The average American house size has more than doubled since the 1950s and a lot of the extra square footage comes from having a second story. If you have a young child, that could be a serious problem.

A new study in the medical journal Pediatrics found that from 1999 to 2008, an estimated 932,000 children under the age of 5 were taken to hospitals for injuries they sustained on a staircase, usually at home. Averaged out, a child is being treated in an emergency room, for a stair-related injury, every 6 minutes.

“What that tells us is that we have much more that we need to do to make the home environment safer for children,” said Dr. Gary A. Smith, lead author of the study and director of the Center for Injury Research and Policy at Nationwide Children’s Hospital in Columbus, Ohio. “Children under 5 spend most of their time in the home, and even the best parent in the world can’t watch their child 100 percent of the time. It just simply isn’t possible.”

Staircases are not usually designed with a child’s safety in mind. Décor and style often take precedence. Two-thirds of homes can’t accommodate a wall-mounted stair gate at the top of the stairs. About one-third can’t accommodate a pressurized gate at the bottom,

The new report is the first nationwide study focused on small children, injuries and staircases.

The latest findings are based on data collected between 1999 and 2008 from hospital emergency rooms across the country. Of the roughly 932,000 children under 5 who were hurt on staircases, babies 12 months or younger were at highest risk, accounting for 32 percent of the injuries. In fact, stairs were the No. 1 cause of injury for 1-year-old children in the United States.

Among stair-injured children 12 months or younger, 25 percent of them were being carried by an adult at the time of the accident. “I knew that this was something that occurred, but I had no idea that it was that common,” Dr. Smith said.

Researchers were unable to determine how many children actually died from falls because the database lacked complete information on fatalities. Data was available for the most common injuries such as sprains, bruises and hematomas. These accounted for 35 percent of the injuries. Lacerations made up 26 percent of the injuries, followed by closed head injuries, at 20 percent.

Dr. Smith said the findings should prompt parents of small children to look closely at their staircases. Many are made with large, decorative banisters that are so thick most adults would not be able to wrap their fingers and thumbs all the way around. “That allows only what’s called a pinch grip,” he said. “You won’t be able to hold on as firmly if you lose your balance. If that’s the case, you need to install a railing that you can wrap your hand all the way around.”

Pressure mounted gates are not a good choice for protecting children from entering the staircase. They loosen over time and should never be used at the top of the stairs. Wall mounted barriers should be used instead.

Unfortunately, many homes are designed in such a way that they cannot accommodate mounted stair gates, or the steps are made with defects that make them uneven, making falls – among children as well as adults – far more likely. New homes, Dr. Smith said,  should be built with stair gates installed as part of the original construction, with ways that they can be detached.

“We live in a world that is designed by adults largely for the convenience of adults,” he said. “Child safety is very often an afterthought.”

Stair safety tips:

To make sure that your stairs are as safe as they can be, here are some tips on stair safety:

- Make sure that stairs have good lighting. Light switches should be accessible at the top   and bottom of the stairs.

- Keep stairs free of clutter and in good repair.

- Install handrails if not already in place. You should be able to grip the handrail fully.

- Use wall mounted stair gates at both the top and the bottom of stairs.

- Stairs should not be slippery. To reduce the risk of slipping on stairs, non-slippery surface on the whole steps or at least on the leading edges is crucial. Such a surface can be made of rubber, or metal or painted with special slip-resistant paint.

- When carrying a child, avoid carrying any other items.

- Small children, especially those learning to crawl, are little escape artists. If your little one is on the second floor – never leave him or her unattended.