A destroyed car sits in the remains of a home in Santa Rosa, Calif., on Oct. 9. (John G. Mabanglo/European Pressphoto Agency/EFE/REX/Shutterstock)

The wildfires racing through Northern California have killed 31 people so far and forced thousands to evacuate their homes.

They also have forced fire officials and residents to confront fateful decisions: When should you evacuate, and what should you do if you become trapped in a vehicle while trying to get away? Should you stay with the vehicle as flames are closing in or try to leave the vehicle to find safety somewhere nearby?

It turns out that not only are there are few options in this predicament, but there’s not a whole lot of research on the issue, either. Yet vehicles are where many people in previous fires have perished, such as the June forest fire that killed 64 people in Portugal, including 47 people who died in their vehicles on a road while trying to flee. An investigation into the calamity found the authorities had failed to evacuate villages in time.

J. Keith Gilless, dean of the College of Natural Resources at the University of California at Berkeley and an expert on wildfires, said becoming trapped in a vehicle is one of the leading causes of wildfire deaths because people wait too long to go. He added the most important factor in survival is to heed evacuation warnings and leave early enough that you don’t have to debate whether to seek shelter in a culvert or to take your chances in a car.

“When you’re told to evacuate — go. Don’t consider whether to stay, don’t evaluate it, don’t talk about it with neighbors,” Gilless said. “Go.”

People who wait too long, thinking their vehicle will move faster than the fastest moving fire, don’t realize that wildfires tend to leapfrog and hopscotch across the ground, suddenly blocking highways and streets that were passable a short time before, he said. What’s more, the driving conditions are often difficult, with poor visibility and traffic caused by other people who didn’t flee until the last minute.

In the 1991 Oakland-Berkeley Hills fire, which claimed 25 lives, several people died when their vehicles became blocked by debris or other vehicles that had caught fire, exploded and tumbled onto the street below, according to the Los Angeles Times.

The greatest danger in brush and grass fires isn’t the flames but their radiant heat, and vehicles offer little protection from that. The Federal Emergency Management Agency (FEMA) says researchers are still trying to determine the best advice for last-resort actions. But authorities in California and Australia, where brush fires are common, say experience has taught that it’s generally best to stay calm and stay with the vehicle if other shelter can’t be found.

“The number one thing is to stay calm, especially if you’re driving your vehicle,” said Daniel Berlant, assistant deputy director of the California Department of Forestry and Fire Protection, known as Cal Fire. “Many people get out of their cars, especially at the last moment, because of the movies [where] the car always explodes. The car always flies into the air. That isn’t really reality.”

If you do find yourself faced with a brush or wildfire, here are some survival tips, as drawn from Cal Fire, FEMA and other authorities:

• Take drinking water along with your ID, phone and medications.
• Take a wool blanket or other garment if you have it. Wool is preferable because it doesn’t ignite as easily as other fabrics, especially synthetic ones.
• Have a backup route in mind in case the main evacuation route becomes blocked. If you see smoke, turn around and head away from it.
• Roll up your windows, turn on the AC to recirculate, and close or block air vents when trying to evacuate from a fire, as the smoke can irritate the eyes and respiratory system. Drive slowly with headlights and hazard lights on.
• Cover your face and any other exposed skin with dry fabric, too. Wetting the fabrics is not a good idea, because the intense heat will create steam. If you don’t have a blanket or a garment and you’re caught outside the vehicle, cover yourself with dirt.
• If you see flames approaching your vehicle, try to park where there is no debris, brush, trees or other fuel for the flames, such as a clearing, rocky area, parking lot or just the roadway. If possible, try to put an obstacle between you and the flames: a concrete wall or other solid object.
• Leave the engine running and try to get as low in the car as possible but especially below the windows, to shield yourself from the radiant heat as the flames approach.
• Try to remain calm, and do not exit until the wall of fire has passed.

“You don’t want to open the door and get out and panic at the very last minute as the fire is approaching, because you’re not going to be able to outrun a fire,” Berlant said. “The car is likely to catch on fire, but it’s not going to explode. But what you want to do is — you’re waiting for the flaming fire front to come and pass.”

But, of course, all of these are last-resort measures. As always, the best advice is to get out early. Gilles said: “The real objective here is to not put yourself in a situation [where] you’re thinking, ‘Should I go in the culvert? Should I go in the swimming pool?’ Because the radiant heat off of these really big fires is tremendous.”

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