Nineteen children have died after being left in hot cars this year, according to the National Highway Traffic Safety Administration. On Saturday, an 11-month-old infant died in a suburb of Chattanooga, Tenn., after being left in a car. A memorial was erected in the parking lot where Chattanooga police say the baby was discovered. Both parents have been charged in the child’s death. (Robin Rudd/Chattanooga Times Free Press via AP)

The federal government’s top road safety agency marked a disturbing milestone this week.

The National Highway Traffic Safety Administration said 19 children have died this year in the United States after being left in hot cars.

The latest case appears to involve an 11-month-old infant who died in a suburb of Chattanooga, Tenn., after the infant’s father left him in the car for an unspecified amount of time, local media reported.

At least two children die per week in hot vehicles on average during the summer months, the National Safety Council says.

The process can be swift: In less than an hour, the temperature in a closed vehicle can climb to dangerous levels when it’s no hotter than 70 degrees outside. Young children and infants are especially vulnerable to hyperthermia because the body’s ability to regulate temperature isn’t yet fully developed in children younger than 4.

The majority of children who die of heat-related complications from being inside a hot car were left there by parents who forgot about them. But a startling number — 17 percent — died because they were left in those vehicles intentionally.  Thirty-nine children died of heatstroke after being left in vehicles in 2016, up from 24 in the previous year, NHTSA reported. The agency didn’t say why the increase might have occurred.

Gene Weingarten wrote one of the most disturbing and poignant accounts about the phenomenon for The Washington Post Magazine. His Pulitzer Prize-winning article noted that the incidence of children dying of hyperthermia began to climb in the 1990s when safety experts found that front-seat air bags posed a risk to small children and recommend that parents put their children in the back seat.

NHTSA, the National Safety Council and other organizations have tried to raise awareness of the dangers, with campaigns reminding motorists to “Look Before You Lock.”

Rep. Tim Ryan (D-Ohio) has introduced legislation that would require automakers to equip vehicles with an alarm that would alert the driver if a child is left in the back seat after the car is turned off. The technology is available in some General Motors vehicles. The National Safety Council is also pushing innovations in car seat design that would use wireless technology to remind the driver when a child is in the rear seat after the vehicle has been turned off.

Keep in mind, however, that Weingarten’s article mentioned that people have been pushing for such technology since at least 2008.

Here are some tips to keep children safe:

  • Never leave a child alone in a car, not even for a minute.
  • Make it a habit to check the back seat when you lock your car.
  • Create reminders for yourself. The National Safety Council recommends leaving something in the back seat with the child that you always take with you, such as a mobile phone, a purse or, the agency says, even your left shoe.
  • If you see a child alone in a car, call 911.

–This file has been updated to correct the name and party denomination of Rep. Tim Ryan.

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