PennDOT: Signs are preventing rollovers

PITTSBURGH (AP) -- No tractor-trailers have rolled over on a curved section of Interstate 79 since PennDOT installed electronic message boards warning drivers to slow down.
The section known as the S bends, located on the northbound lanes south of the Ohio River in Allegheny County, saw six tractor-trailer rollovers in the first half of the year -- double the number in the previous five years combined.
All six accidents were attributed to speeding.
The speed limit through the bends is 45 mph. On Oct. 11, PennDOT monitored trucks averaging 59.6 mph -- down from 65.6 mph before the signs were installed, according to Mike Schoss, a district safety manager.
"We have observed most of the vehicles are heeding the speed limit, or at least they've slowed down," Schoss said.
The message boards, set up in late July, warn drivers of the approaching bends and the posted 45-mph speed limit, and also display the speed of approaching vehicles.