A friend recently gave a dire warning that a fire extinguisher left in a kitchen corner, undisturbed, for many years will not work, because the chemicals will settle to the bottom and form a cake that will not dispense. He said you need to shake a fire extinguisher every few months to prevent this.
Some Googling shows this advice repeated elsewhere, but no fire extinguisher manufacturer mentions anything about it… just reminders to check the pressure gauge weekly.
What’s the straight dope?
Listen to the manufacturers.
I had a kitchen fire extinguisher sit ignored in a corner for over 10 years. When we finally needed it in an emergency it worked flawlessly.
The people making them know these things sit around for years before being used. Why shouldn’t they take that into consideration when making them and/or instructing owners on how to maintain and use them?
At my yesterjob, There were some extinguishers that were periodically turned upside down and rapped with a rubber mallet by the guy who maintained them. They were maybe a different class than kitchen extinguishers.
I was chit chatting fire captain just a few weeks ago and happened to mention that I picked up a few (more) fire extinguishers for my house. We were talking about the expiration dates on them since their not the types that are meant to be brought in for annual checks. He said that he has the same ones at his house and then followed it up with 'do me a favor, once or twice a year, turn them upside down and give them a shake otherwise all the powder turns to concrete on the bottom".
The ones I already had for a few years, I did that with. After about 45 seconds, I could hear all the powder start falling. Now when I do that, I can hear it move right away, it sounds like sugar falling instead of brown sugar breaking apart. On the one hand, that’s not to say that the rapid decompression through the nozzle wouldn’t have been more than enough to do that as well. OTOH, I have no problem deferring to someone that’s not only been on the job for 25+ years and actually been out in the field, in burning houses, dealing with aftermath, talking to victims…victims that may have said ‘that extinguisher was only a few years old, I don’t know why nothing happened when I pulled the lever’.
Checking the first KIDDE manual I found, it doesn’t say anything about shaking or flipping it to break up the dry chemicals, but (and I was a bit surprised) that’s not because they tried to make it maintenance free. They ask that you check the pressure gauge, inspect it for dings and dents and check the hose or nozzle for debris monthly. So they could certainly add one more line that says ‘hold it upside down until you hear the powder falling’.
Oh, boy! ANOTHER thread I know something about.
Fire extinguisher manufacturers understand that their units will sit around unused for several years. (Keep in mind that ALL fire extinguishers have a requirement for periodic inspection and replacement or testing. The interval varies depending on whether they are rechargeable or non-rechargeable.) Most dry chemical extinguishers are charged (pressurized) with dry nitrogen. There is very little moisture in the cylinder, and the extinguishant should not be caking. It certainly doesn’t hurt to shake them or turn them upside down, but it is usually not necessary.
When I first started working in the industry I did fire extinguisher service. For annual servicing, we did turn them upside down and pound on them with a rubber mallet. This was many years ago and, I admit, I do not know what current service methods are.
At work we bring out fire extinguishers in annually for an inspection. I send my guy with them over to the place. They take them (3) and walk back out about 2 minutes later with a bill for $15. That’s still all they’re doing. Some places will clean all the dust off, hence the name ‘rag and tag’.
This is different that the 5 year hydrostatic test and it being replaced every 12 years.
I’m not entirely sure how much use there is in it, it seems that plenty of business, both large and small could do this in house, but for 5 dollars (plus or minus a few bucks) per bottle per year, I’m happy to get it shift the liability away from my business if something is wrong with it.
The requirement that rechargeable fire extinguishers be hydrostatically tested every six years actually figured into my resignation from a job a few years back.
I took over at a campus where the fire extinguishers had NOT been properly tested for at least 7-8 years. It is usually cheaper to just replace them all (as opposed to removing them, emptying and testing them, then refilling them). Total cost for the campus was about $10,000.
In a subsequent job review, it was pointed out to me that I had spent about $10,000 more than my predecessor for maintenance. I explained the reason, but my supervisor did not want to hear it. I then pointed out that they might as well budget another $10,000 for six years from now, or amortize the cost over the intervening six years. I was told that this couldn’t be done…no mechanism at all to handle it. I said, “So, if I quit right now, the person who gets my job will get credit next year for SAVING $10,000 when compared to what I have spent?” I was told he would.
I then pointed out that the same thing applies to emergency lighting (and FA system batteries). At periodic intervals, all the batteries in the emergency lighting units will have to be replaced. Would I get lower job ratings because I had to spend money every few years to do that (Code-required) maintenance work? Yes, if I exceeded the previous year’s expenditures.
You can see where this was going. I didn’t mind getting rated lower in my job performance as much as I couldn’t fathom the inability of the financial people to anticipate and budget for required, regular maintenance expenses.
End thread hijack…
I started to mention something about that but left it out. Currently, we bring out bottles to a place to have them rag and tagged each year, hydro tested every 5 years (6 years?) or to get new ones when they need to be replaced.
Before that there was a guy that came around once a year, he’d stop in, hold it upside down up to his ear, wipe it off, update the tag and ask for $3 (per bottle). It was great. We didn’t have to do a thing, he just showed up. We loved him, he did most of the small business in our city as well as some of the neighboring cities and seemed to be well liked by the fire department as well. In fact, we got word of him retiring by way of the fire department. They called to let us know that he wasn’t around and gave us the names of some other places to use.
