A new edition of NFPA 13
By Samuel S. Dannaway, PE,
President, S.S. Dannaway Associates, Inc., Honolulu, Hawaii
The 2010 edition of NFPA 13, Standard for Installation of Sprinkler Systems, is now available. It was issued by NFPA’s Standard Council with an effective date of 26 August 2009. The 2010 edition of NFPA 13 is the 59th edition of the standard, which was first published 1896.
NFPA codes and standards typically identify changes and additions to text, tables and figures from the previous edition with a bold line to the left of the item and, in the case of information that was removed, with a black bullet. The 2007 edition of NFPA 13 had a total of 392 pages, while the 2010 edition has 424 pages. The following are some of the significant changes:
Paragraph 7.1.2.1. All wet pipe sprinkler systems are required to be provided with a minimum 1/2-inch relief valve to relieve any pressures exceeding maximum system working pressure. Previously this requirement only applied to gridded sprinkler systems.
Paragraph 8.5.4.1.4. The use of heat collectors (e.g. pie pans) to assist activation of sprinklers, in lieu of locating the sprinkler properly with respect to the ceiling, will no longer be permitted.
The obstruction rules for spray and residential sprinklers now include a paragraph about ceiling fans. If fans blades are less than 60 inches and the plan view of the fan is at least 50% open sprinklers can be spaced without regard to the blades. An annex note clarifies that the motor, housing is still subject to the “Three Times Rule”. For residential sprinklers there is no 60 inch limit.
Paragraph 8.15.5.6. Sprinklers must be provided at the top and bottom of elevator shafts that use polyurethane-coated steel belts or other similar combustible belt material.
Paragraphs 9.2.1.3.3.4 and A.9.2.1.3.3.4. Where flexible sprinkler hose fittings are used in a suspended ceiling a warning label about relocating the sprinkler must be provided. The annex provides sample wording for the label.
With respect to bracing for earthquake protection new Zone of Influence tables were added for Schedule 5 steel pipe, CPVC pipe, and Type M copper tubing. Also, the method for calculating loads in the Zone of Influence was revised to be in conformance with Chapter 13 of SEI/ASCE-7 Minimum Design Loads for Buildings and Other Structures.
There are several significant changes in the storage chapters of NFPA 13.
Paragraph 12.1.1 Roof Vents and Draft Curtains. These provisions have been revised to make it clear that roof vents must be manually operated or automatically activated by an operating mechanism with temperature ratings higher than sprinklers. Also, ESFR sprinklers may not be used in buildings with automatic vents unless the vent operating mechanism uses a high temperature standard response rating. Draft curtains may not be used within ESFR system boundaries areas but can be used at boundaries separating ESFR systems from other types of systems. These provisions may conflict with jurisdictions enforcing the International Fire Code or NFPA 1 Fire Code so designers may need to resolve any conflicts with the AHJs.
12.1.3.4 Excessive Clearances. The rules have been expanded and clarified for cases where there are excessive clearances between the top of storage and the ceiling.
The term “large drop sprinkler” has been eliminated. Large drop sprinklers are now considered a form of Control Mode Specific Application (CMSA) sprinklers and all large drop requirements have been consolidated into provisions for CMSA sprinklers.
Figure 13.2.1 for Miscellaneous Storages and Figures 14.2.4.1 & 14.2.4.2. The density curves were modified to limit the maximum design area to 3,000 sq. ft. instead of 5,000 sq. ft., which was previously allowed. The change was made due to concern that too many sprinklers are allowed to operate with the larger design areas.
In Chapter 20 three new sections were added to address special storage criteria for storage of records and files:
20.5 Sprinkler Protection of Carton Records Storage with Catwalk Access. This section includes criteria for ceiling sprinkler protection and requirements/criteria for sprinkler protection below each catwalk level.
20.6 Compact Storage of Commodities Consisting of Paper Files, Magazines, Books, and Similar Documents in Folders and Miscellaneous Supplies with No More Than 5 Percent Plastics up to 8 ft. High.
20.7 Protection of High Bay Records Storage. This provides criteria for ceiling only sprinkler protection of fixed or mobile shelving units greater than 12 ft. and up to 34 ft. high.
In Chapter 21, the sprinkler requirements and criteria have been extracted from NFPA 75 Standard for the Protection of Information Technology Equipment and placed in Section 21.14. Several other requirements from other NFPA standards have also been extracted into this Chapter. The information extracted from NFPA 101 The Life Safety Code has been deleted from this chapter due to possible conflicts created with other NFPA 13 requirements.
In Chapter 22 there is now a requirement that where a water flow test is used for the system design the test must be done within 12 months of plan submittal. An annex note has been added recommending consideration of alternate means of determining water supply if there are concerns with drought conditions or other concerns (Paragraphs 22.2.1.1 and A.22.2.1.1). Also, if treatment of the water is needed to prevent corrosion in piping this information must be included on the working plans (Paragraph 22.2.1.2).
Provisions for inactive sprinkler systems that are abandoned-in-place have been included in Chapter 26. Paragraph 26.2 requires sprinklers, hose valves, and alarm devices to be removed. Also, operating mechanisms must be removed from abandoned control valves; and piping and valves must be identified to differentiate them from active systems.
In the 2010 edition there are several important clarifications to purpose and intent of a requirement through the use of more clearly written language and/or explanations in the annex notes. Some clarifications of note are:
The scope statement (paragraph 1.1) clarifies that the requirements of the standard assume sprinkler systems are designed to protect against a single fire only, not an incident involving several points of fire origin. This codifies something that those in the sprinkler industry have more or less assumed for many years.
Paragraph 6.4.6.4 was added to indicate that CPVC fittings are exempt from restrictions on the use of bushings.
The water delivery time for dry pipe systems protecting dwelling units will be 15 seconds (Paragraph 7.2.6.3). A requirement that residential sprinklers also be listed for use in dry pipe systems was added to be consistent with requirements of NFPA 13D and 13R (Paragraph 7.2.6.4).
The minimum 6-foot distance between sprinklers for sidewalls was clarified in that it does not apply to sprinklers protecting soffitted areas beneath sidewall sprinklers (Paragraph 8.7.3.4).
Though it does not appear in the standard, a proposal to allow combustible concealed spaces to take advantage of the Room/Design method was rejected by the committee on the basis that the Room/Design method does not apply to combustible concealed spaces.
In this article we have attempted to address a few of the significant changes in the 2010 edition of NFPA 13, which may be pertinent to you. There are many other changes that have not been discussed here. Please consult this new edition for those changes.
Samuel S. Dannaway, PE, is a registered fire protection engineer and mechanical engineer with bachelors and masters degrees from the University of Maryland Department of Fire Protection Engineering. He is past president and a Fellow of the Society of Fire Protection Engineers. He is president of S. S. Dannaway Associates, Inc., a 15-person fire protection engineering consulting firm with offices in Honolulu, Hawaii and Guam.