Smoke Detector types and mounting location best practices

[Dsanduril]

For those outside the US we use the EI Electronics EI650 series. There are a lot of options so you can mix and match. We use the 10 year sealed battery versions with wireless network. We have a total of 7 on the boat: 1 in each engine room (2), 1 in each sleeping area (4), and 1 in the galley. Some of them are CO/smoke (galley where we have both cooking and diesel heater outlet), others are just smoke. There's about a 3-second delay over the network, so if you get to the galley (we set that one off somewhat regularly) silencer quickly you can prevent the boat-wide alert, but otherwise there are 7 85-dB alarms going off. Enough to wake even the most tired (but not the deaf, and we do not have the lighted versions).

When the watermaker sprung a leak on the high pressure side and was spraying atomized hot sea water it was the smoke detector that alerted us

[Cadence]

I wouldn't worry about "marine". Get the ones for residential use. They beep if the 9V battery goes down, put in new batteries annually. I would not worry about hearing one unless it is a long distance away. Being proactive is great, may I suggest an extinguisher close to each alarm. It's nice knowing your on fire but good being able to put it out.

[GordMay]

Originally Posted by sailorboy1

= incorrect Carbon monoxide is not heavier than air - in fact it is slightly lighter as CO has the RMM of 28 whereas air is slightly more than this. It is therefore almost neutral density. However in a normal room, thermal convection current dominate transport of gases in a room.

Yes, carbon monoxide is slightly lighter than air*, and rapidly diffuses evenly throughout the room. Studies have shown no significant difference in measurements based on what height CO detectors are mounted. Different manufacturers recommend different mounting locations, and you should always follow the manufacturers’ recommendation.

*CO has a molar mass of 28.0, and air has an average molar mass of 28.8.

[fragglerock]

Propane is heavier than air and so will pool in bilges perhaps that is what is being half remembered

Worth having a detector for that too!

[wrwakefield]

Chris,

We installed the battery powered version of Nest Protect combination Smoke and CO alarms in our 43ft monohull [6- AA Lithium batts last 2+ years for us...] They network wirelessly using the boat's WiFi and each act as an announcer [spoken word] when one sounds an alarm.

I like it when the unit in our sleeping cabin anounces 'Heads-up: there is smoke in the kitchen. The alarm may sound..." [i.e., Someone is trying to make toast on the gas stove...] This beats the heck out of trying to figure out where the piercing alarm is coming from, and why...

They are sophisticated in every way desired for a boat. [We have 4 and counting, covering all occupied areas below deck, and the engine room...]

Study the features and see if this is what you are looking for. [No monthly fees... even though ours is set up to remote notify our phones if the boat WiFi is connected to the internet...]

I found multi-packs [3, 4, 5, etc.] on Amazon for sub US$100 each ~2 years ago.

Cheers! Bill

[FlyingScot]

Originally Posted by wrwakefield

Chris,

We installed the battery powered version of Nest Protect combination Smoke and CO alarms in our 43ft monohull [6- AA Lithium batts last 2+ years for us...] They network wirelessly using the boat's WiFi and each act as an announcer [spoken word] when one sounds an alarm.

I like it when the unit in our sleeping cabin anounces 'Heads-up: there is smoke in the kitchen. The alarm may sound..." [i.e., Someone is trying to make toast on the gas stove...] This beats the heck out of trying to figure out where the piercing alarm is coming from, and why...

They are sophisticated in every way desired for a boat. [We have 4 and counting, covering all occupied areas below deck, and the engine room...]

Study the features and see if this is what you are looking for. [No monthly fees... even though ours is set up to remote notify our phones if the boat WiFi is connected to the internet...]

I found multi-packs [3, 4, 5, etc.] on Amazon for sub US$100 each ~2 years ago.

Cheers! Bill

I hadn't considered these, but these look promising. Of course they cost more but might just be worth it.

Thank you for bringing these to my attention.

[Pelagic]

Those nest protect are interesting but I just wonder if they defeat the purpose of a high Decibel alarm to alert the neighbours at a marina or drydock

[GordMay]

Originally Posted by Pelagic

Those nest protect are interesting but I just wonder if they defeat the purpose of a high Decibel alarm to alert the neighbours at a marina or drydock

The Nest Protect has an emergency alarm horn, rated 85dB* SPL at 10 feet (3 m)
➥ https://support.google.com/googlenes.../9229922?hl=en

*The National Fire Protection Association (NFPA) mandates that a smoke alarm emit a sound that is a minimum of 75 decibels. The average smoke alarm in North America exceeds that by emitting an 85-decibel alarm.

[Tillsbury]

Originally Posted by Pelagic

Great Thread! Does anyone have Brand recommendations of trusted detectors (9v style)

Recommendations would be anything but the old 9v style ones.

[Pelagic]

Originally Posted by Tillsbury

Recommendations would be anything but the old 9v style ones.

Ok. tell me about the "anythings" you like? [emoji4]

[Tillsbury]

Originally Posted by Pelagic

Ok. tell me about the "anythings" you like? [emoji4]

Cavius are good: https://www.cavius.co.nz/

They started making what is now a “standard” smoke alarm, but have gone a bit high-end recently to maintain their prices I’d guess. So everyone else now makes them as well.

But you can still get the packs of the older style plain Cavius alarms, such as: https://www.mitre10.co.nz/shop/caviu...-pack/p/323091

That’s what I fit to any rental property, and did the same to the boat. One kitchen type, two normal in a pack.

[a64pilot]

Originally Posted by GordMay

Yes, carbon monoxide is slightly lighter than air*, and rapidly diffuses evenly throughout the room. Studies have shown no significant difference in measurements based on what height CO detectors are mounted. Different manufacturers recommend different mounting locations, and you should always follow the manufacturers’ recommendation.

*CO has a molar mass of 28.0, and air has an average molar mass of 28.8.

However that doesn’t take into account that most any source of CO will be heated well above ambient temp, and that will make it much lighter than ambient air, and in my opinion anyway makes a combo smoke and CO alarm an effective device, at least on my boat, I can’t think of a source of CO that isn’t from burning fuel of some sort.