Are electric homes safer than homes with gas?

For homeowners who are switching from gas to electric appliances or designing an all-electric home, the health benefit is clear: the air quality in an electric home is better, especially when taking into consideration cooking with electricity instead of gas. While cooking with any type of fuel, including electricity, will release particulates into your kitchen air, gas stoves produce higher quantities of fine particulate matter (PM_2.5) as well as other pollutants such as benzene and nitrogen dioxide (NO₂).

But what about other hazards, such as fire safety? It turns out that electric homes have an advantage there too because of safety features in modern induction cooktops, such as high temperature auto-shutoff. According to data from the United States, cooking is the cause of half of house fires, so switching to induction can significantly cut the risk.

Switching to a heat pump from a gas furnace will also improve safety by eliminating a major source of carbon monoxide as well as the potential for natural gas leaks. Compared to other types of heating equipment, a heat pump can also improve fire safety, although the data is a little less clear about that.

Finally, about 9% of house fires can be traced back to electrical and lighting equipment. One concern that a homeowner might have is that adding electrical loads would increase this risk. However, the available data indicates that most electrical fires can be traced back to faulty wiring and equipment rather than high loads.

This is an important issue for many homeowners who are thinking of switching appliances from fossil fuels to electricity, so in this article I’ll do my best to present the available data.

Indoor air quality is a hidden risk for many homeowners

From a health and safety perspective, electric homes have one indisputable advantage: better air quality. It’s a big enough issue that I wrote a whole article on it, which I encourage you to read if you have concerns about indoor air quality.

The brief summary is that poor indoor air quality is a bigger issue than most homeowners realize. As many as 1 in 8 cases of childhood asthma can be traced back to pollution from a gas stove in a home. Adults with COPD and other vulnerable individuals can also be at risk.

The issue is that gas stoves emit pollution like PM_2.5, NO₂ and benzene both during operation and even when shut off. Studies have show that nearly all gas stoves leak to some degree. Because natural gas isn’t pure methane but contains trace contaminants such as formaldehyde, there’s a health risk due to chronic low-level exposure to these airborne chemicals.

The other major air quality risk from appliances powered by heating oil and natural gas is the risk of carbon monoxide (CO) poisoning. Poorly tuned equipment that operate with incomplete combustion can produce CO, but CO can also enter a home due to backdrafting, which can happen when kitchen and bathroom exhaust fans generate negative air pressure and pull exhaust from a furnace or hot water heater into a house.

That’s why carbon monoxide detectors are important: you can read more about the need for CO detectors, even in an all-electric home, in my article on the topic.

The bottom line is that electrical appliances don’t rely on combustion, and therefore don’t produce hazardous pollution that can sicken, or in the extreme case of carbon monoxide poisoning, even kill homeowners.

Half of all house fires are cooking-related

The best data available on the cause of house fires in the United States is from the National Fire Incident Reporting System (NFIRS):

The NFIRS represents the world’s largest national annual database of fire department incident information. Each year, approximately 23,000 fire departments from all 50 states and the District of Columbia voluntarily report data on one million fires and 22 million other fire department-responded incidents, such as hazardous material incidents or smoke scares.

According to the National Fire Protection Association that manages this database, NFIRS is not a census of all fires and doesn’t reflect every fire that occurs in the country. That said, NFIRS contains data on hundreds of thousands of fires, and provides excellent insight into the causes of house fires.

The biggest cause of house fires by far is cooking, accounting for half of all fires. This surpasses heating equipment as the second most common cause (at 13% of fires), followed by other causes such as wiring, candles, smoking, and clothes dryers.

The data goes into further detail and indicates that cooktops are the main source of cooking-related fires. This makes sense, given that non-induction cooktops all rely on a hot cooking surface or open flame.

Here’s the data from NFIRS on the source of cooking-related fires:

More than a quarter of all house fires can be traced back to a stovetop. Unfortunately the data doesn’t go into further data about the type of cooktop that was used in these fires, but one thing we know is that very few of them would be induction cooktops. That’s because few homes have induction appliances installed, though that number is growing. Also, the NFIRS data is from 2015–2019, which precedes the interest in induction appliances in recent years.

Oven fires represent the second largest cooking-related cause of house fires, followed by portable devices (which includes butane-powered burners and chafing dishes heated by burning alcohol), microwave ovens, and outdoor grills.

Induction cooking is much safer than gas or conventional electric

While there isn’t enough data in NFIRS to determine whether an electric oven poses any less fire risk than a gas oven, it’s definitely the case that an induction cooktop poses a lower fire risk than both gas and conventional electric cooktops.

This is because induction cooktops don’t use an open flame (in the case of gas) or hot heating element (in the case of conventional electric) to heat a cooking vessel. Instead, induction cooktops use a magnetic field to heat compatible cookware directly. The surface of an induction cooktop doesn’t provide \ heat directly, and will only get warm due to contact from the hot cookware sitting above. A large coil in an induction burner creates a magnetic field that in turn generates electrical eddy currents in the cookware, which creates heat due to high resistivity in the metal¹.

As a result, induction cooktops are inherently safer than cooking with an open heat source. The cooktop and cookware will be at a much lower temperature than an open flame, minimizing the risk of anything inadvertently catching on fire. You’ll be familiar with this risk if you’ve ever accidentally singed a pot holder on the open flame of a gas stove.

