If you ever need to use your fire extinguisher, you probably want it to work. The powder in some extinguishers can settle and harden at the bottom, making them unusable. To prevent this, conduct some quick maintenance every six months or so.
Photo by Shardayyy.
Home renovation site Make It Right reminds us that extinguishers need an annual check-up to make sure they still work properly. You want to check that the pin and tamper seal are intact and that the pressure is still in the green. Beyond that, here's what they suggest:
Tip it upside down. The agent inside the extinguisher can settle at the bottom — it has the consistency of flour and can easily get packed over time. Turn the fire extinguisher upside down a few of times to break up the agent inside.
I first read this tip via Reddit, where they also suggest hitting the bottom of the extinguisher sharply with your hand. Other sources say the same, and some suggest hitting it with a rubber mallet. Generally, your palm should do the trick, and you probably want to make sure to check your extinguisher every six months to a year. For more detail head to the link below.
Fire Extinguishers [Make It Right]