Necessary for CO detectors to be "for marine use"?

[Flatswing]

I have both on board, the home ones are slightly more sensitive. Mine only go off if the holding tank overflows (vinegar added): more commonly, I believe, battery charging is the culprit.

[KadeyKrogen38]

How much is your and your families lives worth? Is trying to save a few dollars worth the risk if wrong?

[jmschmidt]

In 1966 I paid $28 for a replacement bulb for the red rotating beacon on my Piper Cherokee. The exact same bulb was about a dollar as a break light on my car. I checked around and found out the both bulbs come off the same assembly line at the factory. Absolutely no difference except this bulb is listed on the FAA's TSO (Technical Standards Order) and sold in different packaging with the TSO number on it. True story, say "boat" or "airplane" and the price skyrockets. This is not a new phenomenon.

[BlackHeron]

Just because an item comes off the same exact assembly line doesn't mean they are identical.

Every production line has manufacturing tolerances. Often the production is graded during testing and some product goes into high-end tight-tolerance use and others are rejected as low-grade or "generic" and are destined to be a lower-quality product.

An item such as an incandescent light bulb may be sorted by many different standards and criteria, such as how straight the shell is interested onto the glass bulb, how straight the filiment(s) are inside the shell. How tight/loose the crimp is or how far off the shell size is from the ideal. Even the clarity of the glass may be tested and the finished product sorted -or special runs made with better glass or metal shells.

The filement resistance may be tested for its internal values and may be graded as to how close it matches the ideal. Certain batches may be subjected to much more intense random testing, or to destruction which may drive production costs further up.


Batches could be made with subassemblies that have been subjected to tighter tolerances and testing before final assembly on a machine that has recently been much more carefully adjusted or operated by the best or most experienced employees to maximize quality control.

That typical automotive bulb may be representative of 90% of the production of that factory where 5% of the product is rejected as unfit for sale or used in destructive quality-control testing. While at the same time the aircraft-grade items could have been skimmed only from the best 5% or even 1% of the items that came off of that same line or factory.

[Chotu]

I have used home detectors for at least 15, almost 20 years now.

Good ones with the ppm digital readout to ensure quality control of every situation.

Note: Hydrogen given off by battery charging will give you false positives.

[maelduin]

https://chemistry.stackexchange.com/...ses-other-than

[scottgledhill]

I had two Home Depot CO detectors. One left by previous owner and one I purchased. Both failed in shot time. Replaced with marine unit and no problems after 18 months of use.

[Jammer]

Originally Posted by KadeyKrogen38

How much is your and your families lives worth? Is trying to save a few dollars worth the risk if wrong?

I don't have a portable gasoline generator.


I don't have an inboard engine or stern drive that is gasoline powered.


I don't burn charcoal in the cabin.



Throughout the entire worldwide history of boating I do not believe there has ever been a single fatality attributed to CO poisoning aboard that did not involve one of these things.

[David B]

Originally Posted by Rohan

CO detectors labeled "for marine use" cost like 5 times as much as standard CO detectors at your local hardware store (like $100 vs $20 here in the US). I can't find anything on the difference between the two except that apparently the "marine use" certified detectors are tested under slightly more rigorous conditions like a rapid change in temperature (neither types are waterproof).

The difference in price is not earth shattering, but this is kind of a moral principle. I'm just kind of fed up of generators, refrigerators, etc everything being wildly more expensive simply because they are built for boats.

Is this legit, or another way to soak us for $$?

Marine use versions should have conformal coating on the PCB, but really, that is not worth more than a few cents.
We use four First Alert domestic units on our boat. Neat, small package that fits nicely above the door frames. From memory they were around USD 10-15 each in a twin-pack. May have been less, but they are UL (amongst other things) certified, so that's good enough for me.

At that price, I bought an extra twin-pack to give us a couple of spares.

[wingless]

Originally Posted by David B

Marine use versions should have conformal coating on the PCB, but really, that is not worth more than a few cents.

An aerosol can of conformal coating was purchased years ago to permit disassembly, masking then protecting circuit board assemblies on new products. They are then reassembled and put into service.

[ArmyDaveNY]

Originally Posted by ArmyDaveNY

Not surprisingly, there was no answer. Either they were very busy or they are not in the office due to the Wuhan virus. I sent an e-mail to the Sales@FirstAlertStore.com requesting an answer.

My first post was #10 where I mentioned calling First Alert. I have not received a written answer but today I did speak to someone in tech support. This person was not terribly knowledgeable however she did ask someone in the office. The end result was no one was able to state what the difference was. A few took guesses and finally the answer was that they don't make marine units.


I called MTI and Fireboy, both of whom make and sell "marine" units. No one was in the office so I sent them each an e-mail asking what the difference is. I will post an update if and when I receive an answer.

[Sailing Drummer]

The question was is it “necessary” for them to be for marine use. I guess that depends on your level of what’s necessary. There is a different UL rating for marine. It’s safer in our harsh world. Can you get by with a home unit? Of course you can, until someone dies or sues you! And good luck with your insurance company paying any damages. The reason you get one is to be safe. Why get one that’s not UL rated for vessel use? Just to save a little $$$?

[Tin Tin]

Originally Posted by Jammer

I don't have a portable gasoline generator.


I don't have an inboard engine or stern drive that is gasoline powered.


I don't burn charcoal in the cabin.



Throughout the entire worldwide history of boating I do not believe there has ever been a single fatality attributed to CO poisoning aboard that did not involve one of these things.

Two other killers are Diesel and Propane. People have died on boats using the propane stove to warm the cabin. A Trucker died from CO poisoning asleep in his Cab with diesel engine running, not heard of a case on a boat, though I do recall some fishermen died from CO, but not sure of the source.

[ArmyDaveNY]

Originally Posted by Sailing Drummer

The question was is it “necessary” for them to be for marine use. I guess that depends on your level of what’s necessary. There is a different UL rating for marine. It’s safer in our harsh world. Can you get by with a home unit? Of course you can, until someone dies or sues you! And good luck with your insurance company paying any damages. The reason you get one is to be safe. Why get one that’s not UL rated for vessel use? Just to save a little $$$?

What is the difference between a UL "marine" rating and a standard rating?

If the difference is just a longevity issue then the home units will work just as well but perhaps not as long. If there is actually a performance difference then your comment is valid.

ANSI/UL 2034 standard covers electrically operated single and multiple station carbon monoxide (CO) alarms intended for protection in ordinary indoor locations of dwelling units, including recreational vehicles, mobile homes, and recreational boats with enclosed accommodation spaces and cockpit areas (per the standard). This implies that from a performance point of view there is no difference.

Is there actually a performance difference?

[ranger58sb]

Originally Posted by ArmyDaveNY

I called MTI and Fireboy, both of whom make and sell "marine" units. No one was in the office so I sent them each an e-mail asking what the difference is. I will post an update if and when I receive an answer.

Several years ago, MTI told me on the phone that their marine unit and RV units were exactly the same except for labeling.

I had made the mistake of inadvertently buying RV ones, online. Eventually called MTI to ask about it, and they offered to swap me for marine units... but given they were the same, and I had already installed at least one of the RV ones... I just went with those.

-Chris