Gas and Oil Home Heating Furnaces - What is a "Gas Burner Emergency Shutoff"?

Are there requirements for an "emergency shutoff" for a gas furnace?

My furnace has what looks like a standard light switch attached to the incoming power, which I assume is a power shut-off. While it's probably correct, are there requirements I can verify?

While in the the electrical aisle at my local big box store, I noticed steel faceplates painted red and labelled "Gas Burner Emergency shut-off". This seems like a good investment of $0.89 even if not required. If there is ever a question about what the furnace is doing, I could easily describe over the phone how to shut the furnace down until it is looked at. However, the only thing worse than not being able to find a shut-off is to find something labeled as one but doesn't do everything it should. Is there a difference between a "service switch" and an "emergency shutoff"? Is a regular switch good or should this be two pole? Is a label like this required or it doesn't matter? Should the furnace shut off the gas when electrical is shut-off? Is there anything else to verify?

Some codes call for a power off switch at the furnace and one up at the top of say the stairs going down to the basement. So that any one of the switch's will kill the power to the furnace. This will close the gas valve.


ED ;)

To add to Ed's reply which was absolutely correct; the emergency switch should have a red plate as previously described. The service switch should be within reach while working on the burner. In some areas this must also be labeled as an emergency switch.