Shaking fire extinguishers. Is it too late?

[MastUndSchotbruch]

I was told recently that one is supposed to shake fire extinguishers (the usual powder type) once in a while to prevent the powder settling at the bottom and caking. I have a half dozen fire extinguishers on the boat (yes, I am a bit paranoid in this regard), some of them many years old. And yes, all of them show the gauge in the 'green' range (I had one or two that slowly moved out of the green and they were promptly replaced).

So, I took some of them off their brackets and and shook them. I expected to feel some movement in them when I turn them upside down etc but nothing, even with prolonged (a minute or so) shaking.

Is this a problem? Should I feel the powder moving inside? Anything I should do?

[Rangernewell]

Usually once a month I turn mine upside down and tap them with a rubber mallot...If you flip them quickly you should feel the weight shift from on end to the other.They sometimes cake up from sitting for a long period of time. You can hit them pretty hard with the mallot (RUBBER) without any worries.

[aeventyr60]

Maybe you should take one of those out and fire it off to see if they work our not? I have been doing the rubber mallet thing for quite some time, wondering if they will work....

[Lake Superior Sailor]

Its more about the expiration date then anything. I have recharged fire extinguishers & that powder doesn't cake unless wet and it's charged with dry gas. I have not seen a problem..Dale

[Squidd]

The extinguisher maintenance company would just Rap them with the rubber mallet and check the gauge for green when they did yearly recert at the shop...

I do not think the cans themselves have a expiration date, but don't quote me on that...

[tommays]

When I refit Seafever I Tested all the outdated units into plastic bags and they all fired 100 % and I can assure those were never taped for at least 20 years But they were top shelf Units

[Lake Superior Sailor]

All tanks get hydrostatic tests on a time table---Dale

[Rangernewell]

Sorry ...I should of used a different word than (Cake) as sailor mentioned....Couldn't think of one though.......SETTLE ??????

[bassviking]

Rangernewell is right on the money in regards to flipping and love taps with a mallet. I've been in the fire service for a while in various military and government installions around the world and part of every fire inspection I ever did was to check the extinguishers. Here are the things you should check on your ABC or BC extinguishers:

1. Make sure the guage is in the green. This ensures there is enough pressurized nitrogen in the can to expel all of the dry chemical.

2. Tip it over and back a few times to feel if the dry chem is loose and flowing. This ensures that ithe dry chem has the chance to get out.

3. Make sure the safety pin is secured. This prevents accidental discharges. One thing to note here. DO NOT USE ZIP TIES TO SECURE THE PIN. Zip ties are too strong for the average joe to yank out. Fire codes require that the tie be able to break with from 2-4 lbs of force. Enough to hold the pin in but light enough for anybody to break when needed. Also, don't use masking tape, duct tape, rubber bands, twine, string, wire, or any of the multitudes of insane things I've seen on fire extinguisers. Go to your local FD or fire extinuisher service company and get the real deal extinguisher seals. They're like a dime a dozen.

4. Check the hydrostatic test date. (if there is one) Metal can extinguishers have dates stamped near the top or on the bottom of the extinguishers. Depending on the type of container they have to be tested every 5 or 12 years for their ability to hold pressure. If the date you find stamped is more than 5 years ago its best to get it checked. I'm fairly certain plastic containers don't have these as most of them are use once and throw away types.


Also if you happen to have a Halon extiguishers just make sure its in the green. Halon is liquid and doesn't cake. If you ever fire it off make sure to leave the area immediately. Halon displaces oxygen and will suffocate you. Its also super nasty for the environment.

[Lake Superior Sailor]

Must have yearly inspection sticker.....Dale