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Type I Hood fan shut down?

mtlogcabin

mtlogcabin

SAWHORSE
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Oct 17, 2009
Messages
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Location
Big Sky Country
We have some inconsistency in shutting down Type I Hood ventilation system upon activation of the suppression system. Some jurisdictions shut down the entire system others just the make up air and leave the exhaust on regardless of the type of extinguishing sytem. Our jurisdiction has been under the IFC since 2002 while every one else in the state remained under the UFC. They are now adopting the 2009 IFC.

This was all I could find

2006 IFC 904.11.3.1 Ventilation system.

Commercial-type cooking equipment protected by an automatic carbon dioxide extinguishing system shall be arranged to shut off the ventilation system upon activation.

Our own FD required the supply to be shut down and the exhuast to remain running but I can not find a code section to back this up
 
Since CO2 extinguishment is mainly by oxygen reduction and a little cooling, I would vote for shutdown of exhaust and supply (what that code section says) to allow the concentration of CO2 to stay as high as possible for as long as possible in the hood and duct.
 
here's another opinion" calif mech code(u.m.c.) 511.2.3 "a hood exhaust fan shall continue to operate after the extinguishing system has been activated..."
 
IFC (Based upon NY)

610.4 Inspection and maintenance. Commercial kitchen exhaust hoods shall be inspected and maintained in accordance with NFPA 96.

NFPA 96

8.2.3 Exhaust Fan Operation.

8.2.3.1 A hood exhaust fan(s) shall continue to operate after

the extinguishing system has been activated unless fan shutdown

is required by a listed component of the ventilation system

or by the design of the extinguishing system.

8.3.2 When its fire-extinguishing system discharges, makeup

air supplied internally to a hood shall be shut off.
 
I see now see where the confusion has come from because the ICC does not reference NFPA 96 in the IBC, IFC or the IMC.

The ICC's new certification for FK Pre-engineered Kitchen Fire Extinguishing System Technician list it as a reference needed for the test.

Now that makes sense to test an inspector on a document he is not authorized to use.:mad:
 
A code-compliant CO2 system would have a damper in the ductwork, again the assumption is to keep the CO2 concentration elevated. If there is indeed a damper at the top or bottom of the duct it might not matter if you leave the exhaust on, but it says to shut the system down.

[F] 904.3.3 System interlocking.

Automatic equipment interlocks with fuel shutoffs, ventilation controls, door closers, window shutters, conveyor openings, smoke and heat vents and other features necessary for proper operation of the fire-extinguishing system shall be provided as required by the design and installation standard utilized for the hazard.

904.11.3 Carbon dioxide systems.

When carbon dioxide systems are used, there shall be a nozzle at the top of the ventilating duct. Additional nozzles that are symmetrically arranged to give uniform distribution shall be installed within vertical ducts exceeding 20 feet (6096 mm) and horizontal ducts exceeding 50 feet (15 240 mm). Dampers shall be installed at either the top or the bottom of the duct and shall be arranged to operate automatically upon activation of the fire-extinguishing system. When the damper is installed at the top of the duct, the top nozzle shall be immediately below the damper. Automatic carbon dioxide fire-extinguishing systems shall be sufficiently sized to protect all hazards venting through a common duct simultaneously.
 
from NFPA 17A 2002 edition

4.4.3.5 Exhaust fans and dampers are not required to be shut down on system actuation as the systems have been tested under both zero- and high-velocity flow conditions.

plus as alway install per manufacutre, which i sure states to let the exhaust ru, but not sure if they tell you to turn the make up off??
 
cda said:
from NFPA 17A 2002 edition 4.4.3.5 Exhaust fans and dampers are not required to be shut down on system actuation as the systems have been tested under both zero- and high-velocity flow conditions.

plus as alway install per manufacutre, which i sure states to let the exhaust ru, but not sure if they tell you to turn the make up off??
Click to expand...
17A is for wet chemical systems and does not apply to the OP.
 
