CO detectors... Are "chemical", and despite a feeling of security when you hit the self-test and it goes BEEP, that's only an electrical test NOT A FUNCTIONAL test. You can buy CO test kits, a gas with CO in it, or use other sources of CO to make sure it really works.
SAME applies to photoelectric or Ionization smoke detectors. The real failure of government is the CPSC, who consistently fails to monitor long term quality, and relies on UL and other testing labs. How else would you explain the air bag recall 60+ million and growing. Harvey Parad ________________________________ From: Hardwarehacking <[email protected]> on behalf of [email protected] <[email protected]> Sent: Saturday, April 15, 2017 12:00 PM To: [email protected] Subject: Hardwarehacking Digest, Vol 71, Issue 7 Send Hardwarehacking mailing list submissions to [email protected] To subscribe or unsubscribe via the World Wide Web, visit http://lists.blu.org/mailman/listinfo/hardwarehacking Hardwarehacking -- Hardware Hacking List - BLU<http://lists.blu.org/mailman/listinfo/hardwarehacking> lists.blu.org A Boston Linux/UNIX sub-group for discussion of open source hardware, embedded Linux, the DIY movement, and hardware hacking in general. To see the collection of ... or, via email, send a message with subject or body 'help' to [email protected] You can reach the person managing the list at [email protected] When replying, please edit your Subject line so it is more specific than "Re: Contents of Hardwarehacking digest..." Today's Topics: 1. Re: Spam (7.632):Re: Smoke detectors self-destruct (Ethan Schwartz) ---------------------------------------------------------------------- Message: 1 Date: Fri, 14 Apr 2017 14:40:22 -0400 From: Ethan Schwartz <[email protected]> To: [email protected] Subject: Re: [HH] Spam (7.632):Re: Smoke detectors self-destruct Message-ID: <[email protected]> Content-Type: text/plain; charset=utf-8; format=flowed On 4/14/17 11:20 AM, Federico Lucifredi wrote > On the business level, I do not agree: these detectors cost $25-50 because > they have a government-guaranteed demand curve, and vendors are just waiting > for the money to come in. While the government clearly has good reasons here, > the combination of that with limited competition gives you? pricey sensors. I > could be paying $50 for all sort of parts of my house that come for $4.50 > today? like my basement flood sensor, which folks have to sell to me without > a government mandated demand. I hope we get there soon for these as well, I > see no reason for something produced in the tens of millions to be this > pricey ? It is not an iPhone! You're making the argument that despite steady high volume demand there is limited competition in the market and that the limited competition has resulted in pricey devices which implies they are making large profits (your comparison to iPhone) at your expense. I would argue that if there is profit and steady demand in the market then someone else will come along and make a device and sell it slightly cheaper. However, if the cost of starting up a detector-making business isn't worth it (hence why there is limited competition) then it stands to reason there isn't actually as much profit as you might believe in these devices. I also do not think that volume necessarily translates to lower prices. A CO sensor is more complex than a flood sensor--a flood sensor is generally just resistance measurement between two bits of metal and the resistance drops when water/moisture fills the space between them--so the pricing may be vastly different on these sorts of devices even before you consider that there is another sensor in there for detecting smoke, which may be ionizing, photoelectric or both... If we wanted to compare the current combination CO/Smoke detector market to cell phone market, it would probably go something like this-- The $10-15 no-brand combination detectors you can find on the shelves are the ZTE or unknown Chinese-brand names. Brand names change every few years, and those that survive are synonymous with build-grade cheapness. These are the absolute lowest cost and minimum viable product designs to meet standards. They may use older technologies that are still working but less than ideal when it comes to lifespan or reliability. The $25-50 Kidde/First Alert detectors are HTC and Samsung, they have a wide range of model options from inexpensive to expensive with various features and other improvements coming along with the highest priced models, but the key is that the brand is established and trusted. Then $100 Nest Smoke/CO detector would of course be Apple and their iPhone ;-) ... They are essentially premium price and feature set, many would argue a vanity product based on feature set alone. I must admit that I know very little about what goes into the COGS for a combination CO/smoke detector, so you may very well be correct that there is 300-1000% markup between manufacturer cost to build and the retail price on an average detector--but I have worked in the commodity device manufacturing world and I just don't see those kinds of margins going unchecked long term. HOWEVER, all of that said... at the end of the day we've really only got 2 manufacturers on the market: First Alert/BRK and Kidde/Knighthawk... So either I'm right and these guys are splitting the market share between themselves on what is a high volume, but low margin, product... or you're on to something and it's all collusion ;-) >> If you have gas appliances in your basement I'd have an explosive gas alarm >> down there too. > Now this is actually interesting. I have all of the above already but not the > explosive gas alarm (I am a sensor guy, I get these even when I don?t need > them to learn more about them), do you have a model you use/recommend? > > Thanks for sharing! I can't recall the manufacturer, but it was either Kidde or First Alert, which if you note my last comment above stands to reason, since there really aren't other options! IIRC it ran off of AC power with a 9V backup battery, and it also had a ~7 year kill-clock based on the sensor gradually losing sensitivity over time. I can't recall the price, but was under $50. ------------------------------ Subject: Digest Footer _______________________________________________ Hardwarehacking mailing list [email protected] http://lists.blu.org/mailman/listinfo/hardwarehacking Hardwarehacking -- Hardware Hacking List - BLU<http://lists.blu.org/mailman/listinfo/hardwarehacking> lists.blu.org A Boston Linux/UNIX sub-group for discussion of open source hardware, embedded Linux, the DIY movement, and hardware hacking in general. To see the collection of ... ------------------------------ End of Hardwarehacking Digest, Vol 71, Issue 7 **********************************************
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