This weekend had boat owner tell me they had been told by an examiner that fire extinguisher must be mounted vertically (on the side) to keep the powder from caking up. Understand that mounting, while no longer required is a good idea. Question is about on their side? Anybody here this policy or just is this just misinformation.
I will not address policy, however, it is true the vibration, vehicle, boat, etc. will cause the dry power in a fire extinguisher to settle and cake in place. During annual inspection of commercial fire extinguishers, what the inspectors term “tap and tag” the fire extinguisher is turned up side down and a rubber mallet is used to tap on the body to loosen up the power. As a general practice it is probably a good idea to do this on a regular basis or at minimum turn the extinguisher in the opposite orientation it has been stored and hit it against something prior to trying to use it, however, remembering to do that when it is needed, well you get the point.
Although even the VE manual uses the term 'caking', the problem you are trying to prevent is 'packing'. At the bottom of the page is the section "Common Misconceptions".
While a vertical mount can lead to packing,
quote:
it is extremely unlikely that the dry chemical in a properly designed cartridge unit can become so packed that the gas distribution system cannot overcome the packing resulting in an incomplete discharge of the dry chemical.
My guess is that the info in the VE Manual is based on old and out-of-date advice or it always was an old wife's tale. I worked on the last revision of the VE Manual and I know we didn't go back in and re-verify that sort of advice. We just assumed it was correct. We were much more interested in getting the rules & regs info updated and correct.
With that said it couldn't hurt to dismount the fire extinguisher from time-to-time and give it a good inspection and a tap or two. If you are depending on it to save your life, don't you think it should be looked at more then once a year? (generic question - not aimed at the poster).
Originally posted by bbeckerusa: This weekend had boat owner tell me they had been told by an examiner that fire extinguisher must be mounted vertically (on the side) to keep the powder from caking up. Understand that mounting, while no longer required is a good idea. Question is about on their side? Anybody here this policy or just is this just misinformation.
so wouldn't that result in the powder caking up Vertically instead of horizontally? Why focus on alignment of the mounting instead of the rubber mallet and uncaking process?
it is extremely unlikely that the dry chemical in a properly designed cartridge unit can become so packed that the gas distribution system cannot overcome the packing resulting in an incomplete discharge of the dry chemical.
If the typical mariner had a Cartridge Unit. But typical exstinguishers are stored pressure and the Ansul Bulletin 45
quote:
So, it is entirely possible to have packing occur in a stored pressure extinguisher.
quote:
- High quality extinguishers, of both cartridge-operated and stored pressure types, are designed to overcome packed dry chemical conditions. - The best assurance against extinguisher failure due to either condition is to use quality equipment and to follow the manufacturer's recharge and maintenance instructions closely.
It appears that Ansul agrees that a Horizontal Mount would be less likely to undergo packing. And that probably for at least the Standard Quality if not all Ansul extinguishers charged at the factory or perhaps properly qualified external sites. That this will not become a problem.
So what about the Kidde Mariner? Which is the most common I find followed closely by other models from Kidde. Was the particular unit on the boat charged at the factory?
When is a problem not a problem? If you shake a dry chemical F.E. up and down (i.e.,along its long axis, top to bottom) you should be able to feel the filler moving inside the same way you would feel a liquid were the container partially empty. If it doesn't shift around it's compacted or caked. Usually a few good shots with the heel of the hand loosens the filler up. If you've ever disassembled a dry powder F.E. you would be aware that the tube which conducts the powder extends to the bottom (end without the valve mechanism). In this configuration you have the best chance of the extinguisher working no matter the condition. I am guilty of telling the owners of cheap extinguishers, those without gauges and non-refillable, to save their pennies to get real equipment. Storage position really doesn't matter although placement does.