According to experts, each year an average of 37 children die from heat-related deaths after being trapped inside vehicles. In a memorable demonstration, Los Angeles police officers gathered with local representatives and set up two cars – one with the windows closed and one with them cracked – to demonstrate just how fast each car heats up inside that could potentially be fatal to anyone inside.

Already this year, at least 9 children have died after being left alone in a hot car. According to the National Safety Council, these numbers are expected to rise.

Since 1998, it is estimated that at leas 615 heatstroke deaths of children left in vehicles have occurred, according to San Francisco’s State University’s Department of Geosciences. That is an average of 38 deaths per year. More than half of these children are under the age of 2.