Justin Roy Harris has been charged with murder in the death of his son, Cooper, left in a hot car all day while his father was at work.

The death of a Georgia toddler left in the car by his father on a hot day has drawn intense media scrutiny in recent weeks, especially after 33-year-old Justin Ross Harris was charged with murder. But the case also underscores the fact that, whether intentional or not, dozens of children die each year when they are trapped, or left, in an overheated vehicle.

And it’s not just infants. A new lawsuit alleges a defect in some BMW products resulted in the death of a teen who was inadvertently stuck inside her brother’s car outside of her school. According to the non-profit coalition SafeKids.org, a child dies from heatstroke in a vehicle, on average, once every 10 days, making it the number one cause of non-crash, vehicle-related deaths.

Both Congress and federal regulators have attempted to address the problem, but while several automakers have, at various times announced potential technological solutions, none has yet proved effective and gone into production. And aftermarket devices have proved unreliable enough to force the National Highway Traffic Safety Administration to issue a warning to parents two years ago.

“Well, every heat stroke death, every child’s life lost in a hot car is a tragedy,” NHTSA’s Acting Administrator, told NBC News. It is also, he added, a “100 percent avoidable problem.”

The numbers vary slightly each year: 49 in 2010, 44 in 2013. Through the first week of July of this year, the toll was 16, six less than during the same period a year ago. But that is still far too many, experts contend.

(Honda adds another 1 mil vehicles to airbag recall. Click Here for the story.)

14-year-old Graciela Martinez died after being locked inside a 1997 BMW 328i on a hot day.

While prosecutors contend the Georgia case was an instance of premeditated murder, most child heatstroke deaths appear to be accidents.  As NHTSA’s Friedman suggested, parents get busy racing to work and leave the child behind.  They have no backup when it comes time to run errands, so they dash into a store with the car locked and closed and the baby in a safety seat that can save them from a crash – but not from temperatures that can, on a hot day, soar into triple digits in minutes.

“This can and does happen to the most loving, responsible and attentive parents,” said Jannette Fennell, the founder of Kids and Cars, which has been lobbying for changes to laws – and demanding that automakers introduce technology that can prevent deaths from what is medically known as hyperthermia.

(California family sues BMW after 14-year-old dies in locked car. Click Here for the story.)

A recent study conducted for Safe Kids Worldwide found 14% of parents admitting they’ve left a child in the car alone at some point. And 11% acknowledged they’d done so because they forgot the child was in the car. Meanwhile, the online survey found fathers three times more likely to leave a child behind than mothers.

Often, a parent or caregiver may be gone for just minutes, perhaps to run into a convenience store, but “Many people are shocked to learn that the temperature inside of a car can rise up to 20 degrees in 10 minutes and cracking a window doesn’t help,” said Kate Carr, president and CEO of Safe Kids Worldwide.

The industry has been aware of the problem for some time.  At the New York Auto Show, in April 2002, General Motors’ then-Vice Chairman Harry Pearce unveiled a system that, he said, would be able to detect the heartbeat of a child left in a car and then measure the vehicle’s temperature. If it was becoming dangerously hot, it would chirp the horn to alert a parent or passersby.

“We are committed to putting this technology into production,” suggesting it might first show up on a GM minivan or SUV by 2004. Ford was among the other automakers who also expressed interest in developing such a system – but, a decade later, the technology isn’t available on any automobile as a factory standard feature or option.

There are a few aftermarket warning systems, such as the Childminder Smart Clip System, which alerts a parent if they’ve inadvertently wandered away from a child left in a safety seat or, for that matter, in a shopping cart or somewhere else. But federal regulators have questioned their efficacy.

“While we feel these devices are very well-intended, we don’t think they can be used as the only countermeasure to make sure that you don’t forget your child behind in a car,” former NHTSA chief David Strickland cautioned during a media conference call in July 2012.

One problem is that a quarter or more of the hyperthermia deaths occur when children let themselves into a hot vehicle without a parent’s knowledge.

A 2012 omnibus safety bill passed by Congress set aside money to study possible solutions, but progress has been slow, at best. After abandoning the safety system it announced 12 years ago, Alan Adler, a spokesman for General Motors told NBC News he was “unaware of any technology in the works here for monitoring heated car interiors. The technology you reference was discussed more than a decade ago and was not reliable enough to put into production.”

Ironically, some of the technical basics could make it easier to reach out to parents today. Most GM vehicles sold in the U.S. are equipped with the maker’s OnStar system, which already can alert authorities in the event of a crash severe enough to set off a vehicle’s airbags. Conceivably, if a reliable sensing system were in place, it could call for help, or alert parents, to a child locked inside a hot car.

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Ford Motor Co. recently demonstrated one possible solution, dubbed Mobii. It would place several cameras inside a vehicle’s cabin. These could monitor to see if a motorist were growing sleepy while driving, for example, or tell if a thief broke into a car. But it might also use a temperature sensor and motion detector to detect a child at risk of heat stroke, using technology like GM’s OnStar to call for help.

For now, experts suggest parents and caregivers take several steps to keep their kids safe. Kids and Cars’ Fennell recommends putting a child’s toy, like a stuffed animal, on the front seat as a reminder. NHTSA’s Friedman says parents should put something they need, perhaps a cellphone, in the back seat, next to the child. He also tells parents to keep car keys out of reach of their children so they won’t be able to climb into a hot vehicle on their own.

(This story was produced for, and with the assistance of, NBCNews.com.)