WASHINGTON (AP) _ A repair program for Dotline swimming pool ladders is being undertaken because plastic steps on the ladders may break, the Consumer Product Safety Commission announced Tuesday.

About 80,000 Dotline pool ladders made between 1978 and 1982 are involved, the agency said. They are model numbers SPL-4, SBL-4 and SPL-4000. Those numbers are printed on the assembly instructions accompanying the ladders, which are used in home above-ground pools.

There have been nine incidents reported of steps breaking during use, resulting in lacerations and sprains, the commission reported.

Steps in danger of failing may show small, hairline cracks, the agency warned. It said the manufacturer, Mengo Industries Inc., has offered to replace affected steps at no charge.

Consumers should send steps showing cracks, with their name and address, to Mengo Dotline Industries, Inc., 4611 Green Bay Road, Kenosha, Wis., 53141. Those needing more information can contact Mengo Industries at 414-652-3070 or the Safety Commission at 800-638-CPSC.