P.A.S.S. was the message from Mattapoisett Fire Chief Andrew Murray at a fire extinguisher safety class the department offered at the fire station on Thursday night.

The acronym is a reminder for how to use extinguishers properly: Pull the pin. Aim it at the fire. Sweep the base of the fire while you squeeze the handle.

Murray said there are three types of fires. Class A fires are "ordinary combustibles" like wood, paper, and grass. Class B fires are caused by flammable liquids such as gas and grease fires – often occurring in kitchens. Class C fires are electrical and machine fires, which Murray said are the most common.

For a fire extinguisher used in the home, Murray recommended a dry chemical extinguisher, which can suffocate Class A, B, and C fires. He also said to make sure the extinguisher is Underwriters Laboratories or FM Global approved, which is indicated on the label.

Murray said every home should have two extinguishers. Keeping one in the kitchen near the door is always a good idea. Just don't put it next to the stove.

In the event of a stove or oven fire, he said, "You don't want to put yourself in harm's way. You never want to trap yourself in a room."

Keep the extinguisher by the door, but if its too late to use the extinguisher, don't wait to call 911, said Murray.

"Fires double in size in one minute," he said. Since local fire departments are on-call, it takes firefighters a few minutes to get to the station and then deploy to the fire.

Murray added that it's important to close the door when exiting a room with a fire.

Closing the door deprives the room of oxygen and can help suffocate and contain the fire.

It's best to be prepared now, in case of fire. Make sure the dial on the fire extinguisher is on green, don't reuse extinguishers as pressure can diminish after time, and if the extinguisher is of questionable age, don't take any chances, said Murray.

"When in doubt, throw it out."