March 22, 2019
Fire extinguisher

Fire Extinguishers: A Brief Guide

by Wellness Letter  

Whether you ever have to use one or (hopefully) not, a fire extinguisher is a must-have for all homes (along with smoke detectors and carbon monoxide detectors). Actually, at a minimum, you should have one on every floor, particularly in the kitchen, laundry area, and garage.

What to buy? Here’s a brief guide.

  • All fire extinguishers (about $20 to $80 for home models) come with labels denoting which type of fire they are designed for. Those for Class A fires (ordinary combustibles like paper, wood, textiles, plastics) contain pressurized water; those for Class B fires (flammable liquids like gasoline, oil, kitchen grease, paint, alcohol) and Class C fires (electrical) contain carbon dioxide. Using the wrong extinguisher can make things worse—spraying water on an electrical fire, for instance, can cause an electrical shock to the user. Multipurpose extinguishers (labeled ABC) contain dry chemicals that combat all types of home fires and are good options for most areas—though the best choice for the kitchen is one labeled BC. Newer models also have pictures showing the type of fire they will extinguish.
  • Fire extinguishers come with numbers representing their fire-fighting capacity. A higher number indicates that the extinguisher will put out a bigger fire before running out—but also means it is bigger and heavier, and so may be harder to lift (home models weigh 5 to 20 pounds). The C models have no number rating.
  • The extinguisher should have a label from one of the nationally recognized testing laboratories, showing that it meets safety and performance standards. These include UL (Underwriters Laboratories), ETL (from Intertek), CSA (formerly the Canadian Standards Association), and FM (Factory Mutual).
  • Familiarize yourself with how to use your fire extinguishers before that might be necessary and follow all maintenance instructions provided by the manufacturer, including regularly checking that they are properly pressurized.
  • Fire extinguishers are either rechargeable or for single use. They don’t come with expiration dates, but it’s recommended that you replace unused, non-rechargeable ones 12 years after the date of manufacture. Rechargeable models should be regularly serviced or replaced if parts are damaged or if there is a slow leak, for example.
  • To use, think PASS: Pull (pull the pin to unlock the nozzle), Aim (point nozzle at base of fire), Squeeze (squeeze the handle slowly and evenly), and Sweep (from side to side).

Caution: Use a fire extinguisher only if the fire is small enough to contain (making sure there is a safe exit at your back, should the fire start to get out of control). Otherwise, leave immediately and call 911. If you use an extinguisher, be sure the fire is completely out.

This article first appeared in the UC Berkeley Wellness Letter

Also see How to Buy a Carbon Monoxide Detector.