A 22-year-old Alexandria woman died yesterday, authorities said, a day after a lifeguard pulled her from the bottom of a swimming pool at a high-rise condominium complex in the Holmes Run area of the city.

The woman's death, which police said was an accident, followed a near drowning Wednesday at a public pool in Loudoun County, where an 11-year-old girl rescued an unconscious 6-year-old boy. In both incidents, lifeguards were on duty.

At the Alexandria pool, police said, children saw Anita Osei on the bottom of the pool shortly before 4 p.m. Friday and alerted the lifeguard and other adults. The lifeguard and two residents pulled Osei out and performed CPR until rescue workers arrived and took her to Inova Alexandria Hospital, police said.

Osei was pronounced dead at 8:44 a.m. yesterday. There was no indication of foul play, and authorities are investigating the death as an accident, police said. The lifeguard's name was not released. Osei Antwi, 29, a friend of Osei, said yesterday, "I don't think she knew how to swim."

Police said Osei lived at the 36-year-old condominium complex called Pavilion on the Park, a 16-story complex with about 280 units in the 5300 block of Holmes Run Parkway. Several residents said Osei was visiting. The condominium management and Osei's mother, who lives in Alexandria, declined to comment.

In the Loudoun accident at the Algonkian Regional Park pool, a lifeguard told Northern Virginia Regional Park Authority officials that she saw the 6-year-old boy at the bottom of the pool before 11-year-old Elizabeth Dapper rescued him. The lifeguard said she rushed over, took the boy from Elizabeth and revived him.

Park officials said the lifeguard followed the correct procedure and would have saved the boy even if Elizabeth had not retrieved him.

In contrast to many places nationwide, jurisdictions in the Washington area require that public or semi-public pools employ at least one lifeguard, said B.J. Fisher of the American Lifeguard Association, a national certification agency.

However, Fisher, who is health and safety director at the association, questioned whether the local codes go far enough. For instance, he said, the rules require that only one lifeguard be on duty while the pool is open. But "for a lot of rescue scenarios, you need two lifeguards -- one to initiate the save, another to call 911," he said yesterday.

Fisher was also concerned that, with the exception of Fairfax County, local jurisdictions and the District permit pool owners to assign lifeguards additional duties -- such as cleaning the bathhouse or manning sign-in sheets -- that prevent them from watching the pool and enforcing safety rules at all times.

"Most drownings are quiet. When a person goes under the water, if the lifeguard isn't watching attentively, the time clock starts right away. . . . In two to three minutes, the heart stops and then goes into cardiac arrest," Fisher said.

Alexandria and Arlington County considered but ultimately rejected a prohibition on assigning extra work to lifeguards several years ago when Fairfax passed its ban, Fisher said.

Fisher said there are many reasons an adult may drown in a pool. "It could be someone who has an allergic reaction or a seizure for the first time in his life, or a novice swimmer who gets a cramp and panics. . . . Just because they are an adult doesn't mean they aren't going to get into as much trouble as a child," he said.