Vehicles and trains collide an average of nine times a day. More than 1,000 people have been killed in such accidents in the past four years. In the first five months of this year, there were 1,205 crashes, including four involving school buses, and 155 deaths.Those figures, and an accident in Tennessee four years ago that killed three children and injured three others, has prompted the federal government to urge states to give high priority to improving safety at railroad crossings. But only a dozen states followed through, according to a report by the Associated Press.Seven of the 10 states with the most collisions between trains and all kinds of vehicles at grade crossings have largely ignored the National Transportation Safety Board's recommendation. They are Alabama, California, Georgia, Illinois, Louisiana, Mississippi and Ohio.The 82,000 crossings where there are no gates present the greatest danger - the accident rate is seven times that for crossings with gates that block vehicles, according to the AP story.A key NTSB recommendation for such crossings was installation of stop signs. That was seen as a far cheaper alternative to other railroad crossing safety measures, such as installing gates at a cost of $150,000 apiece, building bridges or rerouting tracks or roads.Beyond stop signs, the NTSB recommends equipping school buses with "option kill switches," which enable drivers to turn off noisy devices like fans and radios when a bus approaches a rail crossing. Only Florida and Kentucky require the switches.