Brad Fligor is a captain who steers the three-car ferry that plies the narrow channel between Edgartown and Chappaquiddick.

He has never considered himself a national security risk.

But under a new set of little-known Homeland Security regulations passed by Congress, Mr. Fligor has had to go through a rigorous background check to acquire an identification card from the federal government. The card, the size of a credit card, is called a Transportation Worker Identification Credential, or TWIC for short.

Captains and crew working both on the water and shoreside for the Steamship Authority have one.

Likewise for captains and crew who work for Tisbury Towing and Transportation and some employees of R.M. Packer Company who deliver fuel to waterfront locations.

Even charter captains are supposed to have a TWIC card.

“We’ve got so much identification now,” said Everett (Porky) Francis of Edgartown. Mr. Francis is a charter fishing captain. He hasn’t yet gotten his card but he has gone through the first of two steps to obtain one. The cost is $132.50.

Ed Jerome, a retired elementary school principal who works as a charter fishing captain, is in the process of getting one too. “I understand this is a moving target. A lot of captains are getting them. But when the information first came out we weren’t sure who had to get one,” Mr. Jerome said.

Mr. Fligor was the first Chappaquiddick ferry captain to get a card. He traveled to the enrollment office in Carver and filled out paperwork in late August. He was fingerprinted. This requires two visits, so he returned in September to activate his card and pick it up. There are also enrollment offices in Providence and Boston.

Ann Davis, a New England regional public affairs spokesman for the Transportation Security Administration, said anyone working on a vessel regulated by the Maritime Transportation Security Act is required to have a card. That includes all personnel who work on ferries, passenger boats and vessels that transport goods. Vendors, truckers, contractors and anyone who works in marine secured areas is required to have a card. There are some exemptions. The requirement affects all Coast Guard licensed captains. She said Congress directed the federal government to issue a universal biometric (fingerprint scan which includes a federal background check) security credential that could be recognized nationwide. It is estimated that 1.2 million people will be required to have a card.

“We were ready and done by Oct. 15,” said Phil Parent, director of human resources at the Steamship Authority.

Mr. Parent said 240 vessel employees and another 100 dockworkers have TWIC cards. “I even have one,” Mr. Parent said. SSA general manager Wayne Lamson also got one.

“People don’t realize what Homeland Security has done. Everywhere you go there are changes. It is well organized. We have to have drills at the terminal. We are audited by an independent auditor,” said Ralph Packer of Tisbury Towing and R.M. Packer, who has obtained cards for 25 of his employees. Mr. Packer said anyone visiting his marine terminal is required to have a card, or must be accompanied by a person who has one. The federal requirement could affect electricians and plumbers who work at marine facilities around the country.

Last summer, the TSA set up a temporary office in Woods Hole to accommodate Steamship Authority personnel as well as employees with the Woods Hole Oceanographic Institution, the Marine Biological Laboratory and the National Marine Fisheries Service fisheries center.

“We started last spring. We sent people up in batches, carpooling to Carver. Some went to Providence. On Nantucket they set up a satellite office for a couple of weeks at the town’s request,” Mr. Parent said.

Mr. Parent said reaction to the new bureaucratic process has been acceptance. “People realize that they had to get this document to perform their livelihood. It is part of doing business,” he said.

Peter Wells, who owns the Chappaquiddick ferry, said all four of his full-time captains have complied. He said he does not believe that summer deck hands need cards because they do not go into the engine compartment of the ferry.

Martha’s Vineyard Airport manager Sean Flynn said TWIC doesn’t relate to airports; the airport has its own security card system. “We are meeting all of the requirements,” Mr. Flynn said, adding: “I wish they had one single identification system. I think that is the direction they are heading.”

The U.S. Coast Guard is charged with enforcing the TWIC card requirement. Petty Officer Connie Terrell said the Coast Guard is currently performing spot checks at various shoreside facilities.

Mariners are required to have TWIC cards by April 15. The Coast Guard will be making boat inspections to ensure compliance.

Meanwhile, there is a move afoot to exempt fishing guides and charter captains from the requirement. Legislators in Washington filed a bill calling for an exemption for low risk small boat owners back in July, citing economic hardship for the small business operators. The Small Marine Business and Fishing Guide Relief Act, S. 3377, is still in committee.

For more information visit the government Web site: twicprogram.tsa.dhs.gov.