Class K extinguishers and the placard beside an automatic system
The portable and the hood system work as a pair, in a set order. The placard that says so is small, cheap and almost always missing.
In a commercial kitchen the portable extinguisher and the hood suppression system are meant to work as a pair, and in a set order. NFPA 10 says which extinguisher goes there, how far away it can be, and the sign that goes with it. NFPA 96 explains why the order matters.
A Class K is a backup, not a substitute
A kitchen with a cooking grease hazard needs a Class K extinguisher within a short walk of the appliances (NFPA 10 Chapters 5 and 6). It backs up the suppression system. It does not replace it: the hood over equipment that produces grease laden vapors still gets its own listed suppression system (NFPA 96 Chapter 10).
This follows the general rule in NFPA 10 Chapter 5: the extinguisher is selected for the hazard actually present, and the hazard classification also drives how far apart extinguishers can be.
Measure the walk
Travel distance to an extinguisher is capped, and the cap depends on the hazard class and the extinguisher rating (NFPA 10 Chapter 6). In a kitchen, travel distance is the path you walk around the equipment, not a straight line through it.
The placard
Where a hazard is protected by an automatic fire protection system, a placard goes near the extinguisher stating that the automatic system is to be actuated before the extinguisher is used (NFPA 10 Chapter 6).
The reason is the shutdown. Operating the hood system shuts off fuel and power to every appliance under the hood (NFPA 96 Chapter 10). A portable extinguisher does not. Putting a fire out while the burners keep running does not solve anything.
The trigger for the placard is the automatic system, not the Class K extinguisher itself. The same requirement applies wherever a portable sits alongside an automatic system, in a kitchen or anywhere else.
From the field
The placard is a small item, almost always missing, and trivially cheap to put right. It is also the one thing on the wall that tells a cook what to do first.
The pull, the extinguisher and the sign together
On a walkthrough these three belong in the same look, because they are what a cook reaches for in the first seconds of a fire.
| Item | What to check | Where it comes from |
|---|---|---|
| Class K extinguisher | Present, within a short walk of the appliances, measured as walked | NFPA 10 Chapters 5 and 6 |
| Placard | Near the extinguisher, saying the automatic system is actuated first | NFPA 10 Chapter 6 |
| Manual pull | On the way out of the cooking area, at a reachable height, far enough from the appliances to reach during a fire | NFPA 96 Chapter 10, NFPA 17A |
| Mounting and visibility | Can be lifted down, bottom clear of the floor, visible or its location marked | NFPA 10 Chapter 6 |
From the field
Stored material in front of an extinguisher is the same finding as a blocked pull station, and just as common. A pull mounted behind the fryer line is unusable at the moment it matters. Stand where the cook stands and see whether you can reach both.
Coordinate the trades and check the licenses
Where the hood system is connected to the building fire alarm, kitchen suppression work and fire alarm work meet at the same point. If the kitchen contractor and the fire alarm contractor are different companies, coordinate with the fire alarm vendor before working on the hood system, so the fire alarm side knows it is being worked on, and test the connection between the two together.
Licensing is often separate for each trade. Depending on the state and the jurisdiction, kitchen suppression, fire alarm and electrical work can each need their own license, and the work on a specific system can call for training and certification on that system. Make sure whoever does each part of the job is properly licensed, trained and certified for it.
From the field
One company holding every license does not remove the coordination. The person on the fire alarm side still needs to know the hood system is being worked on before anyone touches it.
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