The newest edition of NFPA 13 will be adopted as early as 2022. However, the vast majority of states and jurisdictions will be adopting the new standard in January of 2023 with California being one of these states. In this article we will be focusing on the latest changes to the storage chapters and as they compare to the 2019 Edition of this standard.

The 2022 Edition of NFPA 13 carries forward the reformatting changes of the 2019 edition. In this new edition the intent was to further simplify each of the storage chapters and to add new fire protection information based on continued research and testing.

For brevity we will be reviewing these updates to the standard in a bulleted list:

General

• NFPA 13 2022 formatting is based on NFPA 13 2019 formatting, but with many editorial and technical changes throughout
• Sections in NFPA 13 2022 were in many places reformatted, merged, split, reworded, or deleted – making keyword searches difficult when transitioning from prior editions
• An electronic PDF version of the standard is no longer available. Instead, a web version was created, and which is accessible behind a paywall (subscription based). A free version is also available (with reduced functionality)
• A commodity classification ranking is defined in Section 20.3.1.3, which ranks commodity classes by severity. This allows a protection scheme designed for a higher class (ranked) commodity to protect a lower class commodity
• Protection schemes previously listed under ‘Miscellaneous Storage’ are now divided into two categories, (1) protection schemes for ‘Low-Piled Storage’ of Class I-IV up to 12 ft and plastics up to 5 ft, and (2) protection schemes for storage meeting the definition for ‘Miscellaneous Storage’ and storage heights up to 12 ft
• Supervision requirements for dry pipe systems were added in Chapter 8 i.e., automatic supervision of fire protection systems for more than 20 sprinklers on the same system
• New CMDA categories defined as “New System Criteria” and “Evaluation/Modification of Existing Systems”:
  • “New System Criteria” now tabulates values taken from the CMDA density curves, but limits them to values for 2000 sf sprinkler operating areas only (however, previous Single Design Points were included in these tables)
  • “Evaluation/Modification of Existing Systems” sections, figures and tables still show well-known density curves found in the 2016 and 2019 editions of NFPA 13. These (previous) density curves shown in figures are more flexible than the “New Systems” tables and can be used to calculate densities other than densities limited to 2000-sf sprinkler operating areas
  • Additional changes to the CMDA chapter are discussed below under ‘CMDA Protections’
• Several new sprinkler protection options were added for Class I-IV and Group A Plastics including new ‘Alternative Protection’ Options in Chapter 25 (In-rack Chapter).
• Chapter 25 (in-rack protections) was rewritten. Many new density tables and design criteria in tables were added. (Previous) density curves for “Evaluation/Modification of Existing Systems” in newly designed figures were added at the end of the chapter. Figures for in-rack arrangements were updated and associated captions were clarified
• Ceiling slopes for storage applications are still limited to 2 in 12, unless in-racks are installed that are independent from the ceiling sprinkler system (Section 25.6), in which case ceiling slopes can be exceeded and if no storage is placed above the topmost in-rack level. See also exception 20.9.1
• Special Design protection schemes (2016 Edition: Sections 16.2.4.1.2 & 17.2.4.1.2) were relocated into Chapter 26 under Section 26.4.1.2 (CMDA) and 26.4.1.3 (ESFR)
• Solid Shelf: Solid Shelf requirements are separated into several chapters (Chapters 3, 4, 20-25)
  • Miscellaneous Storage has no solid shelf protection requirements for Class I-IV and storage heights up to 12 ft and plastics up to 5 ft. Plastics and storage heights above 5 ft may require solid shelf protection. Low-piled storage does have a solid shelf protection requirement
  • Solid Shelf conditions were relocated to Chapter 20 in Section 20.19
  • Missing in-rack design exceptions as discussed in 2016 Edition i.e., if solid shelf conditions are met and face sprinklers are installed with min. 60 gpm, the in-rack water demand does not have to be balanced with ceiling sprinkler system (2016 Edition: Section 17.1.5.7)
  • Double Row Racks with open shelves are now considered ‘solid shelf’ where longitudinal flue spaces are not met – unless these types of racks will meet the exception listed in Section 20.5.3.1.2.2
  • Multi Row Racks with open shelves are considered ‘solid shelf’ regardless – unless these types of racks will meet two exceptions listed in Section 20.5.3.1.3
• Special Occupancy Requirements chapter 26 was moved to chapter 27. Chapter 27 is a complete rewrite and no longer contains detailed protection requirements for specific occupancies, but rather pointers to the associated NFPA standards for further reference and details

