A child dies every five days in a portable pool during warm-weather months, according to the first U.S. study on child drownings in portable pools.

The study, published in the journal “Pediatrics,” shows 209 deaths and 35 near-drownings of children younger than 12 from 2001 to 2009 in portable pools, including small wading pools less than 18 inches deep, inflatable pools and other soft-sided pools that reach depths of up to 4 feet.

It doesn’t take much water for a small child to get in trouble, according to Jessica Saunders, community relations manager at Children’s Medical Center of Dayton.

“A child can drown in less than 1 inch of water,” she said.

The study found that in drowning and near-drowning cases, less than half — only 43 percent — of children were supervised by adults.

“Any time you’ve got a small child, you need to know where they are and what they’re doing 100 percent of the time,” said Lisa Schwing, trauma program manager at Dayton Children’s.

Especially at the backyard pool, where there are lots of distractions, Schwing said there’s a difference between just being present to supervise and actively watching the kids.

“That doesn’t mean reading a book, talking on a cell phone or cooking on the grill,” she said.

According to Schwing, it doesn’t take long for a pool mishap to become life-threatening.

“It’s a matter of minutes before there’s no second chance,” she said.

Kids who survive a near-drowning may have brain damage, and after four to six minutes underwater, that damage is usually irreversible, according to Dayton Children’s.

The Pediatric Trauma and Emergency Center at Dayton Children’s dealt with 13 near-drowning incidents in 2010. So far the number of cases for 2011 is at least 10, according to Schwing.

Most children who drowned were under the age of 5 and CPR was administered before emergency crews arrived in only 15 percent of drowning fatalities and 17 percent of near-drownings, according to the study.

Saunders recommends anyone in charge of caring for kids be trained in CPR.

“You might never use it, but the one time you have to, it’s a life-or- death situation,” she said.

“Change a life starting with your own,” said Soteria Brown, marketing and communication specialist with the Dayton Area Chapter Red Cross. “You can be the right person that’s there at the right place, at the right time.”

The Dayton Area Chapter Red Cross offers a variety of first-aid classes and training. You can register online at www.dac.redcross.org or by calling (937) 222-6711.

Contact this reporter at (937) 225-2002 or ksteele@DaytonDaily News.com.