The National Transportation Safety Board (NTSB) determined that the probable cause of the motorcoach accident in Mexican Hat, Utah, on Jan. 6, 2008, was the driver's diminished alertness due to inadequate sleep resulting from a combination of factors.

The NTSB found that the driver's state of fatigue affected his awareness of his vehicle's excessive speed and lane position on a downhill mountain grade of a rural secondary road.

Contributing to the accident's severity was the lack of an adequate motorcoach occupant protection system, primarily due to the National Highway Traffic Safety Administration's delay in developing and promulgating standards to enhance the protection of motorcoach passengers.

"This tragic accident was entirely preventable," said Acting Chairman Mark Rosenker. "More importantly, it shines a spotlight on the need for all motor vehicle operators to take responsibility for their physical fitness before they get behind the wheel."

Major safety issues identified by this accident investigation included driver fatigue, excessive vehicle speed, hours-of-service violations, motor carrier trip planning, motorcoach occupant protection, and emergency medical notification and response with regard to large motorcoaches traveling on rural roads.

As a result of this accident, the NTSB made eight recommendations to federal and state government agencies, trade associations and the motorcoach operator. Among the most significant are the recommendations to the Federal Highway Administration, the American Association of State Highway and Transportation Officials and the National Association of State Emergency Medical Services Officials to work together to develop and implement criteria based on traffic patterns, passenger volume and bus types that can be used to assess the risks of rural travel by large buses.

A synopsis of the accident investigation report, including the findings, probable cause, and safety recommendations, can be found on the publications page of the NTSB's Website, http://www.ntsb.gov/. The complete report will be available on the Website in several weeks.