Talk:Smoke detector

General Problems with Article

The article hardly cites any sources and reads like smoke-detector propaganda, prescribing use, suggesting positioning, asserting that batteries need be replaced semi-anually, etc. Additionally, the article is very North-America-centric, discussing NIST, UL, NFPA, "building codes" (which are presumably in the States?). Perhaps it could be rewritten / modified to have a broader, more neutral perspective. —Preceding unsigned comment added by 98.223.202.213 (talk) 03:05, 14 March 2008 (UTC)

History

Anybody know any history? When was it invented, where, by who? Edward 10:45, 3 Jun 2004 (UTC)

Quote-The first battery-operated home smoke detector was patented in 1969 by Randolph Smith and Kenneth House.

What is the source of that quote?--AI 02:55, 16 Jun 2005 (UTC)

This http://inventors.about.com/library/inventors/blfiresprinkler.htm is the source of the quote.

WHAT IS THE SOURCE FOR THE ANDREW DARBY ARTICLE?

In case anyone is curious, most of this history is almost entirely FALSE. The first electric fire alarm was invented in 1890 by Francis R. Upton and Fernando J. Dibble, (US patent no. 436,961). And while Duane D. Pearsall may have invented A home fire alarm, there are records of similar home fire alarms ten years earlier. PLEASE let's fact check, people. —Preceding unsigned comment added by Deltadromeus (talk • contribs) 16:15, 6 February 2008 (UTC)

I need to know more info on George Andrew Darby

I need a book,encyclipedia,etc. on George Darby

how is the anecdote 'unconfirmable' if his device was patented?131.111.200.200 (talk) 00:49, 26 August 2008 (UTC)

Photoelectric detectors

• Note: There has been some recent research that has proven that "Photo-Electric" smoke alarms do a much better job at detecting smaller fires, whereas the Ioniasation detectors could only detect a small fire (which could in turn, could burn rapidly out of control) after a minimum of ten minutes! The photo-electric alarms however detected the fires almost a fast as they detected a large fire. This issue is still under investigation and research but the word is spreading and a few government (Australian, I'm not sure about others) organizations have admitted that these new alarms do work a lot better. - Random Australian Guy (Sydney)

Reliability

The two paragraphs under the reliability section are conflicting:

In the 1990s Texas A&M University did a full scale scientific investigation... The study determined that in a smoldering fire, with its relatively low number of large smoke particles, optical detectors fail 4.06% of the time, while ionization detectors fail 55.8%. For flame ignition fires, which have a large number of small, energetic smoke particles, photoelectric smoke detectors had a 3.99% probability of failure while ionization smoke detector failed 19.8%.

In 2004, NIST issued a comprehensive report... The report concludes, among other things, that "consistent with prior findings, ionization type alarms provided somewhat better response to flaming fires than photoelectric alarms, and photoelectric alarms provided (often) considerably faster response to smoldering fires than ionization type alarms".

The A&M study is likely interpreted or transcribed incorrectly and should be removed until clarified

Reasoning:

As a class, flaming fires produce larger numbers of invisible (.1 to .01 micron) particles of combustion than slow smoldering fires, (owing to the process of agglomeration of smaller smoke particles as they cool).

Photelectric detectors are by definition unable to detect invisible particulates (particulates so small they do not reflect a particular wavelength of light, e.g. less than 20% of the wavelength) Ionization detectors are readily influenced by these invisible particulates. Detectors operating on the ionization principle detect particles of combustion as they collide and combine with ionized air molecules, causing the ionized air to lose thier mobility . Each smoke particle thus becomes a collector of ions, and the number of ionized particles in the chamber once reduced, naturally reduces current flow proportionately. This reduction in current triggers the electronic circuitry and is interpreted as a smoke signature.

Simple observation will verify that the smoke particulates are most visible (larger) further from the fire.

a quick check of the Texas A&M Engineering web site supports this conclusion

Also reference the 18th edition of the Fire Protection Engineering Handbook for supporting documentation, and The NEMA Guide for Proper Use of Smoke Detectors Axcadd 04:09, 24 June 2007 (UTC) Axcadd 04:43, 26 June 2007 (UTC)

Smoke Detector vs Smoke Alarm

The introduction paragraph makes a statement that may need a rewrite of the article and its structure;

A smoke detector or smoke alarm is an active fire protection device, subject to stringent bounding, that detects airborne smoke and issues an audible alarm, thereby alerting nearby people to the danger of fire.

What I mean by this is that there is a difference between a Smoke Alarm comprising a sensor and audible warning device and a Smoke Detector that forms part of a network of sensors connected to an alarm panel.

Perhaps the article could be written with s summary of the technology of smoke detection (ionisation vs optical) and then the application of these technologies, being in the form of smoke alarms and smoke detectors.

Volume

I "heard" that in Canada tests have caused the volume of the smoke detector alarms to be increased beyond the pain threshold level. This was apparently driven by the discovered that many people, particularly children, had no trouble sleeping through a normal smoke detector even when it was positioned directly above their bed. A quick look around, and I couldn't find a cite.

