NEW ORLEANS - The Gulf of Mexico oil spill has brought out thousands of people who just want to help - though there isn't much for them to do unless they own a Hazmat suit.

Directors of charities and BP P.L.C. say the outpouring has been huge among people with vivid memories of Hurricane Katrina five years ago.

But cleaning oiled birds and tar-stained beaches isn't as straightforward as clearing rubble. In many cases, finding enough work for all the volunteers has been difficult.

"Katrina needed everybody and anybody that could help," said Jim Kelly, co-president and CEO of Catholic Charities. "But this isn't a case of hitting the ground and helping to gut a house or rebuild it. The needs here are specialized in many ways."

BP has said it will use only trained workers and professionals to clean up the oil and to wash oiled wildlife, adding to deepening frustration over the government's and BP's responses to the spill. The workers also need special safety equipment, BP spokesman Mark Proegler said.

He suggested volunteers could visit BP's websites and sign on with subcontractors working along the coast. But Bethany Kraft of the Alabama Coastal Foundation said by e-mail that many people were not looking for full-time work. And there is no guarantee they would be hired, because some states require that those hired be unemployed or otherwise affected by the spill, she said.

While foremen must take a full 40-hour hazardous-materials course, most workers need only an abbreviated four-hour course, Kraft said. However, the need for such training - which so far hasn't been opened to the public by BP - may be overstated.

"All the Hazmat training does is basically tell people common-sense things, like, 'Don't eat it,' " said Edward B. Overton of the Louisiana State School of Coast and Environment.

In Louisiana, many rushed to help after Katrina in 2005 upon seeing the horrifying scenes of bodies floating in floodwaters and people stranded on roofs. This time, the heart-rending pictures of oil-covered pelicans, dead sea turtles stacked on beaches, and idled fishermen suddenly without incomes have sparked another outpouring of offers.

More than 15,000 people from across the country have signed up on BP's web site, Proegler said. Others are volunteering through charitable organizations, environmental groups, and state agencies.

"I grew up in New Orleans and went through Katrina," said Barbara Siefken, an unemployed lawyer. She interrupts her job search twice a week to drive two hours to and from St. Patrick's Catholic Church in Port Sulpher to hand out food vouchers and baby supplies, or help fishermen sign up for services offered by the state or charities.

"I know what volunteers did for us," she said. "I just wanted to give some of that back."

There are other ways to help. About 10,000 volunteers without biohazard training have registered with the Coalition to Restore Coastal Louisiana, said executive director Steven Peyronnin. Hundreds of them have been sent to clear beaches of debris before oil hits, he said.

"It will help when the oil comes ashore," he said. "It will make that job easier."

In Florida, about one-third of the 7,683 people who offered to help have actually worked, mostly in pre-oil beach cleanup, said Wendy Spencer, chief executive officer of the Governor's Commission on Volunteerism.

In Alabama, 5,000 people signed up for the first week of a training program designed by Mobile Baykeeper and Alabama Coastal Foundation, said Casi Callaway, executive director of Mobile Baykeeper. The program trains volunteers to photograph and document what's happening along the state's shoreline.