Smoke Detector types and mounting location best practices

[FlyingScot]

In the spirit of learning from tragedy, I feel now is the time for me to install multiple smoke detectors.

I am interested in hearing what others use and where they mount them.

My particular case is a catamaran with isolated engine rooms. Inside the boat, we have 3 cabins, two separate heads and the salon. Eight smoke detectors in a 40' boat seems like overkill.

I want them to interconnect in such a way as for one alarm to set off all the alarms. My boat isn't prewired for any, so this functionality will be wireless. This wireless function will eat up batteries.

Then there is the issue of type: Ionization vs photoelectric.

[Tillsbury]

I use the standard modern 10-year ones. There's nowhere on my boat that one wouldn't be seriously audible from anywhere, so just put them in any old where. Kitchen type above the galley.

[Paul L]

I prefer the combo fire and CO detectors

[Tillsbury]

The 10-year ones have recently become mandatory in rental properties over here, so have dropped somewhat in price. I use the combo gas/co marine alarm, as well as a separate gas detector in the galley, so stick to heat and smoke for the ceiling mounted fire alarms. Recently installed battery temperature alarms as recommended for $3 each by Dockhead (I think, was it?), so pretty much alarmed up now...

[GordMay]

Ionization smoke alarms tend to respond faster to the smoke produced by flaming fires, than photoelectric smoke alarms.
Photoelectric smoke alarms tend to respond faster to the smoke produced by smoldering fires, than ionization smoke alarms.
In some full-scale fire tests, the difference in the time to alarm, between ionization and photoelectric smoke alarms, was found to be trivial. In other full-scale fire tests, the difference in response time was considerable.
Because no one can predict* what type of fire might start in a home or boat, I recommend that every place where people sleep be equipped with either:
(a) both ionization and photoelectric smoke alarms,
or
(b) dual sensor smoke alarms (which contain both ionization and photoelectric smoke sensors).

* According to the Government of Canada, approximately 70 percent of home fires that take place in the country are the flaming type, or those in which a fire ignites quickly. It's for this reason that most homes are outfitted with ionization type alarms.

[kas_1611]

We have a single, standard 9v battery powered smoke detector mounted midships in the saloon area. 40ft mono but trust me you hear it going off when the toast burns a mile away in an anchorage.

Would change it out for a combo smoke/CO detector especially if I can find one with a manual over ride or "kitchen" feature.

With the 9v battery we can remove the power source easily and the entire unit just unclips from the mount which is the best way to stop it going off with the toast.

Given I only have to have 2 mains powered smoke detectors in my 5 bed house (although we have 3 as we have a granny annexe with it's own unit) you don't need to have more than 1 in an boat although I can see why you might want 2 in a cat for the separate engine areas.

[FabioC]

I use separate smoke and CO alarms (the battery powered ones from West Marine). I have two of each, even if it is not a large boat (34' sailboat). One pair near the engine (which is also near the cabin where we sleep), one pair in the saloon in the vicinity of the galley. I think more than one pair is needed because a boat does not have "ideal" spots to place the detectors, so placement is always a compromise. I also think that separate smoke and CO detectors are preferable than a combo one because you can optimize the placement of each.

[Canarios]

Originally Posted by FlyingScot

In the spirit of learning from tragedy, I feel now is the time for me to install multiple smoke detectors.

I am interested in hearing what others use and where they mount them.

My particular case is a catamaran with isolated engine rooms. Inside the boat, we have 3 cabins, two separate heads and the salon. Eight smoke detectors in a 40' boat seems like overkill.

I want them to interconnect in such a way as for one alarm to set off all the alarms. My boat isn't prewired for any, so this functionality will be wireless. This wireless function will eat up batteries.

Then there is the issue of type: Ionization vs photoelectric.

Hi I have a lagoon 380. Installed two pairs. One in each engine room. Each seperatly connected to a twin on each side of the cabin roof in order to understand which engine room the fire have started. We never close doors to the sleeping cabins unless people are there. This twin systems we think is the best solution.

[Pelagic]

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

[Canarios]

Originally Posted by Pelagic

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

Best to buy two pairs of those detectors you use in you hone with a battery in each unit.

[Paul L]

Originally Posted by Pelagic

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

Not sure why you would want 9v batteries. They are harder to source when cruising and don't have any advantage over AAs. We use rechargable AAs in our fire/CO detectors.

[roland stockham]

Not my area of expertise but I would think about 2 things. I think carbon monoxide sinks, if so that one needs to be low down. Second how does the air flow? Mayby use a smoke source to track it and place detectors along the route from fire risks to sleeping areas. On a cat I would think three are needed, one in the saloon and one in each hull plus CO in each hull.

[sailorboy1]

[QUOTE=FlyingScot;2997360]

I am interested in hearing what others use and where they mount them.
/QUOTE]

I used to have one of those standard marine units that I had to wire into the power system. Now I have 2 modern units with 7 year batteries that Ijust attached with doubleback sticky tape.

[sailorboy1]

Originally Posted by roland stockham

I think carbon monoxide sinks, if so that one needs to be low down..

= 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.

[a64pilot]

Add in the fact that almost certainly the source of CO in a boat is burning fuel, which means it’s heated, that will also make it significantly lighter than air.
For that reason it’s best to mount them high, and combo smoke / CO detectors work well mounting location wise. however a propane detector should be mounted low