Personal experience tells me this is true, though. My parents moved from their temporary apartment that was less than a year old into a newly constructed house. The detectors in both these locations are so loud as to be very painful, even for a few seconds while you push the "silent for 20 minutes" button (i.e. after burning the toast). Fracture^Talk   06:11, 2 September 2006 (UTC)

There's a ton of research on the volume of alarms. Recent studies gaining attention have tested the effectiveness of waking children with alarms of different volumes and in combination with voice recordings (parent's voices) Here's one such study from Australia's Victoria University: THE EFFECTIVENESS OF DIFFERENT ALARMS IN WAKING SLEEPING CHILDREN It supports your claim children are generally more difficult to awaken.MikeDayoub 22:07, 8 November 2006 (UTC)

I can believe it, too. I put some chips in the oven last year while drunk, fell asleep, and only woke up when every alarm in the house was going. The pain in my ears from the things was incredible. Very ow. And this little drunken baby would almost certainly have slept through an alarm only as loud as, say, my alarm clock.Unreadablecharacters 15:50, 29 November 2006 (UTC)

Disposal

What about discarding an old smoke alarm? Should a smoke detector be treated as special waste because of the radioactive source? Do people putting smoke detectors in the trash cause an environmental problem? I only found little about it here: [[1]] --Sasper 23:20, 15 December 2006 (UTC)

Replacement: Every 10 Years

http://money.aol.com/smoney/general/replacing-common-household-items —The preceding unsigned comment was added by 70.126.236.103 (talk) 07:20, 19 February 2007 (UTC).

Testing Section

I am not happy with the phrase "virtually all" because it is also uncited, but I feel that it is better than the previous wording. The problem here is that each state in the US has it's own codes for smoke detectors, and the NFPA doesn't require a test button that I can find anywhere. I have never seen a detector without one, and I talked to several friends (a couple internationals) and they concurred. I do not think it is universally required, but I think it is fairly universal. Thoughts? Zab 15:35, 7 April 2007 (UTC)

Also, this sentence: "Many people simply wave a lit match underneath the detector to test it; this is dangerous, however, as it can set the smoke alarm and the rest of the house on fire. A better way is to blow cigarette smoke into the detector." is one of the stupidest things I've ever seen. First of all, a lit cigarette waved under the detector is as dangerous, if not moreso than a lit match, partially because over several tests, the unfiltered tar can collect on the sensors and impair their function. Second, a lit match waved under a detector is not going to burn long enough to melt and ignite the plastic in a detector - even if held in one place. A better test than cigarette smoke would be: Light a match, blow it out, THEN wave it under the smoke detector. The match test is reliable, convenient, costs nothing, and I'd imagine is the preferred test for the majority of people who are nonsmokers and don't really want to buy or burn tobacco products in their homes for the sole purpose of testing their smoke detectors. 97.82.247.200 17:44, 5 July 2007 (UTC)

Cigarette detector

I have removed this section. This section does not belong in this article, as it refers to optical flame detectors. However, there presently is not a flame detector article. Additionally, the specific application cited in this section - detection of smoking in schools - is not used as a portion of a fire alarm system, but rather is a method of aiding rule enforcement in schools. As this system and components have not been listed by a third party testing laboratory for use in fire alarm systems as required by model building codes, it cannot be used for that purpose. Therefore, it does not really belong in any article pertaining to fire alarm systems. Fireproeng 03:24, 23 July 2007 (UTC)

why is there a commercial website selling smoke detector products on this page???

Range of detectors from smoke to ultra violet - http://www.discountfiresupplies.co.uk/category/72/Fire-Alarm-Detectors

This link is actually a sales link with very limited useful information - please remove —Preceding unsigned comment added by 130.219.8.253 (talk) 20:25, 25 October 2007 (UTC)

Typical Quantity of Americium-241 in a Household Detector

The article says this is 0.2 microgram, meaning one gram of Am-241 could make about 5 million detectors. According to my physics text book and http://www.uic.com.au/nip35.htm, one gram would make only 5000 detectors, meaning each contains about 0.2 milligrams. It matters little whether the material is oxide or pure metal, as each Am atom weighs many times more than an oxygen atom. I'll change the page now, but would welcome more info. StuFifeScotland (talk) 15:06, 27 January 2008 (UTC)

The wiki article on americium states "(about 0.2 microgram)" which seems more reasonable.Skipweasel (talk) 22:04, 4 February 2008 (UTC)

VESDA Merger Proposal

Rather than outright deleting the VESDA article, I believe it would be worthwhile to merge the content into the Smoke detector article, as it is another form of smoke detection that is not already covered in this article. While it may not meet notability on its own grounds, it may do so as a member of the smoke detector article/family. --206.53.253.150 (talk) 19:11, 2 April 2008 (UTC)

CO2 - a better indicator?

hi! should we mention that CO2 level can help to distinguish between dangerous smoke and "harmless" cig smoke or smoke from a pan or steam from a pot...? [2] i have heard that in kitchens IR detectors r the fire detectors of choice... bye --Homer Landskirty (talk) 13:57, 8 September 2008 (UTC)

i just did it... :-) --Homer Landskirty (talk) 09:03, 11 September 2008 (UTC)

Americanium nuclear bomb

because the americanium in smoke detectors is fissile it could be use to make an A-bomb. I just did the math and according to this it would that over 62 million smoke detectors to make said atom bomb.