A collection of information on the regulation, design, performance, operation and maintenance of air-braked vehicles was reviewed. These data indicate that performance decrements arising from the sensitivity of air-braked vehicles to maintenance has been a safety issue for a considerable period of time. The predominant reason why air-brake vehicles are placed out-of-service at roadside inspections continues to be, predictably, due to maintenance-related braking problems. The ability of drivers to safely maintain control of air-braked vehicles can seriously be restricted when maintenance-related braking problems reduce the braking performance or the limited reserve braking capacity of service (foundation) brakes. Primary safeguards that mainly rely on the vigilance and knowledge of drivers to know whether brake repairs are warranted when daily pre-trip inspections are conducted may be inadequate. There are currently no requirements for a cab-display device to readily alert drivers when the stopping capability of air-braked vehicles has deteriorated to an unsafe level. Comments about the need, feasibility and merits of a low-cost cab-display brake fault indicator lamp for air-braked vehicles are presented. (A)
Abstract