Standard Procedure for a fire in a kiln

[Craig Jensen]

Hey all,
I have been asked to write a Standard Operating Procedure for putting out a fire in a kiln.
Do any of you already have one, or any suggestions?
Craig Jensen

[TimothyD]

Hi Craig,
I have never operated any kilns, so others will probably have more experienced based input, but I might suggest, that you call your local fire department and ask them to help you come up with a plan/procedure on what specific steps to take if/when something like this occurs.  I think they might be a valuable resource in your pursuit along with the others on this forum.

Tim

[MichaelM]

Fighting a fire in the building or structure is probably best left to the fire department unless you mill has trained presonnel.  I pasted below what the DKOM says.  You are basically trying to exclude air until the firefighters arrive.

From the Dry-kiln operator's manual (page 216)

Kilns should be checked regularly outside of regular
working hours so that if a fire starts, it can be fought
promptly. A definite procedure should be established
for workers to follow if a kiln fire should occur. The
following procedures may extinguish the fire or will
reduce the spread of fire in a kiln until a firefighting
crew arrives.
1. Install a water sprinkler system and check its operation
regularly.
2. Have fire extinguishers available in the area.
3. Keep all kiln doors closed.
4. Close the ventilators.
5. Shut off the fans.
6. In a steam-heated kiln, saturate the air in the kiln
with steam. If there is a bypass around the steam
spray control, open that valve or, if not, set the wetbulb
control point as high as possible.

[kilnguy]

Funny...we were just having this discussion in our weekly maintenance meeting a couple days ago.  We had a false alarm in our boiler building bringing the fire department to our facility with all their lights/sirens a couple weeks ago.  Visits like that always spur conversations over the probablity/preparation/reaction of those involved.  Someone raised the question of fire in a dry kiln.  I hadn't seen the operator's manual...but our conclusion was about the same as Dr. Milota's.  Fire basically needs 3 things....oxygen, fuel, air (and of course combustion).  To put fire out, you need to eliminate/overcome at least one of these elements.  By closing the vents and shutting off the fans, you take away most of the air, and you overcome the combustion element by introducing water vapor i.e. opening the steam valve.  You may not want to shut off your main electrical source as you will need  it...particularly if your kilns are controlled via a computer/plc that sends your commands to close vents, shut off fans, and turn on steam.  'Pulling a knife switch' or 'killing a main' will eliminate your ability to control these functions.

[Craig Jensen]

Thanks for all the help guys!!
Our fans are on a separate high voltage system, while our controls and thermocouples are all on a low voltage / pneumatic system.  I suppose we would all have to look at how our systems work and make sure our procedures match. . .
Here is what we came up with:
1.   Clean-up is our first line of defense against kiln fires.  Kilns are to be cleaned at least once per month according to the boiler / kiln clean-up plan.  They should also be cleaned any time an operator notices that they are getting excessive sawdust build-up on the floor, or prior to any hot work inside a kiln.
2.   If you are outside of a kiln and suspect or see a fire, do not go inside to put out fire.  Activate steam spray, turn off fans at the disconnect, keep doors closed, and close vents.  Notify supervisor or lead immediately, and monitor kiln control system to determine if fire is out.
3.   Kiln fires are only to be fought by mill personnel if they are smoldering embers, or in the incipient stage.  Fires in these beginning stages can be put out with water can extinguisher, water hose, or appropriate fire extinguisher.  Then clean kiln, and investigate for cause of the fire.  Kiln should not be started back up prior to Supervisor authorization.
4.   If fire is larger than a campfire size, or if lumber is involved in the fire, do not enter the kiln.  THIS IS AN EMERGENCY. Close all doors and vents, turn off fans at the disconnect, and activate steam spray system on all affected kilns.  Notify Boiler / Kiln lead, Supervisor, and call the fire department.

[Kris]

I think one of the most important points to make is to keep the doors and vents closed, let the sprinkler system do its job.  If the lumber is burning out of control and you must open the doors, make sure you pull the trains/carts out and not push them.

[GeorgeCulp]

Our kilns are sprinklered so that gets some water going to the burning area. However, if you have ever been exposed to a fire situation you know that the sprinkler system water will not get to the affected areas very well.

What we do....
1. keep all doors and vents shut
2. trained firemen (who are already familiar with the interior of our kilns), using oxygen back packs, go in and retrack all the baffles.
3. forklift pulls each track out where there is an additional set of high volume sprinklers (deluge system) as well we are ready with our own multuple fire hose system.