A study from the University of Iowa College of Public Health has found that traffic accidents involving farm vehicles in the U.S. Midwest would fall by more than 50% if state policies required more lighting and reflection on those vehicles.

The American Society of Agricultural and Biological Engineers (ASABE) issued standards on lighting and marking farm vehicles suggesting certain numbers of headlights, taillights, turn signals, and other exterior lighting visible to other drivers, as well as the number and size of reflective markers.

The organization’s standards are not all required by state laws, but many of the nine states in the study have adopted some of them or have their own policies that address the same issues.

Many passenger-vehicle drivers cannot correctly gauge the speed at which they are moving. Image credit: Pixabay.The researchers found fewer crashes in states with more stringent lighting and marking policies, in particular those that adhered to ASABE’s standards. States with greater compliance with ASABE standards had 11% fewer farm equipment road crashes than states with lower rates of compliance.

Using data from 2005 to 2010, the researchers estimate the number of accidents annually would be cut 60%, from 972 to 385, if states implemented policies that increased compliance with ASABE standards by 25% over current practices.

Most farm vehicle-related accidents occur because passenger vehicle drivers cannot correctly gauge the speed at which they are moving, says Marizen Ramirez, professor of occupational and environmental health and lead investigator on the study. This often leads to vehicles approaching too quickly and attempting to pass in unsafe conditions, which can result in a crash.

She says the likelihood of a crash is greater in October and November, when more farm vehicles are on the road for the harvest and the sun sets earlier.