In message <[email protected]>, dated Wed, 27 Jul 2011, Brian Oconnell <[email protected]> writes:
>S1851, NFPA10, etc establish maintenance intervals for portable fire >extinguishers as (typically) one year. While some standards specify an >annual hydrostatic test, gage verify, etc; none discuss the physical >basis of this requirement. > >Why not 9 months or 34 months? Is there any performance or reliability >data for portable fire extinguishers that indicates 12 months provides >an n-sigma margin or whatever? I suspect that 1 year has simply been found to work. Only a very few failures but not none at all, ever, which would indicate that a longer interval would be OK. I also wonder if some 'failures' are due to extinguishers growing little legs during the year, and running away. -- OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK When I point to a star, please look at the star, not my finger. The star will be more interesting. - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to <[email protected]> All emc-pstc postings are archived and searchable on the web at: http://product-compliance.oc.ieee.org/ Graphics (in well-used formats), large files, etc. can be posted to that URL. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <[email protected]> Mike Cantwell <[email protected]> For policy questions, send mail to: Jim Bacher: <[email protected]> David Heald: <[email protected]>
