Airbnb’s silent killer: 19 carbon monoxide deaths in the last 10 years, but the company still doesn’t require detectors

In February 2014, Airbnb made a commitment: The company would require hosts to confirm that carbon monoxide detectors were installed in every listing by the end of the year.

Months earlier, the short-term rental company faced one of its first reported deaths involving carbon monoxide: a Canadian citizen staying in an Airbnb in Taiwan. The company wanted to do more, it said in a now-deleted blog post.

“By the end of 2014, we’ll require all Airbnb hosts to confirm that they have these devices installed in their listing,” the blog post said of carbon monoxide detectors.

Nearly a decade later, the company has not made any such mandate — and more lives have been lost along the way.

NBC News has identified 19 deaths since 2013 that occurred at Airbnb properties and are alleged to have involved carbon monoxide poisoning, according to interviews with family members of victims and a review of news articles, autopsy reports, police records, and court and government documents. The company is currently facing at least three lawsuits pertaining to carbon monoxide deaths or poisonings.

Airbnb has issued statements in seven of the cases, which accounted for 17 of the deaths.In five of the statements, Airbnb said it would pay for costs associated with the deaths or that it had removed Airbnb listings associated with the incidents. None of the statements contested details of the reports surrounding the deaths, and none addressed carbon monoxide’s role in the incidents. Other statements expressed condolences. In the two cases in which the company has not commented, Airbnb was the target of lawsuits. One of those suits was settled and the other was dismissed.

In a statement provided to NBC News, the company said: “The safety of our community is a top priority, incidents on Airbnb are exceptionally rare and we take action when a concern is reported to us.”

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Family members and representatives of people who died said Airbnb has not done enough to address the situation and called for the company to commit to a mandate that carbon monoxide detectors be installed in every rental. Some said Airbnb promised to work with them but that they now feel brushed aside.

Jennifer Winders, whose father and stepmother died from carbon monoxide poisoning in an Airbnb in Mexico in November 2018, said that the company agreed to meet with her and her brother on potential safety improvements as part of a settlement that included financial compensation.

Winders said they had one meeting in February 2022 with the company where they gave suggestions.

Ed Winders and his partner, Barbara Moller, died from carbon monoxide poisoning while vacationing in Mexico.Courtesy Jennifer Winders

“I feel like that’s something that would be really beneficial is to have Airbnb continue to reach out to people who are continuing to feel the effects of what happened in one of their rentals,” she said. “I wonder after seeing all these deaths in 2022, to be honest, if any steps were taken.”

All of the deaths reviewed by NBC News happened outside the U.S., where regulations regarding carbon monoxide detectors are inconsistent(48 U.S. states have laws mandating the installation of carbon monoxide detectors in at least some residential buildings, according to First Alert, a company that specializes in fire and carbon monoxide safety). Four of the cases reviewed by NBC News happened in Mexico. The other cases happened in Brazil, Colombia, Chile, China and Taiwan.

Airbnb’s international footprint amid the patchwork of carbon monoxide regulation presents an already-challenging compliance landscape for the company, which says it’s advocated for carbon monoxide detector regulation in Mexico and other countries. But family members say the wide variability of regulation is even more reason for Airbnb to step in and set its own standard on carbon monoxide detectors.

A life cut short

Jaime Mejia jumped on a flight to Brazil with little information other than a message from an Airbnb host telling him that his son had died.

Sebastian Mejia, 24, had moved from Miami to Rio de Janeiro in October 2022 on a Fulbright scholarship to study Indigenous communities. His budget was tight, but he found an affordable Airbnb. He called his family every week to check in, and they were proud of how far his hard work had taken him.

On Oct. 5, 2022, Sebastian was found dead in the shower of his Airbnb. A water heater in the bathroom had been leaking carbon monoxide, according to a technical report from Rio de Janeiro police, and the apartment had no detector to warn him. Carbon monoxide levels measured in the apartment were four times the maximum acceptable levels, police said.

Sebastian’s family believes that if the company required property owners to install carbon monoxide detectors, he might still be alive.

Sebastian Mejia.Courtesy Mejia family

“This shouldn’t have happened. It was easily preventable,” Sebastian’s brother, Daniel, said. “It should be something that’s the most basic thing that you should be able to go take a shower and not die.”

After Sebastian’s death, it took 10 days to go through the repatriation process and return his body to the United States. Over 300 people from across the U.S. traveled to Florida to attend his funeral.

Sebastian’s family said that Airbnb never reached out to them after Sebastian’s death. In June, they sued the company in California state court. An Airbnb representative said that communication from the company was directed to the family’s legal representative.

“Unfortunately he has not been the first and he will not be the last, and other families have to go through the same experience,” his mother, Rosa Elena Martinez, said. “And that’s terrible that Airbnb, knowing exactly what’s happening, they haven’t done anything to stop it.”

Martinez said their primary motivation for bringing the lawsuit was to inspire a policy change at the company.

“They could pay us $1. But if they change the policy, and we make these public, it will be totally worth it,” she said. In court, Martinez is seeking damages exceeding $25,000, according to the complaint, and a legal injunction that would force Airbnb to remove listings without carbon monoxide detectors and mandate the use of detectors along with the inspection of fuel-burning devices. No trial date has been set.

Sebastian’s family isn’t alone in their pursuit. NBC News identified six lawsuits pertaining to carbon monoxide poisoning at Airbnbs. Three are ongoing, two were settled and one was dismissed.

