NEW YORK - Hotel housekeepers say they often feel a twinge of fear when they slide the key card, turn the door handle, and step into a room to clean it. What will they find?

For Argelia Rico, it was a nude man touching himself as he ogled her. For Kimberly Phillips, it was a pair of dogs that tore into her leg.

Last week, the former head of the International Monetary Fund, Dominique Strauss-Kahn, was charged with chasing a housekeeper around his $3,000-a-night penthouse suite and forcing her to perform oral sex at the Sofitel New York Hotel.

Labor groups and hotel housekeepers have reported at least 10 other attacks in the United States in recent years, from the Washington suburb of Gaithersburg, Md., to Grand Island, Neb.

Labor groups say many more are hushed up because the victims are illegal immigrants or because hotels are wary of scaring off guests. Many hotels laid off security staff during the recession, leaving workers even more vulnerable, they said.

"It's dangerous work," said Yazmin Vazquez, who works at a hotel in downtown Chicago. "These customers think they can use us for anything they want because we don't have the power that they have or the money that they have."

Anthony Roman, a consultant on Long Island who worked for 30 years in security for hotels, said he saw dozens of incidents involving female room attendants, from drunken propositions to rape.

"They're not an infrequent occurrence," he said.

Roman said that although hotels try to make sure housekeepers aren't alone for their whole shifts, "if you have a sexual predator by nature, all bets are off."

At the luxury hotel in Toronto where Andria Babbington worked for 17 years, housekeepers especially hated doing "turndown" service, preparing beds for the night.

Some men would put money on the pillow, ask for sexual favors, and tell the women they could take the money when they left, Babbington said.

Others took a more circuitous route: They would inquire about a housekeeper's home country and how many relatives they were supporting. Then came some sympathetic-sounding questions about how much the hotel paid them - followed by an offer of money for sex.

One guest bugged Babbington for days about having a threesome with his wife. She hid her name tag whenever she cleaned his room. If a housekeeper reacted angrily, the guest would find some reason to complain, she said.

"When they complained, the management would send a fruit basket up to their room and offer them a discount on their next stay," Babbington, 45, said. "It became the norm, and we couldn't do anything about it."

Now a union organizer, Babbington said she hears similar stories from workers at other hotels.

Rico, 38, a housekeeper at a hotel in Irvine, Calif., said she was cleaning a bathroom in 2009 when a guest entered and asked her to change his sheets. She did, then went to get her cleaning supplies out of the bathroom.

When she came out, he was lying nude on the bed, watching her and touching himself, she said.

"When I told my supervisors, they didn't do anything," Rico said. "From then on, I had to ask a coworker from the floor upstairs to accompany me so I could clean his room, because that really scared me."

Phillips was cleaning rooms at a Hampton Inn in Lebanon, Ky., last year when she opened the door of Room 118 to find two dogs. The animals attacked, biting her left leg to the bone, until a hotel guest fought them off with Phillips' broom.

The dogs belonged to a contractor staying at the hotel while doing work there.

Phillips, 40, now uses a cane and walks with a limp. She has nerve damage in her leg and suffers from panic attacks.

Many hotels have adopted policies aimed at protecting housekeepers, such as barring them from cleaning rooms while the occupants are present. One standard practice is to prop the door open with a supply cart.

Vazquez, 40, says she started wearing extra clothes under her uniform as an added layer of protection after a VIP guest barged into a bathroom she was cleaning and pulled out his private parts in August. She also wears a jacket that comes down to her thighs.

"Anything to hide your figure," she said.

Labor groups worry that the recession has created more danger by forcing hotels to cut back on security guards and housekeepers.

"You're on a floor by yourself, with those long hallways and nobody around, cleaning 30 rooms a day alone," said Tho Do, a vice president of Unite Here, a union that represents hotel workers. "You don't have a lot of protection."