This week, we're featuring a segment that comes from our MeyerFire University platform. This one is just one of 900+ that make up MeyerFire University.

It answers a fundamental question that many life safety consultants and electrical and fire protection engineers encounter at some point: where do we need exit signs?

Unlike sprinkler or strobe locations, placing exit signs leans more towards the 'performance' end of the spectrum rather than purely 'prescriptive,' where there's a little more art to the process than straight numbers.

For this one, Fire Protection Engineer Steven Barrett takes the reins and explains a walkthrough example.

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If these types of segments would be helpful for you or your team, join us at www.meyerfireuniversity.com (it's more affordable than you think), and be sure to subscribe to our YouTube channel as well.​

Thanks and have a great rest of your week!

​- Joe

By Jocelyn Sarrantonio, PE | Fire Protection Engineer / Technical Director at MeyerFire

Although the 2024 editions of the International Building and Fire Codes have been out for some time, new codes don’t get used until a jurisdiction adopts them.

Now that I’m starting to see them referenced more often in project work, it feels like the right time to dig into what’s new. The humor is not lost on me that, as we begin to wrap up 2025, I’m finally getting deep into the changes to the 2024 codes.​

Before we get started, if you haven’t taken the MeyerFire University LS111 course [here], it’s a great series on Effective Use of Codes & Standards. One of the many helpful items that Fire Protection Engineer Sean Donohue reviews is how to tell code language has changed.

Not to be all “back in my day”, but when we only had the print and PDF editions of codes, we were used to seeing the vertical bar near new sections of code.

Now, since most of us use the online versions, we should realize that new text is indicated in blue text, deletion arrows (→) are used for deleted text, and stars (*) for relocated text.

The intent here is not to cover every single change here, but to highlight some of the provisions that may impact the day-to-day workings of someone in the fire protection engineering profession. As always, and I really cannot emphasize this enough, check your local amendments. Very few jurisdictions will adopt the codes outright; they’ll often make some changes.

OCCUPANCY CLASSIFICATIONS (CHAPTER 3)
While the official classification of occupancies is typically up to the architect, it’s important to know what to expect with these changes. It will come as no surprise that changes have been made to certain occupancy classifications due to their use of lithium-ion batteries in energy storage systems (ESS). Examples include:

• Group B: Lithium-ion or lithium metal battery testing, research, and development
• Group F-1 (moderate hazard factory, industrial): ESS and equipment containing lithium-ion or lithium metal batteries, or occupancies with lithium-ion batteries or vehicles powered by lithium-ion or lithium metal batteries, are classified as F-1.
• Group S-1: Storage of lithium-ion or lithium metals, or vehicle repair garages for vehicles using lithium-ion or lithium-metal batteries, would be classified as S-1

What’s the impact here?

To start, the F-1/S-1 designation is for moderate-hazard, and the F-2/S-2 classifications are for low-hazard occupancies. These classifications are helpful, as the occupancy classification of areas using ESS could fall into a bit of a no man’s land. ESS regulated by IFC Section 1207 would be exempt from regular Group H requirements, so prior to this change in IBC 2024, there wasn’t much direction on what to classify these occupancies as. Since “electrical rooms” aren’t listed in Chapter 3, generally I would see large UPS or Electrical Rooms be classified as either Group B, F-2, or S-2, maybe matching the predominant occupancy of the building.

However, classifying these spaces as the more hazardous designation of Group F & S has a trickle-down effect for the rest of the fire protection features. There are differences in allowable areas, separations for mixed-use occupancies, and means of egress requirements between Group F-1/S-1 and Group F-2/S-2. For example, in a sprinklered F-1/S-1 occupancy, travel distance is limited to 250 ft, as opposed to 400 ft for F-2/S-2 occupancies.
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Another important implication would be for smoke and heat removal. Section 910.2.1 requires smoke and heat vents, or a mechanical smoke removal system for Group F-1/S-1 occupancies with more than 50,000 square feet of undivided area. That may seem like quite a large area, but data centers can easily exceed this limit. And I’m sure you could guess that if I have a giant room full of servers and specialized equipment, the last thing I want is multiple roof penetrations overhead. 

As we’ve covered in our two ESS courses, these additional safety features are well warranted due to the risks presented by lithium-ion batteries. And to be fair, the ventilation system I am probably providing for my ventilation and explosion control probably counts as a “mechanical smoke removal system”. But the point here is that it’s important to think of the ripple effects of seemingly small and straightforward changes. The change is contained in Chapter 3 for Occupancy Classifications, but it trickles down to items in Chapters 5, 6, 9, and 10.

CHAPTER 9, SECTION 903 CHANGES
The next place where we’ll see some big changes is in Section 903. We do have an IBC Cheatsheet that lists when sprinklers are required per Chapter 9, which you can find below. 

