Re: 2 wire vs 4 wire Smoke allarms

["Robert Green" <ROBERT_GREEN1963@xxxxxxxxx>]

Jeez,

I take a month's vacation only to find we're playing the same old games.
Lots of smoke and heat but very little light.  Ironic in a thread about
smoke detectors!  :-)

If anyone's *really* interested in resolving this question, it would be nice
if they would provide citations of some sort.  There's lots of info out
there.  Anyone with an interest in this topic would be well-served to read
the PDF articles here:

http://www.cpsc.gov/volstd/smokealarm/smokealarm.html

In fact, anyone who depends on wired, wireless or lithium powered smoke
alarms owes it to their loved ones to carefully read ALL the information at
that site.  This one alone:

http://www.cpsc.gov/volstd/smokealarm/UL22503in.pdf

about transients causing cascade failures in interconnected smokes is a
*must read* IMHO for anyone using interconnected smokes.

One of the things the materials on the CPSC site reminds readers is that
different jurisdictions have very different requirements and it's unlikely
there's a "one size fits all" answer to the question.  I *am* sure lots of
folks will benefit by reading the material about smokes at the CPSC site
(even though it's a little out of date) since there are so many house fires
each year:

"In 1999, there were an estimated 337,300 residential fires resulting in
2,390 civilian deaths. Smoke alarms have successfully prevented thousands of
residential fire deaths. Reducing the number of non-working alarms and
providing unprotected homes with smoke alarms may produce a further
reduction in fire deaths. CPSC staff believes that more effective alarms in
residential dwellings could have an even greater impact in reducing deaths."

(Below I've copied over just some of the articles to be found at the smoke
alarm home page: http://www.cpsc.gov/volstd/smokealarm/smokealarm.html

***************************************************
Proposals for 2008 Edition of the National Electrical Code - Comments due by
November 2, 2005.
http://www.cpsc.gov/volstd/NEC2008.pdf

Correspondence to Underwriters Laboratories
October 31, 2003. Response for comments on the Proposed
Requirements for the Fifth Edition of the Standard for Single and Multiple
Station Smoke Alarms, UL 217, Bulletin Dated October 1, 2003.
http://www.cpsc.gov/volstd/smokealarm/UL103103.pdf

Correspondence to Underwriters Laboratories
February 25, 2003. Recommendations to address potential reliability and
performance issues associated with interconnected smoke alarms, UL 217
http://www.cpsc.gov/volstd/smokealarm/UL22503in.pdf

CPSC Staff Report: Considerations for Installation of Smoke Alarms on
Residential Branch Circuits - (October, 2005)
http://www.cpsc.gov/library/foia/foia06/os/acfismoke.pdf

CPSC Staff Report: Possible Technologies for Improving the Audibility of
Residential Smoke Alarms for Older Adults - (September, 2005)
http://www.cpsc.gov/library/foia/foia06/os/audibility.pdf

Contractor Report on The Audibility of Smoke Alarms in Residential Homes -
(September, 2005)
http://www.cpsc.gov/library/foia/foia05/os/audibility.pdf

A Review of the Sound Effectiveness of Residential Smoke Alarms - (December,
2004)
http://www.cpsc.gov/library/foia/foia05/os/alarm1.pdf

Contractor Report on The Implementation and Demonstration of Wireless
Communications Capabilities in Off-the-Shelf, Battery-Powered Smoke Alarms
Phase II Report - (March 23, 2004)
http://www.cpsc.gov/LIBRARY/FOIA/FOIA04/os/offshelf.pdf

Contractor Report on Smoke Alarms, Low-Cost Batteries, and Wireless
Technology Technical Report: Phase I - Preparatory Study and Literature
Search - (August 29, 2003)
http://www.cpsc.gov/LIBRARY/FOIA/FOIA03/os/Lowsmoke.pdf

Final Report on Lithium Batteries (UltraLife, ANSI 1604) Used in Residential
Smoke Alarms - December 2, 2002
http://www.cpsc.gov/LIBRARY/FOIA/FOIA03/os/Smokalrm.pdf

NIST Report on Home Smoke Alarm Tests
http://smokealarm.nist.gov/

Consumer Product Safety Review: Winter 2004
http://www.cpsc.gov/CPSCPUB/PUBS/cpsr_nws31.pdf

***************************************************

Happy reading!  (Only 419 unread messages left in CHA.  Jeez, I hope they're
not all about how make interconnected smoke alarms can dance on the head of
a pin!)  :-)

No, wait, I see plenty of other threads.  Phew!  Sorry if I left anyone
hanging with unanswered messages.  I will try to get to them shortly.  My
wife insists I no longer announce my vacation plans over the internet ever
since someone tried kicking in the alarm door when we were away.  It's
really a buzz kill to have that message waiting at the hotel's front desk.

--
Bobby G.