Another safety feature that induction cooktops have is temperature sensing. Sensors can be used in couple ways that improve safety. One feature is automatically holding a cooking vessel at a set temperature. This makes it easy to keep a pot simmering at a safe temperature for a long time - the sensor will detect the temperature of the pot sitting on the burner and automatically adjust the power output to maintain that temperature.

These sensors are also used to prevent cookware from getting dangerously hot. For example, if you’re simmering a pot on a gas stove and the pot boils dry, it can quickly get to a dangerous temperature. However, the sensors in an induction cooktop will detect when this happens and shut off the power before the temperature gets too hot. All induction cooktops have this safety feature - even low-cost single burner models.

House fires caused by heating equipment

After cooking, the second largest cause of house fires is heating equipment. This is a broad category that includes furnaces, but also portable space heaters and fireplaces.

Not surprisingly, fireplace and chimney fires are the most common cause of heating equipment-related house fires. Here’s a table with data from NFIRS on heating equipment-related fires:

The second largest cause is space heaters. This includes both electrical and kerosene space heaters. The data doesn’t show how many fires are caused by electric or kerosene heaters, but both generate heat using either an open flame or hot element. NFIRS notes that there has been a gradual reduction in fires caused by space heaters since 2000, likely due to safety standards such as automatic cutoff when kerosene heaters are tipped over and better protection around electric heating elements.

A smaller number of fires were attributed to central heating and water heating. The NFIRS reporting only mentions that homeowners should ensure that this equipment is well maintained, and doesn’t go into further detail to explain whether the heaters were natural gas, heating oil, or electrical.

Heat pumps are a safer way to heat and cool a home

Compared to fireplaces and portable space heaters that use an open flame or a heating element that can come into contact with flammable materials, a heat pump is a much safer way to heat a home.

This is especially true if you want extra heating in certain areas of your home. Fireplaces and portable space heaters are often used for this reason - maybe you spend most of your time in your living room and prefer to use your fireplace to keep you warm.

Heat pumps are a safer option for this purpose, especially ductless mini-splits. With mini-splits, you install indoor units in the locations where you need them. You can heat an entire home with this type of system, but they’re also a good option if you have an existing heating system (such as a central furnace) that doesn’t quite heat all areas of your home very well. (This is common in older and poorly insulated homes.)

Instead of upgrading your entire heating system, you could use a mini-split heat pump system to add supplemental heating in just the rooms that are cold. This is less expensive than a complete furnace upgrade, and a safer way to heat individual rooms than a fireplace or space heaters.

Of course, a mini-split system can be used to heat an entire home as well. Along with safety, another major benefit is that mini-split systems give you individual control over the indoor units, so you can fine-tune the temperature in every zone in the system.

Finally, heat pumps also act as air conditioners in the summer - something that your furnace, fireplace, or space heater can’t do.

With federal incentives from the Inflation Reduction Act, heat pumps are seeing a surge in popularity in the United States. They’re growing in popularity around the globe too, in part because of efforts to phase out fossil fuels, but also because they’re highly efficient and clean. You can read more about heat pump basics or learn about the difference between central and mini-split heat pump systems in articles I’ve written.

Can heat pumps catch on fire?

Unlike heating systems that use an open flame or heating element, heat pumps use the refrigeration cycle to move heat from one place to another. In heating mode, a heat pump will take heat energy from outside your home to the inside. When operating as an air conditioner, the process is reversed, and heat is taken from inside and moved outside to cool your home.

This means that in normal operation, no components in a heat pump will get hot enough to cause combustion of anything they happen to get in contact with.

What about electrical faults? The NFIRS database doesn’t have any data on fires caused specifically by heat pumps. The closest is fires that involve air conditioners. According to the data, an average of 2,800 out of 346,800 fires can be traced back to an air conditioner, or about 0.8%. The data doesn’t distinguish between window and central conditioners.

This is less than the number of fires attributed to lighting (4,300), and certainly far less than the number of fires caused by heating equipment (45,800). However, it’s not zero, so there is some minimal risk. There’s no further detail from NFIRS as to why air conditioners are occasionally involved in house fires, but if I were to make an educated guess, I would say that most are due to faulty wiring or poor installation practices.

The bottom line is that while heat pumps, like any electrical equipment, can potentially catch fire, the risk is far less than other types of heating equipment.

Safety tips for all-electric homes

According to the NFIRS database an average of 21,900 house fires, or 6% of all fires, can be attributed every year to “wiring and related equipment”. This doesn’t mean that electrical appliances have some inherent risk that should be avoided, but rather that electrical wiring and equipment needs to be installed by a qualified contractor and properly inspected.

According to the electrical safety group Underwriters Laboratories, a homeowner can greatly reduce their risk of an electrical fire by keeping an eye out for warning signs such as flickering lights, sparking or buzzing from electrical equipment, and frequently tripped breakers or fuses².

Notably, UL does not state that having more electrical equipment or high amperage equipment (such as heat pumps or EV chargers) poses an inherent risk to a homeowner.

Yes, all-electric homes are safer

It’s clear that all-electric homes are safer than those that use fossil fuel-powered appliances. The advantage is certainly apparent for indoor air quality by eliminating pollutants such as nitrogen oxide and formaldehyde, but also carbon monoxide, which kills at least several hundred people in the United States every year.

House fires are the other major risk that all-electric homes reduce. Specifically, an induction cooktop is much safer than cooking with gas. Induction cooking doesn’t use an open flame, but also has sensors that can shut off the appliance when it becomes too hot.

This is not to say that electric homes have zero safety risks. As pointed out by UL, proper installation and inspections are crucial for homeowner safety.

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