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Maximim size room for CPVC pipe in Ordinary 1?

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fpst

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Jan 20, 2012
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Ordinary 1, NFPA 13 or 13R looking for either scenario:

What is the maximum OH1 sq. ft. room you can install CPVC pipe in? I found 400 sq. ft. in NFPA 13 and 13R, but seem to recall reading 800 sq. ft. somewhere. Wondering where this 800 sq. ft. might have come from.
 
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Yes NFPA 2013 says 400 ft2. I don't see anywhere saying 800 ft2 other than the definition of small room.

 
No date on this:


BlazeMaster® CPVC Now in Ordinary Hazard Applications

Change: An exception to Section 3-3.5 of NFPA 13 was implemented in its 1999 edition which allows BlazeMaster® CPVC to protect ordinary hazard rooms of otherwise light hazard occupancies where the room does not exceed 400 ft2. Use the same installation guidelines as used for light hazard installations for both concealed and exposed ordinary hazard applications.

Benefit: Fewer transitions between BlazeMaster® piping and other piping systems or materials.

Examples: Light hazard buildings such as schools, apartments and hotels that contain ordinary hazards rooms such as storage areas, laundry facilities, or mechanical rooms that do not exceed 400 ft2.

 
You are confusing small room size with space to protect in OH with blazemaster. Remember, these spaces are not just room size, but all spaces together. If you have a laundry of 300 sq ft and a storage room of 120 sq ft right next to each other, that is 420 sq ft and you can't use CPVC above that area.

Travis Mack
MFP Design, LLC
"Follow" us at
 
It's interesting how the scope of these rules is lacking

If you have two janitor closets 210 sq. ft. each, in an otherwise light hazard area, adjacent to each other, with a wall between them that does NOT go all the up
If you have two janitor closets 210 sq. ft. each, in an otherwise light hazard area, adjacent to each other, with a wall between them that DOES go all the up
If you have two janitor closets 210 sq. ft. each, in an otherwise light hazard area, 10 ft. from each other separated by a light hazard room

3 scenarios. The standard (13-2013) literally says:
6.3.7.6 Nonmetallic pipe listed for light hazard occupancies shall be permitted to be installed in ordinary hazard rooms of otherwise light hazard occupancies where the room does not exceed 400 sq. ft.

Since each janitor closet is a room, one would assume not to calculate the areas together. Using common sense, one might calculate the areas together based on if there is no light-hazard area separating them. It might also change depending on if walls go all the way up or not.

What happens if you have a 2 ft. light hazard separation instead of 10 ft. separation? What happens if it's 1 inch? What happens if you have 20 janitor closets all separated by 400' of light hazard areas, or 20 janitor closets adjacent to each other, or 20 janitor closets separated by 1 ft. of light hazard areas.

I understand that given experience and common sense, one can usually arrive at an answer most AHJ's would agree with, but it just seems impossible to get an accurate interpretation when the intent/background info of each rule is missing.
 
I'd agree with what you originally said, as it makes the most sense, but we all know the geometry of an office can get crazy and lots of "alternative" scenarios pop up - what if two 210 sq ft areas are adjacent to each other only at the corners - meaning 1 pixel is touching. In a cluttered hotel this can in my experience. It's just an underlying problem of rule making - multiple interpretations.
 
I looked back at the data sheet. It does say room. So, I guess as long as they are separate rooms you should be OK. It must have been one of those things where an AHJ had the interpretation that it couldn't exceed 400 sq ft all together and I didn't have the time or energy to fight it. I guess that stuck in my head.

Travis Mack
MFP Design, LLC
"Follow" us at
 
Easy now,

A room is a room is a room. It ends at the ceiling. The proper term is compartment. See 3.3.6 of the 2010 edition.
If you do not have 4 walls and a ceiling, then it isn't a room. You would then expand your room search until you arrived at 4 walls and a ceiling. (The number 4 is informational only.)

Not to be confused with "Dwelling Unit", which is a group of compartments (rooms) used for living..., etc.. (3.3.8 (2010))

I once had to fine line a room @ the wall. I eventually won out with it does not go to the centerline of the wall (thereby making me add another sprinkler). It goes to where the stuff inside can be placed.

Don't read this stuff too hard. It can cause headaches....

R/
Matt
 
6.3.7.6 Nonmetallic pipe listed for light hazard occupancies shall be permitted to be installed in ordinary hazard rooms of otherwise light hazard occupancies where the room does not exceed 400 sq. ft.

One could argue that this means the ordinary hazard rooms have to be surrounded by light hazard occupancy. Otherwise, where do you draw the line? If a building is 51% light hazard, and 49% small (less than 400 sq ft) ordinary hazard rooms, does that technically fit the rule, regardless if the rooms are adjacent or separated?

