IT PAYS TO BE SAFE

No. 12, March, 2010
Vehicle Control-Braking Systems

Pursuant to 49 CFR 383.111, all commercial vehicle operators must have knowledge of the general restrictions to safely control their vehicle. This includes knowledge of basic control procedures, shifting, backing, visual searches, communications, speed management, space management, night operation, driving in extreme conditions, hazard perceptions, emergency maneuvers and skid control and recovery.

In order to satisfy that obligation, a commercial driver is required to have knowledge concerning their vehicle's airbrake systems. This includes understanding the airbrake system's terms, the dangers presented by contaminated air supply, the problems presented by severed or disconnected airlines between the power unit and the trailer, implications of low air pressure readings, as well as procedures for conducting safe and accurate pre-trip inspections, as well as conducting those inspections while en route and post delivery.

One, if not the most, important responsibility of a truck driver is to have the ability to properly inspect his/her vehicle's braking systems. In fact, this is a prerequisite for obtaining a commercial driver's license. A driver must have the necessary knowledge to:

• locate and verbally identify airbrake operating controls and monitoring devices;
• determine the motor vehicle's brake system's condition for the proper adjustments;
• check that the air system connections between the motor vehicles have been properly made and secured;
• inspect the low-pressure warning devises to ensure they will activate in emergency situations;
• ascertain (with the engine running) that the system maintains an adequate supply of compressed air;
• determine that required minimum air pressure build-up time is within acceptable limits;
• that required alarms and emergency devices automatically deactivate at the proper pressure level; and
• operationally check the brake system for proper performance. 49 CFR 383.113(c).

The specific system requirements are provided in §393(c). These regulations include the specifications that brake chambers, slack adjusters, linings and pads, and drums and rotors must have in order to be compliant and functioning satisfactorily. We will be covering the exact specifications in the next few editions of It Pays to be Safe.

A commercial driver has the responsibility to maintain control of their vehicle at all times. Ensuring that the braking systems and components on a commercial vehicle are operational before and after a trip is one of the most important tasks a driver can complete. Knowledge of a braking system's requirements and specifications allows a driver to competently inspect their vehicle in order to ensure that it does not pose a hazard to the public or themselves.