CMDA Protections

• Errata: Table 21.5.1.1 (Single-, Double-, Multiple Row Rack Protection for Cartoned Group A Plastics), 25-ft storage under 30-ft ceiling height is permitted without using in-rack sprinklers, if clearances from top of storage to ceiling is less than 10 ft. In this case a sprinkler density of 0.8 gpm/ft² is required [i.e., the dividing horizontal line in the storage column of this table has to be moved up by one row, see errata 13-22-2]
• Errata: Class I-IV tables in Chapter 25 (Tables 25.3.2.1.2.1 (A) and 25.3.2.2.2.1 (A) ) and associated paragraphs are titled (1) exposed-unencapsulated or (2) exposed-encapsulated or cartoned-unencapsulated and cartoned-encapsulated. In previous editions of NFPA 13 no sub-classification for protection schemes among cartoned and uncartoned commodities were made for Class I-IV (other than Class I-IV encapsulated vs. Class I-IV unencapsulated) and this continues to be correct for the 2022 Edition. Therefore, these new sub-classifications need to be ignored as they were added in error
• Errata: Figure 21.4.1.7.1 Densities without in-rack sprinklers and storage heights above 20 ft for “New Systems Criteria” are higher when compared to densities based on “Evaluation/Modification of Existing Systems” [fixed with errata 13-22-3, reverting to 2019 Ed. Figure 21.4.1.7.1 instead]. Note Figure 25.8.2.2.2.2(A) (CMDA ceiling density adjustment using in-rack sprinklers) is unaffected by this change
• No density adjustments based on rack aisle width for “New Systems Criteria” (with in-racks or without in-racks). However, density adjustments based on rack aisle width still exist for ceiling densities based on the “Evaluation/Modification of Existing Systems” method (previous density curves)
• No density adjustments without in-rack sprinklers for storage heights above 20 ft for “Evaluation/ Modification for Existing Systems”. Figure 21.4.1.7.1 (shows a truncated curve above 20 ft, or 100%). However, the web version of NFPA 13 shows the expected exponential increase of density with storage height above 20 ft. It should be noted that the tabulated values for “New Systems Criteria” densities and storage heights above 20 ft incorporate the expected exponential increase.
• Class I-IV: “New Systems Criteria” and “Evaluation/Modification for Existing Systems ” densities available for storage heights ≤ 25 ft
• Class I-IV: “New Systems Criteria” tabulated densities for storage heights > 25 ft. But there are no “Evaluation/Modification for Existing Systems” densities available for storage heights > 25 ft
• Plastics: “New Systems Criteria” tabulated densities for all storage heights. But there are no “Evaluation/Modification for Existing Systems” densities available for any plastics and all storage heights
• Plastics: Cartoned sprinkler options reduced for storage heights ≤ 25 ft
• In-Rack water demand in Table 25.3.1.1 is overwritten by in-rack water demand listed under Notes in Figures 25.3.3.X.1.1, etc.
• Solid Shelf: No protection options discussed for storage heights > 25 ft
• Solid Shelf: In-rack water demand discussed in Table 25.3.1.1

ESFR Protections

• Ceiling densities only dependent on ceiling heights for Class I-IV and all Plastics
• Plastics: Cartoned-expanded: no 32-ft options available anymore. Exposed-unexpanded: no 35-ft options available anymore (K-16.8 ESFR for storage heights > 30 ft were removed and require now high water demand options such as K-25.2 ESFR at 60 psi)
• Errata: Footnote ‘b’ in Table 23.3.1, should reference Section 23.4 (not 27.4)
• Obstructed combustible ceiling roof construction is now permitted for ESFR systems
• ESFR systems are permitted to protect Extra Hazard occupancies for any storage arrangement (not just Miscellaneous Storage)
• Light and ordinary hazard occupancy protections with ESFR systems only have to meet obstruction requirements for standard sprinkler protections (not ESFR)
• ESFR sprinklers are permitted below conveyors without high-piled storage underneath
• Solid Shelf: Requirements discussed in Section 25.5.1

CMSA Protections

• Class I-IV and plastics: Changes throughout the tables, new K-25.2 options added
• Solid Shelf: Requirements discussed in Section 25.4.1

Alternative Protection

• Now titled ‘in-rack sprinkler protection options independent of ceiling-level sprinklers’
• New protection options were added (Options 1, 2A, 2B, and 3) with Option 1 representing the original protection scheme of the 2016 Edition (previously known as ‘Alternative Protection’)
• Solid Shelf: Requirements discussed in Section 25.6.2.5.2

Conclusion

In continuing the new format introduced in the 2019 Edition, the new revision of this standard shows many improvements and additions. Overall usability has improved though not for all chapters. Then this new edition is a significant update to the 2019 Edition and in many ways is building and improving on its well-known heritage.

Eliminating the PDF version of the standard is regrettable, because the web version is simply nowhere near as useful. However a hard copy is still available and it is highly recommended.