Jaime Mejia holds a photo of him and his children, including Sebastian, standing behind the couch. Saul Martinez for NBC News

Lawyers and families say that in their disputes with the company, Airbnb has attempted to push them into private arbitration. Users consent to private arbitration when they sign up as part of the platform’s terms of service. The private arbitration system used by many corporations has been criticized as favoring businesses in disputes.An Airbnb representative said that arbitration is typically faster and more cost-effective in resolving disputes for all parties.

A persistent killer

Carbon monoxide is an invisible killer: a colorless, odorless gas that can be fatal depending on the exposure levels. Poisoning symptoms mimic the flu, according to the Centers for Disease Control and Prevention, which makes poisoning hard to detect until it’s too late.

Deaths from carbon monoxide poisoning increased every year from 2012 to 2019, according to a report by the U.S. Consumer Product Safety Commission on consumer product-related carbon monoxide deaths. In 2020, Congress passed a bill to require carbon monoxide detectors in public housing, after an NBC News investigation uncovered at least 13 deaths of public housing residents from carbon monoxide poisoning since 2003.

Globally, carbon monoxide poisoning remains an issue, with 28,900 deaths recorded in 2021, according to research published in the medical journal The Lancet, most of which the study noted were preventable.

“Out-of-date, ill-maintained, or incorrectly installed heating systems have been linked to many cases of residential unintentional carbon monoxide poisoning,” the study said.

In recent years, carbon monoxide deaths have also occurred at hotels and other short-term rentals.

Airbnb has taken some steps to address carbon monoxide concerns, primarily by encouraging hosts to install detectors. In 2014, it began offering one free carbon monoxide detector to hosts; Airbnb will not distribute multiple detectors to a single host, despite the prevalence of multi-unit Airbnb businesses. The International Association of Fire Chiefs recommends a carbon monoxide detector be placed on every floor of a residence. Airbnb’s program has been running for nine years, but in June the company said it had only distributed enough detectors to cover 2.3% of its 7 million active listings. The company said in a statement to NBC News that it had distributed detectors to 230,000 hosts out of over 4 million, or around 5.8%.

Airbnb listings display if rental properties do or don’t have carbon monoxide detectors. A listing that lacks detectors displays crossed-out text that says “Carbon monoxide alarm” at the bottom of the “What this place offers” section, among other features like “Kitchen,” “Wifi” and “TV.”

Airbnb displays the lack of a carbon monoxide or smoke detector in the amenities section of listings.

Airbnb says that it flags if listings don’t have carbon monoxide detectors to guests in confirmation and reminder emails.

A 2018 study in the journal Injury Prevention found that only 57.5% of U.S.-based Airbnb locations were listed as having carbon monoxide detectors.

Charon McNabb, founder of the National Carbon Monoxide Awareness Association (NCOAA), noted that Airbnb has taken other sweeping actions affecting all of its listings previously, questioning why it wouldn’t do the same for carbon monoxide.

“Airbnb implemented mandatory Covid-19 protocols to save lives. Implementing the same type of safety measures with carbon monoxide alarms would also save lives,” McNabb said. “Recommendations are not enough and carbon monoxide alarms should be mandated in all hotels and Airbnbs.”

Poisonings and deaths can still occur, though, even if detectors are installed. In one 2022 case, three Americans reportedly died of carbon monoxide poisoning in an Airbnb rental that was advertised as having carbon monoxide detectors inside. It’s not clear whether or not they were functioning.

According to the NCOAA, 565 were victims of carbon monoxide poisoning in the U.S. this year. And the CDC estimates that over 400 Americans die annually from carbon monoxide poisoning, which McNabb said only represents known cases.

Elena Martinez and Jaime Mejia in front of a columbarium memorial where their son’s ashes are interred in Naples, Fla.Saul Martinez for NBC News

“We know that that number is far too low,” McNabb said. “There are many, many more carbon monoxide poisoning deaths and injuries that are not included in that number due to the nature of the poisoning.”

Andrea Vastis, senior director of public education at the National Fire Protection Association, said states ought to have codes and laws that compel companies such as Airbnb and VRBO to install carbon monoxide alarms.

“Peer-to-peer rentals are another place where there is a lag in terms of statewide regulations and laws enacted for what has to be safety equipment involved,” she said.

VRBO did not respond to a request for comment.

Many people don’t consider that their vacation destination may not have the same rules around safety equipment as their home city or state, or that homes rented on sites like Airbnb could be regulated differently than hotels. Given the patchwork of regulation and the slow pace of legal change, victims’ families questioned why Airbnb wouldn’t step in to require carbon monoxide detectors.

Alarms are necessary, experts say, because it can be incredibly hard to realize you are being affected by carbon monoxide before it is too late.

“Because of the sinister nature of carbon monoxide poisoning, it’s not always easy to identify the health effects that we’re feeling, especially when we’re on vacation,” McNabb said.

McNabb recommended travelers carry portable carbon monoxide detectors, which retail as low as $10.

Still, McNabb said that she believes most people operate with the expectation that there is a certain level of safety when they rent a hotel room or an Airbnb.

“We’re not taking our own water test kit to an Airbnb or hotel, that is the minimum level that we expect when we rent a hospitality suite,” she said. “When we go to bed at night we expect there to be a lock on the door. We expect that when we go to bed, we’re going to wake up in the morning and not have to worry about carbon monoxide threatening our vacation or our lives.”

Ben Goggin is the deputy editor for technology at NBC News Digital.

Khadijah Khogeer

Khadijah Khogeer is an intern on NBC News' tech desk.