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According to the CDC, you should "NEVER use a gas range for heating".

Never use a gas range or oven for heating. Using a gas range or oven for heating can cause a build up of CO inside your home, cabin, or camper.

Is this valid advice though? Is there any evidence that a gas range not used for cooking is a danger to the household when only burning gas with an open flame? If so, how many hours of use is required for this danger to manifest?

And also the EPA provides similar guidance,

Using a stove hood with a fan vented to the outdoors greatly reduces exposure to pollutants during cooking. Improper adjustment, often indicated by a persistent yellow-tipped flame, causes increased pollutant emissions. Ask your gas company to adjust the burner so that the flame tip is blue. If you purchase a new gas stove or range, consider buying one with pilot less ignition because it does not have a pilot light that burns continuously. Never use a gas stove to heat your home. Always make certain the flue in your gas fireplace is open when the fireplace is in use.

Fizz
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Evan Carroll
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  • https://ajph.aphapublications.org/doi/pdf/10.2105/AJPH.13.6.462 – DavePhD Feb 18 '21 at 02:01
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    You seem to have answered your own question. – Schwern Feb 18 '21 at 03:40
  • Regardless of the danger, it's also very innefficient. If you're exhausting the combustion gasses (which you should absolutely do), you're heating the outside. Gas furnaces are optimized to maximize heat transfer into interior air without having you breathe CO. – JS Lavertu Feb 18 '21 at 15:20
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    Yes, it is valid advice that you should never do that. Sure, there are plenty of cases when people will survive (even without repercussions) even when doing something dangerous/stupid. That does not invalidate a claim that "you should never do it". There are people who survived falling out of airplane without parachute. Still, it is valid advice that "you should never jump from airplane without parachute". Same here. – Matija Nalis Feb 18 '21 at 16:05
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    Curious why you'd think both the CDC and EPA would put out incorrect information about this. I'd say those are about as trustworthy a source as any. What source would you accept over those two? What about [D.C.'s government page](https://ota.dc.gov/release/dangers-using-your-stove-home-heating)? Have you found a source saying it's not dangerous? – BruceWayne Feb 18 '21 at 22:07
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    @JSLavertu, efficiency is generally not the primary consideration when the alternative is freezing to death, which is generally the sort of situation where people start considering stuff like this. – Nate S. Feb 18 '21 at 23:17
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    This seems like a perfect example of when a harm reduction approach should be used, instead the CDC advocates abstinence approach under the misguided idea that if you withhold information people won't do the thing you don't want them to do. This is completely incorrect-- people do the thing anyway, but without any knowledge whatsoever instead of making informed risk-choices. When people do resort to this it's, as @NateS says, because the alternative is also quite bad. It's easy to say never do this if you've never lived in an apartment where the heat was out for days to weeks on end. – eps Feb 19 '21 at 01:26
  • @BruceWayne a perfect example of what i'm talking about. The DC advice clearly recognizes the principal of harm reduction -- they recognize the reality of having lots of people living in places where the heat regularly goes out and realize that "just say no" doesn't work; instead they offer solutions that recognize that sometimes people are forced to choose the best among bad options. – eps Feb 19 '21 at 02:21
  • @eps hm true. However, for OP's title question, the DC site says very explicitly, "Don’t Even Try. NEVER USE YOUR OVEN FOR HEATING. Kitchen ovens were never designed for heating homes only for cooking food. ". So yes it is dangerous. – BruceWayne Feb 19 '21 at 02:34
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    @BruceWayne Sometimes government agencies may overstate risks, not because behaviour is inherently dangerous but because many people misapply a technique and /then/ it becomes dangerous. – gerrit Feb 19 '21 at 13:46
  • @Nate Good point, I didn't think about that. – JS Lavertu Feb 19 '21 at 16:04
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    Is it ok to just bake turkeys 12 hours a day? – Ask About Monica Feb 19 '21 at 18:06
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    I have a feeling this is the wrong question. Is it more dangerous than risking hypothermia? may be a better question. – user_1818839 Feb 20 '21 at 16:49

4 Answers4

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Yes, because the safety systems that are required for furnaces and water heaters are not standard on stoves and ovens.

Conventional gas-burning furnaces and hot water heaters include two design elements to prevent build-up of carbon monoxide (poison hazard) and natural gas (explosion hazard) inside the house:

  1. A flame sensor checks if the gas is burning. If it is not, the gas valve closes. This way, if the flame is extinguished, the appliance will not continue releasing natural gas into the house.
  2. Combustion gases are exhausted outdoors through an exhaust flue. The gas is burned in a sealed chamber that is vented to the outdoors -- the air or water being heated passes through a heat exchanger in the combustion chamber.

