The number of non-fatal injuries resulting from hot tub use has increased in the U.S., according to a new study.

Researchers who analyzed emergency room records found that the number of non-fatal injuries related to hot tub, whirlpool and spa use increased by 160 per cent, from about 2,500 in 1990 to more than 6,600 in 2007.

"While the majority of injuries occurred among patients older than 16, children are still at high risk for hot tub-related injuries," said study author Lara McKenzie in a news release.

McKenzie is the principal investigator at the Center for Injury Research and Policy at Nationwide Children's Hospital in Columbus, Ohio.

"Due to the differing mechanisms of injury and the potential severity of these injuries, the pediatric population deserves special attention," McKenzie said.

Slips and falls accounted for about half of the injuries, the team reported in the American Journal of Preventive Medicine.

Children younger than six were most likely to experience near-drowning.

Other common injuries were lacerations, mainly to the lower extremities and head.

The researchers encouraged people to take precautions such as:

• Put slip-resistant surfaces in and around the hot tub.
• Limit time and temperature of hot tub exposure to 10 to 15 minutes at no more than 40 C.
• Keep hot tubs covered and locked when not in use.
• Consider installing a fence or barrier around the area.
• Set rules prohibiting jumping and diving for children.

Suction drains have also caused injuries among children.