Of all the wildfires that ravaged California in 2018, the Camp Fire was the deadliest. It tore through the mountain town of Paradise and killed at least 85 people, destroying the local Feather River Hospital along the way—so just as emergency services were trying to evacuate and tend to the injured, they also had to transport admitted patients.

That moment made real a problem that specialists had been warning about for years. “There were four beds immediately available in the entirety of Northern California for a burn patient. Everyone else was going to have to wing it,” says Tina Palmieri, director of the Firefighters Burn Center at UC Davis, which would receive 10 burn victims from the Camp Fire alone. (Triage and emergency planning allowed for a kind of rejiggering that can add a few beds.) Technically, those four slots in the hospital—attended by teams trained to triage and treat burns—were among just 53 available in all of California.

Across the western United States, wildfires are getting worse—because of climate change-induced heat and drought as well as the encroachment of human beings into what was once wilderness. The so-called wildland-urban interface gets bigger as development sprawls outward, and the WUI is where destructive wildfires often start. Fire season is forever on the Burning Earth.

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That means charred landscape, destroyed buildings, lost homes, death. Not many medical caregivers are ready to deal with all that. Corporate medical systems keep hospitals full or nearly full all the time—which means they don’t keep beds open for the mere possibility of burn patients, and they don’t keep the gear on hand to treat them. Doctors and nurses no longer receive much training in treating burns, if they get any. “There are a lot of trauma surgeons, a lot of trauma nurses, a lot of emergency department doctors. There are a lot of prehospital people,” says James Jeng, a burn surgeon at Mt. Sinai Hospital. “But the burn cognoscenti, it’s a small village of mad monks. There are maybe 300 burn surgeons in the US, and maybe 300 burn nurses.”

So you can see the problem here. Increasing wildfires could mean an increase in serious burn injuries, potentially even mass-casualty burn incidents with dozens or hundreds of victims. In the 20th century, those were rare; the lesson of the 73 major burn incidents across those 100 years is that most people either die or walk away—but those who survive with severe burns are resource-intensive and challenging to treat. The lesson of 21st-century fire disasters is that they’re increasing around the world, and that they tend to be worse than what the local infrastructure can handle. And if any of last year’s fires had a lot of burn survivors? “It would only take a few,” says Colleen Ryan, a surgeon at Massachusetts General Hospital and chair of the American Burn Association’s Committee on Organization and Delivery of Burn Care. “Northern California was one house fire away from being completely full.”

Burns and smoke are what kill fire victims. The 25 deaths in the Oakland hills fire of 1991, for example, were all related to major burns (and possibly smoke inhalation; it’s difficult to disentangle the two after death). They were people trapped by the fire. Six people made it to hospitals and survived their burn injuries. But in 1991, three of the nine regional hospitals that received casualties from the fire had dedicated inpatient burn units. Two of those hospitals no longer do, and the third has closed entirely. The US has something like 1,800 dedicated burn beds. That’s it.

The rules for triaging burn victims in a mass casualty situation—for determining how to use finite resources to do the most good for the most people—are grim but simple. Depending on whether you are a glass-half-full or glass-half-empty sort of person, you could call them either “survival tables” or “death tables.” They’re charts, based on two pieces of data, or three if you’re fancy: the victim’s age, the percent of their body burned, and maybe smoke inhalation. Hit too high a number on those metrics during a disaster—when everyone gets an altered standard of care—and you’re likely to receive only comfort, not life-saving treatment. Triage is a cold equation.