STERLING, Va. Air traffic controllers have to hang it up when they turn 56.

Airline pilots have to call it quits when they reach 65.

So do most law enforcement officers.

Commercial bus drivers, though, can stay behind the wheel until they are 70, 75, 80 and even older. And, many of them do just that.

Because federal transportation regulators have not set a maximum age at which bus drivers must retire, many are kept on until they no longer can handle the bus safely, they lose their licenses because of too many traffic violations, or they have a serious accident that puts them out of commission.

This can cause tough challenges and special problems for motorcoach operators who are fearful of age discrimination complaints or civil lawsuits if they let senior drivers go.

Daecher Consulting Group President Matt Daecher says although dealing with situations involving older drivers can be difficult, it can be done.

Speaking at the fifth annual United Motorcoach Association Safety Management Seminar, the safety specialist said the key is writing a company policy that addresses older driver concerns, but is enforced among all drivers.

"You have to treat everyone alike," he emphasized.

Daecher suggested that a workable policy could single out drivers who have too many near accidents, medical problems that affect their driving skills, or who shy away from nighttime driving or difficult runs.

While those issues might apply mostly to older drivers, if a younger driver is released because of the same reasons, then legal ramifications would be diminished.

He said the policy could also require drivers who appear to have health issues to have physical examinations once a year rather than the currently required two years. He suggested, too, that operators obtain a copy of the long medical examination form so they have a full picture of the drivers health and know of any ailments they have and medications they are taking.

"If theyre on medicines, you need to know about it because it could have side affects that could impact their driving," he said.

Despite the challenges, he suggested that operators can manage their senior drivers better by looking for obvious signs of problems.

Among the clues he cited are drivers who suddenly begin self-limiting the hours and types of runs they will accept, have an increased number of traffic tickets or near accidents, or begin to get more that the usual number of complaints from passengers.

"They may not want to drive at night any more because of vision problems or they may not want to take drives with a lot of turns because they have joint or bone problems and it hurts them to turn," he noted.

Daecher said there is little chance that federal regulators will set maximum age limits for motorcoach drivers any time soon because of the strong senior citizen lobby in Washington D.C.

"I dont think it will be remedied for many, many years," he said.