Because many pet doors are the size of a standard sheet of paper or smaller, parents may believe their child is safely contained inside the home. But a typical three-year-old male child weighs only 38 pounds and can easily pass through an opening that size.

One afternoon in August 2006, two-year-old Matthew Ranfone wriggled through a pet door in his Orlando home and made his way to the family’s backyard pool. A few minutes later, his parents found him floating face down. Medical personnel were able to revive the toddler on the way to the hospital, but he died 13 days later from the injuries sustained in the near drowning. (See petaccessdangers.org.)

Accidents involving children escaping through pet doors are more common than one might think, says Sean Kane, president of Safety Research and Strategies, who has been researching the issue nationally. In the past decade, more than 100 children have drowned, nearly drowned, or been injured after leaving the home through a pet door, he says.

Kane identified the incidents through news stories, public health specialists, the Consumer Product Safety Commission, and coroners/medical examiners. “But the total number to date underestimates the true scope of the problem because most accidental drownings are classified only by cause of death or injury and do not identify how the child accessed the water,” he says.

“Child-injury researchers are well aware of the link between pet access doors and child injury and death, but many parents and caregivers do not appreciate the risk associated with use of a pet door, and how young children can drown, become lost, wander into streets, or otherwise become seriously injured or killed after exiting a home through a pet door.” (Read the rest of this post on our Safety blog.)

See our related report on how to childproof your deck, porch, and yard.