Temperatures inside vehicles rise dangerously fast, researcher says

A heatstroke researcheris reminding people just how hot vehicles can get on a summer day and how rapidly those temperatures can become lethal, especially for children.

Jan Null, with the Department of Meteorology and Climate Science at San Jose State University, says the temperature inside a vehicle can hit 50 C and it doesn't take long.

"In the first ten minutes after the doors are shut on a vehicle, even if it's been air-conditioned, the temperature rises about 10 degrees Celsius, " Null said. "So if you take a day of 30 C, that means you are up at close to 40 C in just tenminutes," he said.

On Monday, employees of a Subway restaurant on Notre Dame Avenue in Winnipeg were alarmed to see two young children left unattended in a vehicle. Witnesses said the children were in the vehicle, with the windows rolled down, for more than half an hour.

Police were called and the children were okay.

At the time, the temperature was 29 C, with humidex valuesit felt more like 38.

• Subway restaurant workers find children unattended in hot van

Null said vehicles can get dangerously hot, very quickly. "85 percent of the rise is in the first 30 minutes, which is one of the reasons you know, even a short time in a vehicle can be very hazardous," he said.

Null has conducted research into the environments of vehicles using remote thermometers.

He found cracking a windowdidn't make much of a difference. "I did a couple of days of my testing with the windows cracked and the difference it made was only a degree or two. So not enough certainly that would be a saving temperature difference."

Null is a meteorologist and has been tracking the number of heatstroke deaths of children in vehicles for years. According to his data, the average number of child heatstroke fatalities in the U.S. per year since 1998 is 37.

The Canada Safety Council estimates between four and six children die from being left unattended in vehicles every year in Canada.

Null says for young children, the dangersare great.

"Infants and children, their bodies are less developed and they heat up much faster. Their body temperatures rise three to five times faster than an adult's could."

Null will take his message about the dangers of leaving children in sweltering cars to Washington, D.C. on Friday, as part of National Heatstroke Prevention Day in the U.S.