A new study found that the restart provision in the Federal Motor Carrier Safety Administration‘s current hours-of-service rule is more effective at combating fatigue than the prior hours rule, the agency said.

The “real world, third-party” study, mandated by the MAP-21 transportation law, provided scientific evidence that the restart provision helps “truckers stay well-rested, alert and focused on the road,” Transportation Secretary Anthony Foxx said in a Jan. 30 statement.

The hours rule, which became effective July 1, requires any driver working long enough to need a restart to take off at least 34 consecutive hours that include two periods between 1 a.m. and 5 a.m.

The study found that drivers who began their work week with just one nighttime period of rest, as compared with the two nights in the updated 34-hour restart break, exhibited more lapses of attention, reported greater sleepiness and showed increased lane deviation in the morning, afternoon and at night.

“This new study confirms the science we used to make the hours-of-service rule more effective at preventing crashes that involve sleepy or drowsy truck drivers,” FMCSA Administrator Anne Ferro said. “For the small percentage of truckers that average up to 70 hours of work a week, two nights of rest is better for their safety and the safety of everyone on the road.”