“Firefighters have evolved — but residential safety equipment hadn't.”

Detection of smoke and carbon monoxide is particularly vital because smoke is more dangerous than ever. Modern households are filled with more synthetic materials made from oil and its derivatives — such as polyurethane and reconstituted soda bottles — so smoke is often tainted with toxins such as hydrogen cyanide, phosgene and carbon monoxide. In fact, according to the NFPA, most fatalities from fires are caused by smoke inhalation, not by burns. Ware’s experience was typical of a modern residential fire: “[The sunroom] was full of smoke from the ceiling to the bottom of the floor,” she says.

Because of the changes to residential fires in recent years, firefighters have had to adapt their tactics. This has meant wearing advanced protective gear and getting to fires faster. “It used to be that the rule was a fire in a home would double its size every two minutes,” says Bryant. “Because of the new materials, that’s a lot quicker now. That’s why those response times are so critical.”

Once firefighters arrive, they must attack the fires more efficiently than they have in the past. “The normal procedure, ever since Ben Franklin started fire departments,” says Drengenberg, “was to get up on a roof and chop a hole in it.” Cutting a hole in the roof allows firefighters to vent hazardous chemicals and smoke, as well as see how far a fire has progressed. Today, firefighters are doing things differently. “They’re seeing maybe that isn’t the best way — that it may introduce more oxygen and help it spread quicker,” says Drengenberg, who points out that masks and air packs allow firefighters more versatility than ever before.

Smoke alarms, too, are changing. “As house fires have become more dangerous, firefighters have evolved — but residential fire safety equipment hadn't, and we wanted to change that with Nest Protect,” says Maxime Veron, Nest’s head of hardware product marketing. Because the Ware family had smart alarms, Tina’s husband Doug — who had already left for work — knew about the fire almost instantaneously via his smartphone: “He was already aware of [the fire] before I had even called him,” says Mrs. Ware.