HOUSTON -

Texas led the nation in the number of children who died as a result of being left alone in a hot car in 2011.

The sad thing is these cases are completely preventable.

A 7-month-old Sugar Land boy died after his father left him in the back seat of his truck. That day in May, the temperatures only reached 89 degrees.

Estella Olguin with Child Protective Services said, "Sometimes when we go to work, we go into autopilot. You don't even know how you made it into work. You just did, so it's easy to overlook a sleeping infant."

The Houston Fire Department has teamed up with State Farm Insurance to launch a new safety campaign called "Look Before You Lock."

Drivers will start noticing billboards around the city reminding caregivers to never forget a child in a car.

Houston Fire Chief Terry Garrison said, "More than 50 percent of these children were just forgotten by their caregiver. This is why we're absolutely stressing 'Look Before You Lock.'"

Even on a mild day with the windows cracked, the interior of a car can heat up to 120 degrees.

Public Safety Committee Chair Ed Gonzalez said, "The clock is ticking in a very hot vehicle, so time is of the essence."

Children are far more sensitive to heat.

Dr. David Persse with the city of Houston Health Authority explained, "When the body temperature rises above 107 degrees, that's when we believe the brain cells begin to die, and that can happen very rapidly in a car. You need to think of (it) as an oven in the hot sun in Texas with no air conditioning going on."

While many of these incidents of hyperthermia are accidental, there are cases where kids are left in cars while a parent or sitter runs an errand.

Houston Police Chief Charles McClelland said, "It's actually a class C misdemeanor if you leave a child in a vehicle, even if nothing's going on. If that child is under the age of 7, even if the window is down on that vehicle, you can be cited."

McClelland added that charges can also include child endangerment, child abandonment, injury to a child or worse.

While it's usually cases of kids dying in hot cars that make the news, every day calls come into CPS about kids being left alone in cars. Children have become victims of carjackings, they've put cars into gear and even been strangled while playing with car windows and doors.

One idea to help you remember to "Look Before You Lock" is to leave your purse, briefcase or lunch in the back seat.

You can also set your cellphone alarm to reminder you once you get to work that you dropped the child off.

Also, have the day care or school call you immediately if the child has not arrived for the day.