• Welcome to the new and improved Building Code Forum. We appreciate you being here and hope that you are getting the information that you need concerning all codes of the building trades. This is a free forum to the public due to the generosity of the Sawhorses, Corporate Supporters and Supporters who have upgraded their accounts. If you would like to have improved access to the forum please upgrade to Sawhorse by first logging in then clicking here: Upgrades

History buffs

C

cda

Sawhorse 123
Joined
Oct 19, 2009
Messages
20,963
Location
Basement
Was visiting a museum today and it had a clean agent system in one room

Unknown type agenttwo nozzles in the room

About 15x 40 room

What I have not seen before is the use of a sprinkler head next to each clean agent nozzle

My guess pilot heads. There was no other detection device seen and the room did not have any other sprinkler heads in the room

To me the room would have to have a good size fire before the clean agent dumped unless the fire was near the head
 
Ihe clean agent system activation is probably not head activated, but by a seperate heat detector or by manual activation.
 
Not necessarily, since the 2001 system is considered a total flooding system similar to a water based deluge. The use of pilot heads as detection is acceptable provided it’s listed. The operation of the pilot system is most likely a “dry” pneumatic where a differential is created whereas the sprinkler bulb’s degree setting when fused will release a small amount of air releasing the valve discharging the agent through the two nozzles. These can be as reliable if not more than cross sectional spot heat or smoke detection for environments such as these.

See 4.3.3.2 and 4.3.4.2
 
Last edited by a moderator:
No other detection devices seen

I just question only two heads in such a large room

And the heads were against one wall
 
Thought you were talking about (2) CA nozzles. I would have to question only two pilot heads also for that square footage since in deluge detection the pilot heads are typically on a parallel line with heads next to the open deluge heads. I don't believe the glass bulb has coverage area like RoR or Ft heat detectors.
 
FM

That was my thoughts

It was amo picture taking museum or I would have some shots to post
 
Perhaps an Air Sampling Detection (VESDA) system is triggering the system. These can be well concealed. In a high-value room, one would typically want very early products of combustion detection prior to temperatures getting high enough for heat detection.

EC sidewall sprinkler heads might have that kind of coverage, but these are to provide the "fully sprinklered" coverage. CA is typically seen as suplemental.
 
None seen just two totally separate sprinkler heads right next to the two clean agent nozzles
 
15x40 room could be covered by two extended coverage sprinkler heads that protect the rest of the building, if the clean agent system fails. In most cases the provision of clean agent system does not eliminate the need for sprinklers. Did the heads seem to have a little larger than normal deflectors?
 
Normal size deflectors

No other detection seen in the room

And these two head were against one wall way out of coverage for sprinklers

I am pretty sure they were pilots for the ca just never seen them used on a ca before and seems like you would have a good fire before they activated
 
seems like you would have a good fire before they activated
Click to expand...
That defeats the purpose of a CA system. Might as well spew water all over the place if the ceiling is already 165 deg. There must have been a well concealed "sniffer" detection system.

What did they have for HVAC devices? Might have integrated detection into the HVAC.
 
Ok Cda.....go back and take some "covert" pictures :) I need to know why (the depiction) seems to be a poorly designed protection scheme for this particular area. I could understand what Dr. J suggests with the potentials in air sampling or VESDA detection but I would not suspect heads located against a wall to be EC unless they were side walls and 40' is a strech for horizontal application with just two heads (depending on the model/listing).
 
You must log in or register to reply here.
Top