An important aspect of professional truck driving is the pre-trip inspection. Regulated by federal law, truck drivers are required under FMCSA Regulation §383.113 (2) (ii) to be able to “determine the motor vehicle’s brake system condition for proper adjustments and that air system connections between motor vehicles have been properly made and secured.”
Veteran drivers understand all to well, the seriousness of an air brake failure while operating a Commercial Motor Vehicle. Many truck accidents have occurred due to the loss of brakes which have led to the driver being cited for failure to properly inspect the brake system. When law enforcement is unable to determine the actual cause of such accidents, many times it is reported as due to driver fatigue.
A serious safety issue that continues to be overlooked and under-reported is the problem of Treadle Valve corrosion, specifically with the E6 and E10 Foot Brake Valve. As a majority of accidents have been reported as being caused by truck driver fatigue, the true underlying culprit could actually be the unseen corrosion that is blocking the plunger and the valve, preventing the Treadle Valve from operating properly, thus leading to the brake failure accident. Watch video
The Commercial Vehicle Safety Alliance (CVSA) released the 2012-2 Inspection Bulletin detailing the procedures for inspecting the brake pedal (valve and treadle) assembly.
According to Allan Tow, a 30 year trucking veteran and consumer advocate for the prevention of truck accidents, “If the treadle valve sticks in the up position, the plunger in the valve housing will not go down and any accident will not be the fault of the driver.”
If the plunger sticks in the center, the air pressure supplied to the brake chamber will result in an amount that will only lead to brake drag. This “drag” is what can lead to the brakes heating and resulting in a fire. Again, with the plunger stuck in the middle, the driver would have no way of knowing that anything is wrong since this would not cause the brake warning light to come on.
Finally, should the Treadle Valve become stuck in the down position, the brakes will most likely lock up and be unable to release, causing the 18-wheeler to go into a skid. Again, no fault by the driver.
The National Highway Traffic Safety Administration (NHTSA) first began recalling Treadle Valves in the 1970’s and most recently, in August of 2012. Due to the fact that there are more semi tractor trailers on the road today, along with many more various types of chemicals being used on the highways, the safety issue with Treadle Valves is becoming more prevalent.
Yet, even today, there is no serious industry study being performed in order to investigate the air brake valve problem. There is no doubt that truck drivers are being faulted for improper vehicle inspection or driver fatigue when in fact, it is due to defective brake valves that can be virtually undetectable by the driver and law enforcement officials.
Catch our interview with Allan Tow and Rickey Gooch on Truth About Trucking “LIVE” : Trucking Safety: Investigating the E6 and E10 Brake Valves.
Allan’s Website AirBrake Info