Sprinklers design area

[khaled eltaweel]

Sprinklers design area for light hazard if sprinklers positioned below wood joists is?

The design area and density for Class III palletized storage have height 11m and high temp. CMDA k16.8 sprinkler is?

 

[SprinklerDesigner2]

Maximum is 1,500 sq ft (139.3 sq meters) for wet systems and 1,950 sq ft (181.2 sq meters) for dry systems both assuming the ceiling is >20'-0" high.

 

[khaled eltaweel]

Appreciated your response sprinklerdesigner2 .... the wood joists will not affect the sprinklers design area ? i searched deeply in NFPA 13 but i did not found that wood joists have effect on sprinkler design area

 

[khaled eltaweel]

hi sprinklerdesigner2 the below screenshot should help to solve question no 2? i trying to solve this question

 

[TravisMack]

CMSA sprinklers often confuse people on design area. It is not a typical density / area process. You take the number of sprinklers x the MAXIMUM area of coverage per sprinkler. So, if you are using 16.8 CMSA as your table indicates, you have 15 sprinklers for wet and 25 for dry. Since the max area of coverage for CMSA is 100 sq ft then the minimum design area is 1500 sq ft for wet and 2500 sq ft for dry. Also, the minimum length of the design area is 1.2 X SQRT(design area). Be sure to get the proper shape of the design area.

To answer the other question about the wood joists, that will only impact maximum area of sprinkler depending on construction type. Also, if you have non-sprinklered concealed combustible spaces, that could trigger a design area requirement of 3000 sq ft.

Travis Mack, SET, RME-G,
MEPCad, Inc
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