There's a lot of (too much in my opinion) room for (mis)interpretation
 
How they should be constructing these rules I think (just one way, could change depending on intent but is more unambigious):

If nonmetallic pipe is listed for light hazard occupancies then the nonmetallic pipe can be installed in ordinary hazard compartments if all of the following requirements are met:
(1) the ordinary hazard compartment's floor area is less than or equal to 400 square feet and;
(2) the fire-separated floor area enclosing the ordinary hazard compartment(s) and the light hazard areas consists of at least 70 percent light hazard floor area.

NOTE 1: A fire-separated floor area is defined as any x hour separation on all sides. (x being whatever is normal for multiple floors, outside walls, etc, I dont know the number yet)
NOTE 2: A compartment is defined as at least 3 walls which complete enclose a boundary, a solid floor, and a ceiling.

 
I think you are still looking too hard.

You would have to go to the building code and start the process.
"B" Occupancy (Office)
Office per Standard (NFPA 13) = Light Hazard Occupancy (5.2)
Janitor's Closet per Standard (NFPA 13) = Ordinary GR I (5.3.1.1)

5.1.2 Occupancy classifications shall not be intended to be a
general classification of occupancy hazards.


So yes, if you have 51/49, technically that fits. It is the Class use of the building referenced, not the individual room.

R/
Matt
 
or rather,

If nonmetallic pipe is listed for light hazard occupancies then the nonmetallic pipe can be installed in ordinary hazard compartments if all of the following requirements are met:
(1) each ordinary hazard compartment has a floor area less than or equal to 400 square feet and;
(2) the fire-separated floor area enclosing the ordinary hazard compartment(s) and the light hazard areas consists of at least 70 percent light hazard floor area.

NOTE 1: A fire-separated floor area is defined as any x hour separation on all sides. (x being whatever is normal for multiple floors, outside walls, etc, I dont know the number yet)
NOTE 2: A compartment is defined as at least 3 walls which along with a solid floor and a ceiling completely enclose a three-dimensional boundary.


unambiguity is hard
 
@Matthew
Does that mean that a office inside a storage warehouse can't use CPVC in a 100 sq ft OH1 janitor closet when the rest of the office (lets say 5000 sq ft) is light hazard because the building (storage warehouse) itself isn't light hazard?
 
found this in NFPA 13 2013,

"5.2 Light hazard occupancies shall be defined as occupancies or portions of other occupancies where the quantity and/or combustibility of contents is low and fires with relatively low rates
of heat release are expected."

which tells me that in the storage warehouse example, the office building itself could be considered a light hazard occupancy because it's a portion of another occupancy (whatever the storage warehouse is).

then applying
"6.3.7.6 Nonmetallic pipe listed for light hazard occupancies shall be permitted to be installed in ordinary hazard rooms of otherwise light hazard occupancies where the room does not exceed 400 sq. ft."

could be argued that the ordinary hazard rooms (janitor closet) is a part of the light hazard occupancy that is the warehouse office (as common sense would imply)

in which case I think everything would be "technically ok" too
 
Bingo!

To further muddy the water let's go back to your 51/49...,

Travis runs a very successful Design and Consulting business.
So much so, that he is building a new 100,000 SQ FT corporate headquarters.
His 1000 SQ FT office is located dead center of the building. A 1000 SQ FT corridor leads from the front door to his office.
The remainder of the building is 246 Janitor's Closets @ 398.374 (+/-) SQ FT each. One for each of his janitors.
He wrote the spec himself stating only CPVC is allowed.
Is CPVC allowed?

R/
Matt
 
I'd say that the overall 100,000 sq ft headquarters would be considered OH1, so the OH1 janitor closets within it wouldn't be "within otherwise light hazard occupancy"

so no, CPVC would only be allowed within the 1,000 sq ft office and corridor

however if you had a 100,000 sq ft office that happened to have 246 janitor closets @ 398.374 +/- sq ft each within the light hazard office, then you could say cpvc is allowed because the OH1 rooms are "within otherwise light hazard occupancy", even though the light hazard isn't the majority of the area.

probably this goes against the intent - but it wouldnt be the end of the world either. cpvc piping is cooled by sprinkler water discharge to maintain structural integrity. in less than 400 sq ft rooms, any sprinkler discharge because of a fire are going to cool that tiny room in no time, along with the cpvc piping, keeping the piping intact. the 4 walls and ceiling/floor act as "anti-fire construction method", so your sprinkler requirements aren't as stringent, but it's an extreme example and one the AHJ probably wouldn't buy
 
p.s. if Travis would sweating like the hulk and destroying everything he grips with his hands all the time he wouldn't need 246 janitors to clean up the destruction
 
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