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By Samuel S. Dannaway, PE,

President, S.S. Dannaway Associates, Inc., Honolulu

FPE Corner

Fire Sprinkler Design Part 2

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publishing them. In certain cases, they may exceed mini-mum codes and, to a lesser extent in some cases, may notmeet minimum code requirements.

It is my opinion that the United Facilities GuideSpecifications (UFGS) located on this website provide thebest guide for a fire sprinkler system specification.

The following represents what I think is a good sug-gested recipe for a properly prepared specification sectionfor a wet pipe fire sprinkler system. The standard specifi-

cation has three major parts. Part 1 Addresses general requirements such as scope

of work, reference publications, design criteria, submittalrequirements, and qualifications.

Part 2 Addresses the products and materials involvedwith the fire sprinkler system.

Part 3 Addresses execution, which normally dealswith the installation, testing requirements, and closeoutrequirements.

Each part should contain the following minimum infor-mation:

Part 1 General RequirementsReferences One needs to identify all pertinent codes

and standards used by the specification. This section alsoshould identify the specific edition of the document whichis to be used. First and foremost would be the applicablesprinkler standard, i.e., NFPA 13 NFPA 13R, or NFPA13D. Other important NFPA documents which may applyare NFPA 14, 20, 24, 25, and 72. There also would be stan-dards for various system components such as ASME andANSI standards for pipe, fittings and AWWA standards forunderground pipe and fittings. Also, the directories of thenationally recognized testing and approval organizationssuch as Underwriters Laboratories Fire ProtectionEquipment Directory and/or Factory Mutual ApprovalGuide should be identified.

Related Specification Sections Here, one may have

references to specification sections for fire pumps, stand-pipes, fire alarms, painting and electrical work.

System Description or Scope of Work A brief para-graph describing the general scope of the project. Identifythe building or area to be protected, if the project is for anew sprinkler system or an existing system being modi-fied, and indicate the extent of coverage (which is usuallythe entire building). The description should include listingrequirements and identify approving authorities.

Sprinkler System Design Requirements This sectionshould define requirements for hydraulic design and seismicprotection. The section also may include sprinkler locationand spacing that is more restrictive than NFPA 13 limita-tions, sprinkler discharge criteria, including design densities

and design areas, hose stream allowance requirements and

The engineers design of a fire sprinkler system mustinclude a basis of design, the contract or bid draw-ings, and a set of specifications. Last month in our

discussion of the engineers design of a fire sprinkler sys-tem we dealt with the project basis of design and the con-tract or bid documents. In this article, we will be dis-cussing the specifications for the fire sprinkler system.

A properly-written sprinkler system specification is thebackbone of the sprinkler system design. Unfortunately, it

is all too common for a poorly edited, or even uneditedsprinkler specification to be submitted as the design. Itsas if the engineer copied the spec from the last job andsubmitted it as is. This can be a cause of several problems.First, because the sprinkler design is performance-based, aproperly prepared specification is essential to obtaining acorrect design. Second, a poor specification creates oppor-tunities for change order seeking contractors to win pro- jects away from competent sprinkler contractors. Third,poor specifications seem to go hand-in-hand with poorlyprepared basis of design and contract drawings. This pro-vides ammunition for those in our industry who feel it issprinkler contractors, not engineers, who should beresponsible for the design of fire sprinkler systems.

The sprinkler specification can take different forms.The specification form chosen depends on the size of thesprinkler system and the requirements of the reviewingauthorities. For a minor project perhaps involving reloca-tion of a few sprinklers, it could be as simple as a fewnotes on a drawing indicating compliance with local codesand identifying the appropriate sprinkler installation stan-dard such as NFPA 13, Standard for Installation ofSprinkler Systems. More often it will be a separate textdocument.

The starting point is normally a guide specification thatcan be tailored to the specific fire sprinkler system design.Many consulting firms maintain their own library of guidespecifications for commercial projects. Also, one can go to

the Master Format website and purchase guide specifica-tions from one of the vendors supporting the MasterFormat. The new Master Format 2004 system is the indus-try standard for construction specifications. This formatexpanded the old 5-digit system from the 1995 version.For example, what used to be Section 13930 FireSuppression Wet Pipe Sprinklers is under Master Format2004 now Section 21 13 13.00 20.

There are also specifications used by various federalgovernment agencies that can be downloaded for free atthe Whole Building Design Guide website of the NationalInstitute of Building Sciences athttp://www.wbdg.org/ccb/browse_lib.php?l=02. Onemust take care when using these specifications as the start-ing part as they have a great deal of information in themthat relates to specific requirements of the federal agencies

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purposes. The engineer should use the Part 2 to prohibitspecific types of products that, in the engineers opinion,have not performed well. For example, many engineers donot permit the use of plain-end fittings.

