WASHINGTON – Highway regulators have failed to act on more than 100 recommendations to improve truck safety at a time when fatalities have risen for four straight years, according to the National Transportation Safety Board.

Priorities must change in 2015, with more anti-collision technology, better limits on driver hours and tighter regulation of trucking companies with high accident rates, the NTSB said Tuesday.

The accidents that injured comedian Tracy Morgan in June and killed four members of a college softball team in September cast new light on the United States' 2 million truckers, who are involved in crashes that kill almost 4,000 people a year. The NTSB said it's time for regulators to act on its more than 100 recommendations to improve safety.

"There's a whole suite of technology that's ready for prime time now that would reduce crashes," said Donald Karol, NTSB's director of highway safety investigations.

The NTSB is pushing the use of sensors to warn truck drivers when they're about to strike someone from behind or to alert when a vehicle changes lanes.

The agency made the plea as it unveiled its "Most Wanted List" of transportation improvements for 2015. In addition to trucking, the NTSB also said more attention should be given to rail tank-car safety, airline pilot compliance, distracted driving, and drug and alcohol impairment.

"The Most Wanted List is our road map for 2015," Christopher Hart, NTSB's acting chairman, said.

The NTSB, which investigates transportation and pipeline accidents, has no regulatory authority. It uses its annual Most Wanted list to highlight the areas most in need of improvement.

While transportation has become safer in recent decades, the tens of thousands of deaths each year and hundreds of thousands of injuries indicate "we have a long way to go," Hart said.

One issue is driver fatigue, the NTSB said. The safety board has recommended that trucking companies impose plans to better manage fatigue on the roads.