NEW YORK (AP)  -- New York City Transit spent nearly $1 billion to install elevators and escalators in the subways since the early
1990s, yet one of every six was out of service for more than a month last year, according to a published report.

And two-thirds of the subway elevators had at least one breakdown last year in which passengers were trapped inside, The New York Times reported Monday.

``This organization is very, very good at subway car maintenance; it's very good at bus maintenance. But maintaining auxiliary equipment it hasn't done as well,'' said Howard H. Roberts Jr., president of New York City Transit. ``I think that we are in the process of trying to create the same competence in elevator and escalator maintenance that we have in buses and subway cars.''

The system has about 200 elevator and escalator mechanics, who receive as little as four weeks of training, a fraction of what they would receive elsewhere, the report said.

``They don't have enough competent people with the proper training,'' said Michele O'Toole, president of J. Martin Associates, which the transit agency hired in 2006 to evaluate its elevator operations.

O'Toole's company quit as a consultant in January 2007 after disagreements with the transit agency and another contractor.

Among the report's other findings:

_ The 169 escalators in the subway averaged 68 breakdowns or repair calls each last year. Some of the least reliable escalators are also some of the newest.

_ Managers often rush balky elevators and escalators back into service without identifying the underlying causes of mechanical problems.

_ Many problems occur because of design flaws or construction mistakes.

The number of elevators has grown since 1990, when the Americans With Disabilities Act spurred changes in the aging system. Out-of-service elevators especially affect disabled riders, who need them to navigate the subways.

In 1990, about 48 elevators were in the subway system. Today, there are 167 in 62 stations, with about two dozen more under construction and many more planned.

Five million people ride the subway in New York City every day.

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