Regarding the use of proprietary specifications, if theclient or authority having jurisdiction permits the use ofproprietary specifications, then it would be the engineersoption to go with a proprietary specification providedthere is good technical justification for favoring one man-ufacturer over another. In general, it has been my experi-ence with fire sprinkler system design and the resultinginstallation that a non-proprietary specification serves theclient better and has not diminished the quality of theresulting installed system.

Part 3 ExecutionInstallation Practices This section will call for

installation in accordance with NFPA 13 and other applic-able standards. It also can cover items of installation notregulated by the standards that the engineer deems neces-sary. This could include:

1. Concealing all piping in areas with finished ceilings.2. Painting of all exposed sprinkler piping (the engineer

may even want to require painting of all sprinklerpiping).

3. A prohibition against the use of bushings as reducingfittings.

Test Requirements and Acceptance Criteria Thispart also must identify all required preliminary and finaltests and the authority having jurisdiction (AHJ) responsi-ble for recommending acceptance of the system. Theacceptance criteria for a wet pipe sprinkler system is rela-tively straightforward, but we also want to ensure that allpost-installation documents have been provided prior toacceptance; this would include O & M manuals, as-builtor record drawings, spare parts, etc.

Training Part 3 also will contain any trainingrequirements that may be required by the client.

Inspection, Testing, and Maintenance I havefound that requiring the installing contractor to providedITM for the system in accordance with NFPA 25 and theAHJ during the required warranty period to be a valuableservice to clients.

So before the next sprinkler design is due, please take alook at your sprinkler guide specs, make sure they are up

to date and include the necessary provisions to make foran excellent sprinkler system design. Combine a well-written spec with a well-thought-out basis of design andproperly prepared contract drawings and the chances of asuccessful installation with minimal construction issueswill be greatly improved. I

Samuel S. Dannaway, PE, is a registered fire protection engi-neer and mechanical engineer with bachelors and mastersdegrees from the University of Maryland Department of FireProtection Engineering. He is past president and a Fellow of theSociety of Fire Protection Engineers. He is president of S. S.

Dannaway Associates, Inc., a 15-person fire protection engineer-ing consulting firm with offices in Honolulu, Hawaii and Guam.

water supply data. If some or all of this information is con-tained on the drawings, then it may be better for this sectionto refer to the information on the drawing rather than repeat-ing it and risking a mistake that could create a conflict with

the drawings. This is a good general rule to follow for avoid-ing conflicts between specifications and drawings.

Submittals The submittal requirements should beclearly identified. This includes the parties (the engineer,building department and/or fire department) the contractormust have review and approve the submittals before instal-lation can proceed. In addition to the minimum require-ments for working drawings, hydraulic calculations, andmeeting the requirements of Chapter 22 of NFPA 13, thespecification also should require the submittal of productdata. The product data must have sufficient technical infor-mation to allow reviewers to determine compliance withthe specifications, and where there are choices betweendifferent model, part or style numbers, the cut sheetsshould be annotated to identify which specific items arebeing provided. This section also will identify the submit-tal requirements that occur later in the project includingtest plans, test reports, i.e., NFPA 13 Contractors Materialand Test Certificate for Underground Piping and theContractor's Material and Test Certificate for AbovegroundPiping; operations and maintenance manuals, as-builtdrawings, and spare parts. This section should also containa provision prohibiting partial submittals.

Installer Qualifications The contractors qualifica-tions may include a level of experience and licensesrequired by the jurisdiction. One also may wish to includecertification requirements for the sprinkler contractors lay-out technician. One way to do that is to require the layout tobe performed by a NICET Technician with minimum Level3 certification in Automatic Sprinkler System Layout.

Part 2 ProductsThis section is used to specify requirements for all the

various components in the sprinkler system. This wouldinclude that portion of the underground piping system thatmay fall within the purview of these specifications. Above-ground piping components include pipe, fittings, hangersand supports, seismic bracing, branch line restraints, valves,alarm valves, alarm valve trim, sprinklers, fire departmentconnections, backflow prevention devices, drains, signage,spare sprinkler cabinet and relief valves.

In general, all components must be listed or approved bya nationally recognized testing laboratory such as UL or FM.As with design criteria, one must make sure product

specifications do not conflict with information on thedrawings. A common conflict arises when specificationsand drawings allow different kinds of piping materials ordifferent types of sprinklers.

Because a certain fire sprinkler product complies withNFPA 13, and is properly listed, does not necessarilymean that the product must be permitted to be used. Theengineer has the option to require a higher standard of per-formance, as indicated by their experience and knowl-edge. It is also important to be aware of any specialrequirements of the client that exceed the minimums

established by NFPA 13. This could include limitations ofthe type of pipe and fittings that will be allowed or the useof concealed, recessed pendent sprinklers for aesthetic

FireProtectionContinued from page 26

The views and opinions expressed in this column are those ofthe author and do not reflect those ofPlumbing Engineernor its

publisher, TMB Publishing.