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B Most accurate smoke detector

  1. May 21, 2017 #1
    What are the most accurate smoke detectors have you come across and can recommend and why? Are there different types of detectors (I want to avoid the radioactive ones but are others less accurate)?
     
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  3. May 21, 2017 #2

    berkeman

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    Do you just mean in-home smoke detetors for fire protection?

    https://en.wikipedia.org/wiki/Smoke_detector

    What have you found so far in your reading? Can you post some links to your reading?
     
  4. May 22, 2017 #3
    I read the above and other basic reference.. it says the Einstein Photoelectric smoke detector is more accurate during start of fire and the Curie Ionization smoke detector is more accurate during strong fire.. but for them to work, the smokes have to be high in the ceiling.. I was asking for personal experience for either of them... and are there no new ones based on new technology like lasers that can detect even a burning paper on a table before it reaches the ceiling.. I need something very sensitive.. thank you...
     
  5. May 22, 2017 #4

    berkeman

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    Can you say more about the application? You might be able to add a PIR sensor to a standard smoke detector to give you early small flame detection. Are you familiar with Passive IR sensors?
     
  6. May 22, 2017 #5
    Yes I have passive IR sensors for motion detection.. can they really detect smoke? But I need a backup smoke detector at home that can detect when a paper is initially burning and not when the smoke/fire is so much that it's not possible to put out.. my purpose of smoke detector is not to run after smoke or fire but put them out while they are still of low intensity...
     
  7. May 22, 2017 #6

    berkeman

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    PIR is no help with smoke, but can detect growing hotspots and flickering flames. But other moving IR sources also generate PIR activity, so it would be limited to an empty room for growing flame detection.
     
  8. May 22, 2017 #7

    berkeman

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    BTW, putting out a fire is non-trivial. Especially if the source is electrical. How do you plan to put any small fires in your home out? And do you anticipate some sort of fire problem at your home? Are you overloading the electrical circuits?
     
  9. May 22, 2017 #8
    Fire extinguishers can put out small fires.. but if the smoke detector would be so sensitive.. the fire would still be small enough to be extinguished by fire extinguishers.. I lease the house to other people and they have lots of papers.. and I'm responsible for putting fire detectors and other safety device.. I just want update in case there is a latest gadget that is so sensitive compared to the ionization and photoelectric based..
     
  10. May 22, 2017 #9

    berkeman

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    Fair enough. Per the Fire Triangle, you need an ignition source, or the papers are benign. Do you have a no smoking policy for your tenants? Do you have CO detectors in the property (slightly off-topic for your fire question, but important if you are trying to keep everybody safe)?
     
  11. May 22, 2017 #10
    I have CO detectors in my own house.. but I can put there if it's required. My worry is arson... because many times at night.. they slept over in friends house so the house is empty.. what if someone throws a rock at the window and then throw a flame through the broken window. I need fire detector that can immediately detect any small smoke so I can drive to the house about 10 minutes drive and put out the fire. You may say to put glass break detector.. yeah.. but I'm asking about the fire detector angle..
     
  12. May 22, 2017 #11

    berkeman

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    Is monitored home security available in your area? Near me, AT&T and Bay Alarm both offer monitored home security which includes fire protection.

    If a fire starts there and you are 10 minutes away, you probably will not be able to do much with a fire extinguisher. Small fires with normal combustibles in homes double in size about every 30 seconds, so 10 minutes is.... Well you can do the math.

    On a side note, I was able to knock down a neighbor's house fire with a 10-pound fire extinguisher a few years back (and save the house) because I happened to be at home on a weekend and heard the (regular) smoke alarm going off a few houses down the street. It turned out to be a bed fire (do you know how to put those out with an extinguisher?) that was started by a child playing with matches while the parents were asleep in a different room. I have extra fire extinguisher and fire safety training from our local Fire Department, though, so you should never try to put out a small house fire on your own without getting lots of special training and practice.

    Please be safe!
     
  13. May 22, 2017 #12
    All my fire extinguishers are 10-pound.. to put out a bed fire.. you spray them of course.. why what techniques do you use to put out a bed fire?
     
  14. May 22, 2017 #13

    berkeman

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    No. That will not work.

    Please check with your local Fire Department to ask about citizen training to help you judge what size fires you can fight, and how to correctly use a fire extinguisher. Staying safe (walking away and calling 911) when the fire is too big, and effectively using a fire extinguisher when the fire is small enough are important skills. Hollywood has done a serious disservice in their representation of citizens fighting fires with extinguishers, IMO.

    You can also check the FEMA link in my footer to see some of the training we use in the US for Citizen Corps groups, like CERT Teams.
     
  15. May 23, 2017 #14
    Our fire department doesn't have spare fire extinguishers and they only use fire truck and the Fema website doesn't have details how to use fire extinguishers. I've been googling about "how to use fire extinguishers on bed" and the closest I can find is:



    You mean it should be used side to side on bed? PASS = Pull at Pin, Aiming at Base, Squeezing and Side and side movement? Well.. maybe there will be training months from now but in meantime with my 7 fire extinguishers at least just share how to put out flame on bed to have some idea meanwhile. Thank you.
     
  16. May 23, 2017 #15

    hilbert2

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    Some smoke detectors can give false alarms from excessive water vapor, like in a small apartment after someone's taken a shower. Then it's not good if the device is too sensitive. In some situation smoke detection is not a good way to detect fires, but that's mainly a problem in very large volume spaces (industrial halls, etc.) where it would take too long for the smoke concentration to reach detection limits.
     
  17. May 23, 2017 #16

    berkeman

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    That's a fake bed fire (staged by the Fire Department for the sake of the video using natural gas). A bed fire that big already is marginal for a 10 pound extinguisher, and way too big for the little extinguishers they show in the video. The one that I put out was about half that size when I got to it. The best advice in the video comes at the end when they say "know when a fire is too big to fight with an extinguisher, and get out". Did you see the smoke at the end? For a real fire, that smoke is toxic, and can cause you to pass out and die pretty quickly.

    The main trick for a bed fire or a car fire is to shoot the extinguisher underneath the bed or car, and let the heat draw the chemical up into and through the fire. Did you see in the video how shooting down at the bed fire with the extinguisher just got the stream deflected upward by the heat and flames?
     
  18. May 23, 2017 #17
    How can the heat draw the chemical up into and through the fire.. you mean by equilibrium? like the fire extinguisher fuel is like ice and it can spread the coldness into the fire? but how much does this equilibrium conduction occur?

    Also about the smoke detector.. it will be connected to an alarm unit which can call me in the cellphone in the event of a trigger. Can the smoke detector be put in the wall so is nearer to the smoke (and faster trigger) if the room is not so big?

    Don't worry. I'd ready dial the fire department and let them handle the job.. but just need some basic. Thank you.
     
  19. May 23, 2017 #18

    berkeman

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    Please think about the airflow around a fire. The fire heats the air around it, and hot air rises. So in a fire, the airflow is strongly upward through the fire. That's why you use that airflow to fight the fire.
    Yes, be ready to call the closest fire department dispatch center directly (do you know you have the best phone number for that?), and give them the exact address.
    You're welcome. Please be safe. Please take any trainings you can, and always use the "Sizeup" techniques that you are taught in those trainings.
     
  20. May 23, 2017 #19

    berkeman

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    Sorry, I need to close this thread. Anybody who would like more fire extinguisher training, please contact your local fire department or CERT team. If you are having trouble finding that training, please send me a PM.. Thank you.
     
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