Photo courtesy of Traylor Bros. Traylor Bros.' Amcon 150 barge-deck winch is one of the 3,000 pieces of equipment that need added attention due to Tier IV Final rules. Photo courtesy of EMI-Global In order to meet Tier IV Final emission rules, equipment must have dozens of sensors and actuators, leaving little free room under the hood. Related Links: Clean-Air Costs Will Come in Stages, Caterpillar Says Why Contractors Are Renting More And Buying Less Fleet owners are struggling with new federal emission rules effective this year for off-road diesel-powered trucks and machines. The U.S. Environmental Protection Agency's Tier 4
Arch dams, classically curved monoliths situated in narrow valleys, are not as common as other types of dams, such as embankment dams and gravity dams. ENR takes a look at some of the biggest arch dams in the world, both completed and under construction.