Congress approved legislation Friday to strengthen security for the nation's airports and airlines. It now will be passed to President Bush, who is expected to sign it in a ceremony at Reagan National Airport Monday morning.

The compromise bill passed the House by a 410-9 vote just hours after it was endorsed by the Senate on a voice vote.

"This is a historic moment," said the House Transportation Committee chairman, Rep. Don Young, R-Alaska. He called the package "the best security bill this nation has every had for the flying public."

Bush plans to sign the bill Monday. The completed bill comes just days before the Thanksgiving holiday, and lawmakers were determined to send a positive message to Americans.

"As families prepare for the biggest travel day in the nation they can feel assured that airport security will be strengthened nationwide the very moment the president signs this landmark legislation into law," said Sen. Max Cleland, D-Ga.

In addition to increasing the number of federal air marshals on planes, the deal scraps the system of having private companies check passengers and bags. Instead, airport screeners will become federal employees. After three years, airports will have the option of choosing between federal employees and private screeners.

Even Tom DeLay, R-Texas, the most vocal opponent of federalizing the screener workforce, is said to be pleased with the deal.

The compromise prohibits strikes and allows for dismissal of those who don't do their jobs right.

The bill also calls for all checked bags to be screened and requires improved screening technology, including bomb detectors.

The seed for a breakthrough came Wednesday when both sides suggested that airports have a say in what capacity they want screeners to function. Senate bill supporters suggested airports may be given an "opt-out" system in which they could choose private workers if their performance is up to par with federal security standards.

Backers of the House bill offered an "opt-in" provision that allows airports to ask for federal staff if it feels federal workers could provide better security.

The compromise would also create five categories of airports. One airport in each category could opt out immediately as part of a pilot program to measure new federal standards without federalizing employees. After three years, five airports in each category can opt out if they choose to sue law enforcement or private contractors.

Federalizing the screeners will put 28,000 new employees on the federal payroll, something agreed to in the Senate bill but opposed by the House.

GOP leaders said they are taking the plan to caucus to get it ratified by Republican members. A vote is expected Friday and the bill could be on the president's desk for his signature before Thanksgiving.

On other measures, the two bills both require airlines to fortify cockpit doors, increase air marshals on flights and move toward screening of all check-in bags. A fee of $2.50 per leg of flight would be levied to pay for the increased security. The fee, however, cannot exceed $5 per trip.

The bill would also put transportation security under the jurisdiction of the Transportation Department as stated in the House bill. The Senate bill wanted security under the Justice Department.

The compromise also keeps most of the House liability protections for the owners of the World Trade Center and others affected by the Sept. 11 attacks.

On Wednesday, Senate Governmental Affairs Committee chairman Joe Lieberman, D-Conn., urged Congress to get a bill to the president's desk. He was responding to witnesses who testified that there are "still alarming lapses of security" at the airports despite efforts to beef up security.

According to Transportation Department Inspector General Kenneth Mead, fewer than 10 percent of checked bags are inspected for bombs and the overworked inspectors are starting to slip in their duties.

Last weekend, a survey by his office of 30 machines at nine airports found that 73 percent were not in continuous use. Over the last several weeks, 90 security problems have been cited at random checks of airports, including the latest incident where a Chinese chef tried to board a flight to Hong Kong with two large cutting knives in his baggage.

"You know something is wrong when screeners are confiscating thousands of nail clippers but allowing people with arsenals of weapons through," said Sen. Dick Durbin, D-Ill.

Mead listed several measures that have been taken since Sept. 11 to bolster security, including reinforced cockpit doors, use of law enforcement officials and the National Guard at airport checkpoints, background checks of airport personnel, use of FBI watch lists to identify suspicious passengers, and allowing only ticketed passengers beyond screening points.

The Associated Press contributed to this report.