The cheatsheet includes footnotes for new provisions in 2024, but it should come as no surprise that many of the provisions are for occupancies that use lithium-ion and lithium metal batteries. These include:

• Group B: Throughout fire areas of laboratories involving research, development, or testing of lithium-ion of lithium metal batteries.
• Group F-1: Throughout the building for occupancies that manufacture lithium-ion and lithium-metal batteries, or manufacture vehicles, and ESS containing lithium-ion and lithium metal batteries.
• Group M: In the room or space within a Group M occupancy where required for the storage of lithium-ion or lithium metal batteries, per IFC Section 320 or Chapter 32.
• Group S-1: Throughout the building where fire areas used for repair garages or the storage of lithium-ion or lithium metal powered vehicles exceeds 500 square feet.

An additional change is the design parameters for the sprinkler system, when it is required, to protect these areas containing lithium-ion or lithium metal batteries:
“… design of the system shall be based on a series of fire tests. Such tests shall be conducted or witnessed and reported by an approved testing laboratory involving test scenarios that address that range of variable associated with the intended arrangement of the hazards to be protected.” -IBC 903.3.1.1.3

That’s pretty explicit language here, which is extracted from the fire code. There is no one-size-fits-all solution, and the system design should be based on fire testing. But because we’re fire protection folks we know that we probably aren’t going to have all of that information at the time we need it. It would be great if we had fire testing data for all of the items that would be stored in a given facility, but we know that’s not realistic. In this case I would defer to the Fire Code, which in Section 1207 lists a sprinkler system density consistent with Extra Hazard Group 1 for certain situations. If I don’t yet have testing information, that’s a safe density to use so I can start planning my water supply and sizing my pump.  
 
OTHER CHANGES OF NOTE
Even though pixels are basically free, this post would become unreadably long if we went in depth for each change! To summarize the rest of the IBC 2024 changes of interest:

• Incidental Use Table 509.1: There were a few entries in Ambulatory and Group I occupancies that previously required a 1-hour separation only, and have been updated to require a 1-hour separation and an automatic sprinkler system.
• A new table is included (Table 307.1.1), which outlines specifically what sort of materials are exempt from Group H occupancy classifications, although still regulated by the Fire Code.

• Chapter 9 has a revision for the use of NFPA 13R systems. Previously, the permission to use NFPA 13R applied to all Group R occupancies. Among other restrictions, it limited the highest floor of the Group R occupancy to 30 feet above the lowest level of fire department vehicle access. Now in 2024, for Group R-2 occupancies only, the measurement is to the roof assembly, and is limited to 45 feet.  If you don’t do a lot of residential work, Group R-2 is generally multi-family residential buildings like apartments, condos, and dorms.
• A change was made to the waterflow alarming in Section 903.4.3. Previously the waterflow device requirement was audible only, and now this alarm is required to be audible and visible.
• Section 904 for Alternative Extinguishing Systems now has a reference to NFPA 770 for hybrid fire extinguishing systems.
• Section 905.4 for Standpipe Systems has been revised to explicitly include exterior exit stairways, rather than just interior, in the hose connection location requirements.
• Changes to manual fire alarm system thresholds for Group A-5 outdoor bleacher-type seating, providing relief in certain situations where a public address system is provided, among other requirements.

And similar to the sprinkler changes for areas with lithium-ion and lithium-metal batteries, a fire alarm system required, activated by air-sampling or radiant-energy sensing detection systems, for the following areas:

• Group B: Throughout fire areas of laboratories involving research, development, or testing of lithium-ion of lithium metal batteries.
• Group F-1: Throughout the fire area for occupancies that manufacture lithium-ion and lithium-metal batteries, or manufacture vehicles, and ESS containing lithium-ion and lithium metal batteries.
• Group M: In the room or space within a Group M occupancy where required for the storage of lithium-ion or lithium metal batteries, per IFC Section 320 or Chapter 32.
• Group S-1: Throughout the fire area where required for the storage of lithium-ion or lithium metal batteries per Section 320 of the IFC.

Once we get into Chapter 10 for Means of Egress, one notable change includes:

• New exception for eliminating low-level exit signs in NFPA 13 or NFPA 13R sprinklered Group R-1 occupancies. Again, for those of us who don’t do lots of Group R work, that’s transient lodging like hotels, motels, and resorts. 

Like every new iteration, this code cycle brings a mix of fine-tuning and forward-thinking. Many of the 2024 reflect something that’s not new: the emerging risks of energy storage systems using lithium-ion batteries. But there are plenty of smaller tweaks, including the visible sprinkler system alarms and standpipe hose connections in exterior stairs, which will find their way onto our next set of plans too. Even seemingly small changes, or those that we think are “out of our scope” may have big downstream effects that impact all of our design and construction partners.

What other changes to the 2024 IBC and IFC have impacted your projects? Comment to share your stories below.

Thanks for reading, and remember to keep learning, because the code never stops changing!

​- Jocelyn