundance: the Future Is Better than You Think. Simon & Schuster, 2015.
Fire Death Rate Trends: An International Perspective. FEMA, July 2011, www.usfa.fema.gov/downloads/pdf/statistics/v12i8.pdf.
United Nations Population Division | Department of Economic and Social Affairs. United Nations, www.un.org/en/development/desa/population/publications/trends/population-prospects.asp.
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Here's the top ten most popular articles and posts in this past year:
I hope you've had a great 2018 and are looking as forward to the coming year as I am.
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We are excited to bring in the new year with some big plans for 2018. This week we're quickly recapping the most-read articles over the past 12 months:
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While smoke detectors often have recommended spacing of 30 feet (identified in manufacturer's product data), spacing 30-feet on center is not the only way to space smoke detectors. NFPA 72 offers two methods for spacing smoke detectors on smooth ceilings:
The first method is simply to provide detectors at their listed spacing (often 30 feet), center-to-center, and within half the distance (which is 15 feet) to walls. [NFPA 72 2002 22.214.171.124.3(A-B), 2007 126.96.36.199.3.1-.2, or 2010-2016 188.8.131.52.1(1)]
The second, often lesser-known method, is to provide smoke detectors such that all points on the ceiling are within a distance of 0.7 times the listed spacing, or less [NFPA 72 2002 Section 184.108.40.206.3(E), 2007 220.127.116.11.3.5, or 2010-2016 18.104.22.168.1(2)].
Applying the Method
In practice, this simply results in drawing a 21 foot circle (0.7 x 30-foot spacing = 21 feet) around each detector and making sure that every point on the ceiling is covered. On site, it would simply result in making sure every spot on the ceiling is within 21 feet of a smoke detector.
This second method becomes important for complex room configurations, long and narrow corridors, or as a way to simply provide smoke detectors at their most efficient coverage.
A corridor which is 100-feet long and 10-feet wide, for instance, would require 4 smoke detectors under their listed spacing (30-feet spacing on center and 15-feet to the corridor ends). Using the second spacing method allowed by NFPA 72, these smoke detectors can be spaced nearly 41 feet center-to-center, requiring only 3 smoke detectors to be used.
Using the Second Method
Fundamentally, the theory is that smoke production will fill a ceiling based on the area of the ceiling. For a long, narrow corridor, smoke will be limited in it's spread in the narrow dimension, forcing travel down the corridor. As a result, smoke detector response time is dependent upon the amount of area the detector covers, not necessarily the spacing between detectors.
Matching smoke detector layouts to the nature of smoke transport and this code allowance could result in a simpler approach and often the need for less smoke detectors overall.
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Joseph Meyer, PE, is a Fire Protection Engineer in St. Louis, Missouri. See bio on About page.