Now, to get back to what you were saying. When it was time to get them hydro tested, he had some system of buying back ours (or maybe we just got rid of them, I’m not sure), and then we’d buy ‘used’ ones from him. I don’t know all the details, but somehow it worked out to be cheaper to replace ours when the hydro test came up than to get them tested.
I know the last time that test came up with the new place, I asked and they said they only sold new ones and the new ones were considerably more than just having them tested so that didn’t work out.
Now, on to my home. I just checked my personal ones. I’ve got two 3# bottles that are 12 years old that should probably be replaced and 7# bottle that’s less than a year old. I know that the small ones should be replaced, but I hate to get rid of them when they’re probably still fine. What I’ll end up doing is watching for them to go on sale and replace them, and keep these ones else where in the house as backups and maybe throw them out in a few more years.
Laws and inspection requirements do change so I may be wrong. But.
Last I knew a proper and legal inspection required a visual inspection of the valve inside the extinguisher. This required removing the valve from the top of the extinguisher inspecting the valve and most often replacing the disk.
The procedure was something like this.
The service man had a sealed with filtered vented box on his truck that he put the extinguisher in. The box had hand holes with rubber gloves on the side of the box. He would put the extinguisher in the box and turn it upside down, Blow off the N2 charge. Remove the extinguisher from the box. Remove valve from extinguisher and service the valve. Weigh the extinguisher and add any power if necessary. Put valve back on. Put proper amount of N2 in extinguisher. Reweigh. Wipe clean and put tag on extinguisher. But I did notice in the last years working that it became more of a weigh, rag, and tag operation.
What you explained, is the 6 (5?) year hydro test. You missed a few intermediate steps, including the pressure test, which is what makes it a hydrostatic test. The rag and tag operation is the annual inspection.
IIRC, the exception is that non-refillable ones can go 12 years without the hydro test. At that point I’m not sure if they’re tossed or if there’s a way to inspect them and put them back into service.
Also, there’s different frequencies for different types of units. Depending on what they’re filled with, if they’re portable or part of a permanent system (like you’d see over a commercial stove) etc. It can all get confusing. Luckily, in most (commercial) cases, you can look at the card on the bottle/pull handle and if it’s been less than a year, you’re good, if it’s been a year or more it’s time to call. Also, during your annual fire inspection they’ll point it out to you (but, of course, we’d rather stay in front of that).
What I explained was the yearly inspection. Rag and tag are just wiping down the extinguisher and putting on a new tag without inspecting or weighting.
No it is not permitted to hydro an non refillable extinguisher and for a business they are only legal for 1 year and are required to be replaced.
Sate of California.
Welp, having read this I just went around my place shaking them up. I keep a couple ABC’s and one just for electronics (if minor fire, I’ll be able to salvage something this way, instead of the sticky mess)
Don’t throw out/discard the old extinguishers. We had a yearly fire drill with demonstrations. Expiring extinguishers were practiced with. There was never a failure but the fire chief kept hoping so he could go, “Seeeee, that’s why we replace them on a regular basis.”
A couple of people had real life fires and mentioned that the yearly training and chance to practice reduced their stress level. “Damn, worked just like before!!”
I recall a thread on hear years ago about about someone saying their fire inspector (or maybe it was a friend that did inspections), kept the gauge from an old fire extinguisher in his pocket. When he made his rounds to the local businesses or did demos and explained to people the importance of replacing them from time to time and would inevitably here ‘but the gauge says it’s fine’, he’d pull the one out of his pocket and say ‘this one says it’s good too and it’s not even attache’, IOW, some times they break. I should see if I can find that. In fact, part of me wonders if flipping them over and shaking them could actually jam up the works, not knowing exactly how or where the powder is transported.
Well that was easy, it wasn’t someone’s inspector or even a FOAF, it was a still active doper that does fire extinguisher service.
http://boards.straightdope.com/sdmb/showpost.php?p=6464114&postcount=9
A couple of my clients have a hard and fast rule: An employee may not use a fire extinguisher until he/she has gone through the fire extinguisher training course. The course is only an hour long, but they use (expired) extinguishers to put out a small fire in a fire-pit. This uses up virtually all the expired fire extinguishers over a 5-6 year period.
If an employee who has not had the special training encounters a fire, the rule is “Get out, and activate a manual pull station as you leave!”
What about the liability reasons for forbidding employees to use them. Genuinely curious. I like the idea but wouldn’t that be a shitstorm to forbid anyone from using them, regardless of reason?
I was taught how to use one in grammar school (like we could actually get one off the wall let alone carry it). I took that ‘training’ and used a small one while on a skateboard as jet propulsion, it worked, at least.
Who do you go to to get them recharged with just the nitrogen? I have several that have lost their pressure but have never been used. I’d hate to toss them. but I’m having a hard time finding a place to service them.
If they’re the type that can be refilled just take them to a place that does fire extinguisher service. You can probably just walk in and ask. They may even do it while you wait if they have some time. However, you might find it cheaper to get rid of it (in whatever manner you choose) and buy a new one.
As for finding a place, there’s always the internet or phone book, but if you’re really struggling just look at the tags on the fire extinguishers you see in every store, restaurant, building etc that you’re in. They’ll all have the name of the place that does the service.
A lot of them will be places like Cintas or Aramark which isn’t what you’re looking for. Look for ones marked “[so and so] Fire Service” or “[something] Extinguisher”.
Cintas and Aramark and places like that are full services places that do everything from uniforms to carpet cleaning to alarm maintenance and a lot more.