ADA helps keep U.S. elevator market strong

Of the 5.8 million elevators in the world, 760,000, or 13 percent, are in North America, according to the industry publication Elevator World.

The majority of the world's elevators are traction-type, which are usually found in taller buildings. Traction elevators traditionally use steel cables that wrap around a sheave and connect both to counterweights and to the elevator car.

However, 85 percent of elevators in North America are hydraulic, which are usually found in low-rise buildings. These are operated by oil, which is pumped by a power unit that is typically below grade. As the oil is pumped, it lifts the elevator.

The elevator industry is somewhat insulated from the current economic downturn in part because of the Americans with Disabilities Act (ADA), which requires that facilities be accessible, according to Rory Smith, ThyssenKrupp's vice president of product planning. Smith says that without the ADA, many small, low-rise buildings in the United States would not have elevators.

New technologies have resulted in another industry trend: elevators that do not require machine rooms. These place all machinery within the elevator shaft itself, leaving more usable space in the building for other systems.

New technology for these machines includes synchronous electric motors that are smaller than traditional motors and have higher efficiencies and improved suspension systems that reduce torque.

Machine room-less elevators use special traction belts that utilize smaller motors with higher efficiencies and improved suspension systems. This significantly reduces the size of equipment, and therefore, the installation costs as well.