Mixing ordinary and intermediate temperature fire sprinkler heads in light hazrd occupancy 1

[tebbensm]

Can BOTH ordinary and intermediate temperature fire sprinkler heads be indiscriminately installed in a common light hazard occupancy? I know that sprinkler heads within a specified distance of heat producing equipment may need to be intermediate temperature, but can a contractor install BOTH ordinary and intermediate temperature heads in the same space, though the intermediate temperature head is not required?

 

[SprinklerDesigner2]

You can mix where called for but if possible I would avoid it.

To avoid any problems we've adopted a policy to use intermediate temperature sprinklers throughout all light and ordinary hazard buildings. This way we can almost ignore the placement of HVAC diffusors and such.

8.3.2.1* Unless the requirements of 8.3.2.2, 8.3.2.3, 8.3.2.4, or 8.3.2.5 are met, ordinary- and intermediate-temperature sprinklers shall be used throughout buildings.

from the commentary

Traditionally, ordinary-temperature sprinklers have been required throughout a building unless the requirements of 8.3.2 required intermediate- or high-temperature sprinklers to be used. However, many buildings are built without suspended ceilings, resulting in a mix of ordinary with the intermediate temperature-rated sprinklers needed around heating diffusers and other heat-producing areas. Since the response time of quick-response intermediate-t emperature sprinklers is not that different from ordinary-temperature standard-response sprinklers, the standard now groups ordinary- and intermediate-temperature sprinklers together and allows intermediate-temperature sprinklers throughout the building, reducing the need for multiple types of sprinklers.

Intermediate in everything solves a lot of potential for problems.

 

[stookeyfpe]

The other issue is the sprinkler's RTI. Mixing of QR with SR sprinklers increases the potential of sprinkler skipping, resulting in an excessive number of sprinklers operating. This is more problematic if QR sprinklers were used to reduce the sprinkler design area.

 

[3cio]

Hello!

First, I assume that NFPA 8.3.2.2, 8.3.2.3, 8.3.2.4, 8.3.2.5 does not met with regards on your situation since you said that intermediate temperature sprinkler is not required.

Temperature ratings of a sprinkler are used for the following; A) To keep sprinklers from operating accidentally if installed in a high ambient temperature area & B) to control the number of sprinklers operating in the design area.
--Since different temperature rating of sprinkler is installed within the same space, there is a possibility that the sprinklers will not actuate as per it was intended to in which it will contradicts the intention per the above (B).

My opinion regarding the commentary;
"Since the response time of quick-response intermediate-temperature sprinklers is not that different from ordinary-temperature standard-response sprinklers, the standard now groups ordinary- and intermediate-temperature sprinklers together and allows intermediate-temperature sprinklers throughout the building, reducing the need for multiple types of sprinklers."
is that this statement is more likely applicable other than light hazard occupancy because:

1) the comparison is between a quick-response intermediate-temperature sprinklers VS. ordinary-temperature standard-response sprinklers in which light hazard occupancy is calling for a quick response sprinklers for new installation.


I agree to SprinklerDesigner2 that "Intermediate in everything solves a lot of potential for problems".

thanks,

 

[tebbensm]

I should offer some more information on my query. The building is a small health clinic. The sprinkler contractor is starting to practice installing ALL intermediate temperature FR heads in all of their buildings. In this building however, they decided to use the rest of their ordinary temperature FR heads and then filled in with intermediate temperature FR heads. The owner, my client, does not like it. The contractor says he is allowed to do it by NFPA. I do not design fire suppression systems, but specify as performance system to be designed by the FS contractor. SO, in some rooms he installed a mix of ordinary FR and intermediate FR heads? Perhaps I will have to tighten up my performance specification?

 

[SprinklerDesigner2]

In this building however, they decided to use the rest of their ordinary temperature FR heads and then filled in with intermediate temperature FR heads. The owner, my client, does not like it.

I'm just a layout technician but mixing sprinkler temperatures without specific reasons just smells bad to me and for that reason alone I would never do it.

If I had any say I wouldn't accept it. The owner is a customer and not someone to pile left over garbage on.

To me this is very upsetting. Let's call it a small 100 head job so we're most likely talking in the range of $15,000 (no underground or backflow in this price) and a contractor wants to mix heads to offset a couple hundred dollars? In fact he isn't offsetting any monies he's just dumping what he views as garbage.

I've taken to using intermediate temperature sprinklers on all my OH-1 and OH-2 projects but I've kept to using standard temperature sprinklers in LH just because it's all I've ever done and I feel better about it.

What did the contractor do with his AHJ approved drawings. did he show different temperatures or did he show all intermediate then do what he wanted? I'd look, if he showed all intermediate, or ordinary, I'd hang him with his own drawings and make him do exactly what he showed.

I'm very proud to have been a member of the fire sprinkler industry for over 40 years and this kind of penny anti (however it is said) BS is very upsetting to me.

 

[3cio]

Hello!
Good day!

In my opinion;
Contractor could say that NFPA doesn't prohibit him to do so as you said, but installing same type of sprinkler is also as per NFPA.
Therefore, owner could insist the same and the contractor should follow.
Reason is:
By definition, AHJ is an organization, office, or INDIVIDUAL responsible for enforcing the requirements of a code or standard, or for approving equipment, materials, an installation or a procedure. Also per A.3.2.2 " - the property owner or his or her designated agent assumes the role of the authority having jurisdiction; "


In addition to stookeyfpe, refer to below:

 

[Jondoeiowa]

What did the contractor do with his AHJ approved drawings. did he show different temperatures or did he show all intermediate then do what he wanted? I'd look, if he showed all intermediate, or ordinary, I'd hang him with his own drawings and make him do exactly what he showed.

Fully agree with SprinklerDesigner2, check their approvals from AHJ and their submitted shop drawings and if they do not show the varied sprinkler temps that were installed, request they follow the documents.

I'm only a layout technician, but this is something we would never do within our company.