Even with these two systems in place, CO detectors are still required, and odors are added to natural gas to make leaks detectable.

By contrast, a natural gas-burning stove or oven has neither of these safety measures (some newer models may have flame sensors*, but most existing ones don't). If the flame goes out the gas keeps coming, and the combustion gases are released directly into the living space. An exhaust hood will remove the combustion gases, but also most of the heat.

If you are using the oven/stove as intended, you are likely in the kitchen where you will be able to smell the natural gas, or see that that flame is yellow and/or smoking, an indication of the incomplete combustion that can generate CO. You will also not be using the appliance for several hours every day (or if you are, you are likely using an exhaust hood).

*In the U.S. and Canada, CSA/ANSI Z21.1-2018/CSA 1.1-2018 is the standard for "household cooking gas appliances". If someone has institutional access they could check if flame sensors are required, but this would be a recent change.

LShaver
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    Note that some gas stoves (in fact all that I have personally seen and used in Europe) do have a flame sensor working exactly as you described. The combustion gases are still in the kitchen though, so that points is still valid. – quarague Feb 18 '21 at 08:37
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    Point 2 is the relevant one with regard to CO levels. Point 1 mostly makes it harder to accidentially blow the building up (and is also available in all stoves I have seen so far, except perhaps some camping equipment). – Hulk Feb 18 '21 at 09:00
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    @quarague I'm in Europe too, but there are plenty of older gas stoves/ovens around here that don't have them. If I recall correctly they only became mandatory on new equipment sometime in the 1990's. My stove and oven don't have them and they are from 1984. Will finally be replaced this summer when I remodel the kitchen. – Tonny Feb 18 '21 at 12:44
  • @quarague good point -- I've never seen one with that feature, but it makes sense that they would be required in some places. I've updated the answer. – LShaver Feb 18 '21 at 15:50
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    I'm pretty sure that all gas ovens sold in the last 40 years in the US have included mechanisms to limit the amount of gas released if the flame goes out, even though stovetops generally don't. I think the rationale is that ovens are commonly used to bake things for long periods of time and are consequently expected to be left unattended while in use, but stoves are not. I don't know if they would completely shut off gas, but they would at most operate a small pilot light and then only feed gas to the main burner while the pilot light is lit. – supercat Feb 18 '21 at 18:48
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    @LShaver the ANSI standards are purely voluntary in the US, so even if they mention sensors, sensors would still not be "required". – DavePhD Feb 18 '21 at 19:13
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    This seems like the CDC is greatly overexagerating the actual risks, assuming you aren't leaving the thing running overnight or walking away for hours on end. I don't know of any cooks who monitor their stove all day when making stock or a stew, because I can count on zero hands the number of times the gas has gone out on a modern stove. But the problem with this approach is that it pretends their are no risks associated with being in a literally freezing house for days on end. People aren't doing this out of mild discomfort, and thus a relative risk approach must be undertaken. – eps Feb 19 '21 at 01:47
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    @eps, note that in the context of the current winter storm in Texas, it is actually a whole lot more likely than normal that the gas might cut out temporarily, since there are supply problems with the gas infrastructure as well (which is a big part of why the electricity is out). Normally I'd agree with you, but in this situation it would be a good idea to monitor it more closely than normal. – Nate S. Feb 19 '21 at 18:09
  • Europe here, the oven I have is decades old, and it does have a flame sensor for the oven bit (which is fun because you have to hold the gas knob with one hand, and strike your match with two other, or fiddle with the knob with an already lit match). The burners don't, though, and I can imagine a burner in disrepair would be prone to dying occasionally. – John Dvorak Feb 20 '21 at 11:53
  • In 40+ years of owning various homes with various gas stoves, I've never had one with either a flame-out sensor or an externally-vented hood. I'm still alive. The claim is 'true' for a given value of 'true'. – Tetsujin Feb 20 '21 at 16:57
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According Non-Fire Carbon Monoxide Deaths Associated with the Use of Consumer Products 2003 and 2004 Annual Estimates by the U.S. Consumer Product Safety Commission:

In the US, deaths due to CO from "Gas Ranges/Ovens" were:

1999: 6
2000: 12
2001: 9
2002: 3
2003: 3
2004: 4

According to Carbon Monoxide Poisoning: Gas-fired Kitchen Ranges:

51 percent of kitchen ranges tested raised CO concentrations in the room above the EPA standard of 9 parts per million. Five percent had carbon monoxide levels above 200 parts per million

Also, death can occur due to using up too much of the oxygen in the combustion, as explained in Mother and 2 Infants Found Dead, and Use of Stove for Heating Is Implicated New York Times 10 January 1998.

