In the preamble to the final Respiratory Protection Standard, OSHA discussed extensively its rationale for requiring that employees breathe air consisting of at least 19.5 percent oxygen. The following excerpt, taken from the preamble, explains the basis for this requirement: Human beings must breathe oxygen . . . to survive, and begin to suffer adverse health effects when the oxygen level of their breathing air drops below [19.5 percent oxygen].
- The Tu-144 supersonic transport was the fastest commercial jet plane at Mach 2.35 (1,555 mph, 2,503 km/h). It went into service in 1975, but soon stopped flying. The Mach 2 Concorde aircraft entered service in 1976 and flew for 27 years..
How Fast Does a Commercial Jet Airplane Fly. Commercial jets are by far one of the fastest ways to travel. Each type of jet has its own takeoff, cruising and landing speed. A commercial jetliner usually takes off between 160 and 180 mph. The varying speed can be due to wind resistance, overall weight capacity and/or the use of high-lift devices.