billyfish
Active member
Where's yours, up top in the cabin or floor level or in between. My gas alarm is as low as can be but not sure Where's best for CM alarm its sort of head height between main cabin and sleeping cabin.
Top middle or bottom carbon monoxide
- Thread starter billyfish
- Start date
johnalison
Well-known member
Middle.
Gsailor
...
Oxygen is what we need to breath.
Two atoms weigh 32 units I.e. one molecule of oxygen
CO is 12 plus 18 = 30 units,
DON’T take my word on this - I just used Google - use it as a starting place only.
But the above would lead me to believe air (oxygen) is only slightly heavier than CO so I would place monitor / alarm at head height when sleeping and not down low.
I wonder if any of what I am thinking is correct?
Carbon dioxide will be heavier still.
Refueler
Well-known member
I have CO detectors in my house as we have serious wood fire system in kitchen - providing hot air to other rooms.
The detector instructions said to mount on a wall from mid height upwards.
I am surprised if OP's detectors do not advise on this ??
The detector instructions said to mount on a wall from mid height upwards.
I am surprised if OP's detectors do not advise on this ??
NormanS
Well-known member
Eye level.
Alicatt
Well-known member
Mine is at head height when standing
Sandydog2
Well-known member
Air is about 21% O2 (16x2) and 78% N2 (14x2) so an average of about 29 g/mol. CO is 12 plus 16 = 28 g/mol so is very similar to air. The usual advice is to put the sensor at the level you are breathing it at.
Gsailor
...
So head height when sleeping as I suggested would be ok?
That is where I used to keep mine.
They are cheap, perhaps place at two levels?
Alicatt
Well-known member
I can remember introducing the first CO detectors made by Thorn Security in conjunction with Aberdeen University, there was a lot of resistance to them at the start from "knowledgeable sources" Thorn Security was at that point taken over by Tyco and absorbed into ADT Fire & Security, I had to go around and do the presentation to Fire brigades and anyone else that would listen.
I used to have that introduction power point presentation (well it was the 1990s) but I scrubbed that HDD a good while ago.
From memory was that CO readily mixes with air and the advice at that time was free placement of the detector, I have been retired from the security industry for about 18 years now so that advice may have changed.
I used to have that introduction power point presentation (well it was the 1990s) but I scrubbed that HDD a good while ago.
From memory was that CO readily mixes with air and the advice at that time was free placement of the detector, I have been retired from the security industry for about 18 years now so that advice may have changed.
Plum
Well-known member
I followed the instructions that came with my CO detector, somewhere in the middle. I also have a second one mounted in the locker where the eberspacher is mounted (i can still hear it from the cabin) which i hope will give me an advanced warning.
johnalison
Well-known member
Although heavy gases such as CO2 and butane tend to gravitate down, I don’t know but I would doubt if CO does the same, assuming a certain amount of air circulation due to heat and movement.
AntarcticPilot
Well-known member
As others have said, mid-level or above. Carbon Monoxide is about the same density as air - in fact, its density is identical to that of Nitrogen, and Nitrogen doesn't settle out of the air! However, all sources of carbon monoxide are hot, so the Carbon Monoxide will initially rise and be detectable high up before it reaches lower parts of the cabin; obviously the particular pattern of convection will affect the results in each case.
Mine lives next to the cooker on the work surface, as that's the only source of Carbon Monoxide.
Mine lives next to the cooker on the work surface, as that's the only source of Carbon Monoxide.
arcot
Member
Nearby unnoticed boat exhaust may invade a boat through hatches or open ports....
AntarcticPilot
Well-known member
True. The most likely source in that case would be running a generator in the cockpit; the exhaust of another boat is not likely to be close enough. And of course, all our diesel heaters have their exhausts carefully placed to avoid that, don't they?
Boathook
Well-known member
My CO is at high level and the instructions said fairly high i seem to remember. As usual on a boat, where you put things like this is dependant upon space and where it won't get damaged, etc.
billyfish
Active member
Thanks all, much as I thought, will sleep well tonight.
PaulRainbow
Well-known member
Fire Angel instructions state:
WHERE IN THE ROOM SHOULD I PLACE
THE ALARM?
For alarms located in the same room as a fuel-
burning appliance (for both wall and ceiling
mounted alarms) the following applies:
• The alarm should be at a horizontal distance of
between 1m and 3m from the potential source.
• If there is a partition in a room, the alarm should
be located on the same side of the partition as
the potential source.
• Carbon monoxide alarms in rooms with sloped
ceilings should be located at the high side of
the room.
In addition to the above the following must be
observed if the alarm is located on a wall:
• It should be located close to the ceiling.
• It should be located at a height greater than the
height of any door or window.
• It should be at least 150mm from the ceiling.
If the alarm is located on the ceiling:
• It should be at least 300mm from any wall and
any ceiling obstruction e.g. light fittings.
Alarms located in sleeping rooms and in rooms
remote from a fuel-burning appliance should
be located relatively close to the breathing
zone of the occupants
WHERE IN THE ROOM SHOULD I PLACE
THE ALARM?
For alarms located in the same room as a fuel-
burning appliance (for both wall and ceiling
mounted alarms) the following applies:
• The alarm should be at a horizontal distance of
between 1m and 3m from the potential source.
• If there is a partition in a room, the alarm should
be located on the same side of the partition as
the potential source.
• Carbon monoxide alarms in rooms with sloped
ceilings should be located at the high side of
the room.
In addition to the above the following must be
observed if the alarm is located on a wall:
• It should be located close to the ceiling.
• It should be located at a height greater than the
height of any door or window.
• It should be at least 150mm from the ceiling.
If the alarm is located on the ceiling:
• It should be at least 300mm from any wall and
any ceiling obstruction e.g. light fittings.
Alarms located in sleeping rooms and in rooms
remote from a fuel-burning appliance should
be located relatively close to the breathing
zone of the occupants
PaulRainbow
Well-known member
Absolutely, there have been cases where deaths have resulted in exhaust fumes from other boats. Indeed, there was a recent, tragic, case where two men died as a result of exhaust fumes from their own engine were blown under the cockpit canopy.
I was once working on a boat when the Co alarm went off because of fumes from a petrol generator on the boat next door.
billyfish
Active member
This is sll great . Mine is about 10" from the ceiling between the main cabin and sleeping area. So should be perfect
Refueler
Well-known member
I don't think there is any perfect position ... too many factors like airflow etc. can affect it ... all we can hope is that we get it as best as possible.