3 ms·

Underwriters Labs make you pay to see that. I can show you the table of contents, though: http://ulstandardsinfonet.ul.com/tocs/tocs.asp?doc=s&fn=0217.toc http

• eli 12y ago
  But... every smoke detector I've bought in the last decade has had silence button. So how it is against any regulation? According to a quick google, all smoke detectors in Maryland are required to have a hush function by 2018. So... pretty sure that isn't prohibited by regulation there. FEMA says the best smoke detectors have a temporary silence button. I guess maybe there are some states that prohibit it? Seems awfully foolish though: temporary hush buttons save lives.
  • raldi 12y ago
    If the device detects a sufficiently-high level of smoke, the button is ignored.
    • CamperBob2 12y ago
      Again with this statement, accompanied by absolutely no citation.
      • raldi 12y ago
        I posted a link to the citation in the root comment of this thread.
        • CamperBob2 12y ago
          Sorry; I meant a citation to the actual law people are referring to, the one that says smoke detectors shall not be capable of being manually silenced in the presence of smoke. Smoke detector user manuals might vaguely allude to such a law to justify crappy engineering, but that's not the same as a citation to specific Federal, state, or municipal codes, or even an insurance underwriting code.
          • raldi 12y ago
            The actual law is "Do what UL says". Or, to use a direct quote: "The U.S. model codes and installation standards require smoke alarms and smoke detectors to be listed in accordance with the Standard for Single- and Multiple-Station Smoke Alarms, UL 217, and the Standard for Smoke Detectors for Fire Alarm Signaling Systems, UL 268." http://osfm.fire.ca.gov/firelifesafety/pdf/Smoke%20Alarm%20Task%20Force/CSFM%20SATF%20Report%208-16-11.pdf http://osfm.fire.ca.gov/firelifesafety/pdf/Smoke%20Alarm%20T...
            • CamperBob2 12y ago
              I'm missing the part that justifies what we see in that video. He's unable to mute the detectors, but there seems to be a distinct lack of smoke. Why are people carrying water for this idiocy? Nothing in the document you linked has anything to do with the subject at hand. Fine, whatever, you're not supposed to be able to mute the detector in the presence of heavy smoke. But there is absolutely no prohibition against a mute feature in general.
              • raldi 12y ago
                I found a citation that I think even you will accept: https://community.nest.com/message/36003 https://community.nest.com/message/36003
                • CamperBob2 12y ago
                  True, and the 4% business was also mentioned in the summary document earlier. That doesn't change my two underlying points: (1) it's an incredibly stupid regulation that seems to have been designed to cause people to remove the battery or otherwise disable their smoke detectors permanently to avoid nuisance alarms; and (2) there was no smoke at any level in this scenario. Poor engineering on Nest's part led to a situation where a poorly-thought-out regulation came into play. Neither condition is defensible... yet look at all of the people in this thread trying to defend one or both. (Yes, I'm moving the goalposts to a certain extent, as I was mistaken about there being no law against silencing a smoke detector in the general case.)
        • eli 12y ago
          Since I can't actually see the document, does it say that the fire alarm can't be muted even in heavy smoke? Or are you just guessing that it might? I would find that surprising.
          • raldi 12y ago
            I don't know. UL doesn't make their rules openly-available. You have to pay them to read them. But Nest's website says UL's rules forbid the silencing, and I see no reason to think Nest would lie about it.
          • raldi 12y ago
            I found the relevant citation: https://news.ycombinator.com/item?id=9064731 https://news.ycombinator.com/item?id=9064731
      • jellicle 12y ago
        I recently purchased a non-Nest smoke alarm. The documentation explained that if there was an alarm, the hush button would silence it temporarily, but if there was a high level of smoke, the hush button would not work and the alarm would not be able to be silenced. Since both Nest and other smoke alarm companies say this, I conclude there is some regulation to this effect. The Nest device in the video did not appear to be experiencing high levels of smoke.
        • raldi 12y ago
          Found a citation: https://news.ycombinator.com/item?id=9064731 https://news.ycombinator.com/item?id=9064731
    • icelancer 12y ago
      Yes, this is infuriating. It happens on my networked system of smoke alarms. It ignores the hush for nearly a minute while the smoke clears out. Ridiculous. Makes me want to just disconnect all of them.
• CamperBob2 12y ago
  UL is not a lawmaking body, so if they have regulations against being able to hush a smoke detector -- and I highly doubt that -- Nest is technically under no obligation to obey them.
  • jsprogrammer 12y ago
    In effect, they are. Many regulations reference their standards, require devices meet a specific UL standard, or recommend that devices be stamped with a UL approval.
  • UnoriginalGuy 12y ago
    Here's the gotcha though... A smoke detector company sells a safety product, if that safety product fails they could easily be sued for the lifetime earnings of a dead individual (or even family in some cases). So that requires that these companies have insurance, and in order for insurance to cover them they must meet certain insurance dictated requirements, which can be anything, but UL specifications are an easy thing to point at (to both protect the company from liability and insurance from payouts). So while in some locations there might be no government regs, insurance is making regulations all on their own, and these companies can either play along OR risk paying out up to millions of they get sued.