DavePhD
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    Deaths are only part of the issue. There are reports of more than 300 cases of CO health issues in Texas during the recent weather events (and a few CO related deaths as well) – alephzero Feb 18 '21 at 14:50
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    MMWR has some confirmed cases of death, but from using gas burners (or even charcoal grills) inside tents https://www.cdc.gov/mmwr/preview/mmwrhtml/mm4832a1.htm @alephzero: CO poisoning can result from appliances intended for heating alas, as this older MMWR report details: https://www.cdc.gov/mmwr/preview/mmwrhtml/00039315.htm – Fizz Feb 18 '21 at 21:57
  • And on note with hypoxia (lack of oxygen), your body does **NOT** detect lack of oxygen, but a build-up of carbon dioxide (CO2). The gas stove using up too much oxygen, and then creating CO (which your body does **NOT** detect that well), you will simply get sleepy, go to sleep, and die. – Nelson Feb 20 '21 at 08:53
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The CDC and the EPA are generally correct. However, they say "never."

In a place that is not sealed against external air or has adequate ventilation, you can use an unvented gas heater. There are camping heaters for this purpose.

When I was a graduate student and for some time afterwards, I lived in a drafty old house that was heated with old gas space heaters. Because there was outside air coming in they were fairly safe. I had no need to use the gas stove for heat because whatever heat these primitive units produced eventually made its way to the kitchen and was vented up into the attic.

In a later house, we sometimes used the gas stove for heat, because it didn't have any other heat. This was in Texas. The house had 4 bedrooms, 3 poorly sealed outside doors, and one could feel cold outside air coming in around the windows and through the electrical outlets. Otherwise, what it needed, except a few days a year, was cooling, not heating. A girlfriend ruined the gas oven by turning it on for heat and leaving the door open, which of course blew the thermostat.

I don't intend to contradict any of the other answers, which are correct, only to suggest that not every rule, even from the CDC and the EPA, applies 100% of the time.

Wastrel
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    All in all, this answer seems to come down to an anecdote of "I've done X several times and survived", which does not answer how dangerous X is. – Hulk Feb 18 '21 at 16:32
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    The product you linked says not to use indoors or in sealed spaces. – Joe W Feb 18 '21 at 20:22
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    _"Especially as CO and CO2 may accumulate near the floor of the room ..."_ - Why would CO accumulate near the floor of the room? It's very slightly lighter than air, but the difference is so small that it distributes itself evenly. – marcelm Feb 19 '21 at 11:11
  • @marcelm you are right, I misremembered that - CO is indeed (slightly) lighter than air. Removed that comment with this wrong claim. – Hulk Feb 19 '21 at 11:58
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    @Joe W It would be fine for the typical "tumbledown shack in Bigfoot county." These guidelines, like the ones from the CDC and EPA, are stated as absolutes but in reality apply only to the modern more-or-less hermetically "sealed" houses and apartments. And also offices, where you can't even crack a window. – Wastrel Feb 19 '21 at 13:41
  • That isn't what the question is asking about. It is asking about using them in a general sense and it would include many more situations that would be dangerous. More people live in places where it would be dangerous than those that don't. – Joe W Feb 19 '21 at 13:55
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    Welcome to the site. Answers here must be based in scientific analysis, properly sourced, and cited if necessary. Personal experience is not what is sought here. Now, the existence of the gas space heaters is a good start, imo, and "use with enough ventilation" seems obvious to me, but that doesn't satisfy the site rules. You'd need to follow with evidence regarding that ventilation, but will probably be tough since those items are explicitly for outdoor use. You'll have to edit this answer to prevent it's deletion. –  Feb 19 '21 at 15:04
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Gas ranges are dangerous even for cooking!

(Other risks like fire, explosion or CO poisoning are also easilly found to be higher from numerous sources.)

Gas heaters for use without dedicated ventilation do exist, but they have flame-out protection, low oxygen protection, topple protection and are built with less attentive use in mind. Most of them are catalytic, meaning no free flame and low CO as well.

On the other hand, the only safety feature in a gas stove I have ever seen is a flame-out protection. Good, but not enough to sleep around it.

fraxinus
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    Welcome to Skeptics.SE. Google searches are not a substitute for reliable sources for answers, they're generally fodder for more questions, and it does not address the question. Stay focused on the question, not a general discussion of gas vs electric, and away from tangents. – Schwern Feb 18 '21 at 20:50