17A is for wet chemical systems and does not apply to the OP.
Click to expand...
I was looking for something in the code that was generic to all systems (like NFPA 96) so I would think 904.11 would get me to each specific system since I can't use NFPA 96 unless the manufactures installation instructions reference it.

904.11 Commercial cooking systems.

The automatic fire-extinguishing system for commercial cooking systems shall be of a type recognized for protection of commercial cooking equipment and exhaust systems of the type and arrangement protected. Preengineered automatic dry- and wet-chemical extinguishing systems shall be tested in accordance with UL 300 and listed and labeled for the intended application. Other types of automatic fire-extinguishing systems shall be listed and labeled for specific use as protection for commercial cooking operations. The system shall be installed in accordance with this code, its listing and the manufacturer’s installation instructions. Automatic fire-extinguishing systems of the following types shall be installed in accordance with the referenced standard indicated, as follows:

1. Carbon dioxide extinguishing systems, NFPA 12.

2. Automatic sprinkler systems, NFPA 13.

3. Foam-water sprinkler system or foam-water spray systems, NFPA 16.

4. Dry-chemical extinguishing systems, NFPA 17.

5. Wet-chemical extinguishing systems, NFPA 17A.
 
I believe your on the right track MT. Personally I have 96 so the only way to get there IMHO is using that and and the specific system manufacturer's material.

BTW congrats: TJ it was a great game ;)
 
Our own FD required the supply to be shut down and the exhuast to remain running but I can not find a code section to back this up

from NFPA 17A 2002 edition

4.4.3.5 Exhaust fans and dampers are not required to be shut down on system actuation as the systems have been tested under both zero- and high-velocity flow conditions.

I think this answers half your question

icodes allow you to reference other codes 102.7 IFC 2002 edition

also from NFPA 96 : 2008 edition

8.3.2 When its fire-extinguishing system discharges, makeup air supplied internally to a hood shall be shut off.

suggest you call someone you trust in the fire extinguisher business and ask them the question see if it is in the manfacture installation instructions also.
 
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IBC 904.11.2: System interrconnection. The actuation of the fire suppression system shall automatically shut down the fuel or electrical power supply to the cooking equipment. The fuel and electrical supply reset shall be manual.
 
The manufactures of UL 300 suppression systems have their systems tested and listed to control a fire with the exhaust fans on or off. But, if the exhaust fan is on, the following benefits are noted

1. The smolke is pulled up the duct, increasng visibliity

2. The heat is pulled out to the kitchen, increasing comfort of the fireman. I will say I never noticed how hot a fire was while I was fighting it, so this point is moot.

2. The suppression agent is pulled up the duct, controlling any fire in the duct better.

Intake air is different, we do not need any more oxygen delivered to the fire.
 
Folks, the OP is questioning CO2 suppression...UL300 does not apply...the ventilation system will affect the concentration of CO2...wet chemical systems are different...
 
I don't know if his specific question was regarding CO2 systems or the only code section he could find referenced CO2.......
 
""""""""""""""""" I was looking for something in the code that was generic to all systems (like NFPA 96) so I would think 904.11 would get me to each specific system since I can't use NFPA 96 unless the manufactures installation instructions reference it. """"""""""""""""""
 
The point is that even if you could use 96, the suppression standard could trump it. It's not always as easy as we would like it to be.
 
I was refering to all systems.

When I did an I-Quest word search the CO2 system was the only one that popped up.

I see where I need to order a couple of NFPA Standards next week. They will probably put my budget in the red for the end of the fiscal year :cry:

Thanks for all the help
 
Wouldn't the running exhaust fan pull the suppression agent up the vent instead on letting it suppress the fire at its source?
 
well then look in IBC Sec 904.3.3 System interlocking.

904.11 items 1-5 shall be installed in accordance with the referenced standard.. NFPA 12,13, 16 17, 17a
 
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