Trucks at Work

Brake inspections a bigger deal

Traded emails with Daniel Jusdon, inventor and manager of Brake Sentry LLC, the other day about the growing importance of brake system inspections – especially when placed in the context of ever-more contentious debate surrounding the Federal Motor Carrier Safety Administration’s (FMCSA’s) Compliance Safety and Accountability (CSA) program.

Judson pointed out that the reason brake system integrity is so important is that brake adjustment defects account for nearly 30% of all truck crashes and a national out-of-service violation rate of one in every ten vehicles, according FMCSA data – with the average cost to a fleet of an injury accident is $245,000; and the average cost of a fatality is $3.4 million.

Those are but just some of the reasons out-of-adjustment brake violations get pegged with a “4” severity rating within the CSA scoring program, Judson said, making it one of the top equipment violations affecting a fleet’s safety score.

He explained further that one reason driving such “persistently” high out-of-adjustment violation numbers isn’t because automatic slack adjusters (ASAs) for air-brake systems don’t work – they’ve been mandated technology in the trucking industry for over two decades – but because they don’t get properly inspected or maintained.

He contends there are three basic and overlooked facts when it comes to brake system inspections:

  • Although ASAs eliminate the need to perform routine manual adjustments, they do not eliminate the need to perform daily inspections.
  • Unlike manual slack adjusters, ASAs cannot compensate for other deficiencies in the braking system. There are many factors that can hinder proper ASA function and prevent them from maintaining brake adjustment.
  • When a brake equipped with an ASA is out of adjustment, there is a cause and manually readjusting the brake does not address the cause. The problem will remain and the brake will go out of adjustment again.

“Since the brake chamber’s pushrod stroke is physically limited and can only operate effectively within a very narrow range of movement, a mere fraction of an inch of excess stroke can mean the difference between safe and unsafe braking,” Judson emphasized. “It’s worth noting that drivers performing daily pre/post-trip inspections can visually check every item except brake stroke.”

This means that without effective visual brake stroke indicators, the only way a driver can properly check the condition of brake adjustment is to engage in the following actions: chock the wheels, build up air pressure, release the brakes, go to each wheel position, mark each push rod, have the brakes applied at 100 psi [pounds per square inch] system pressure, crawl back under the vehicle and, using a ruler, measure the applied stroke at each brake chamber to see if they fall within the legal limits. 

That’s a lot to ask of anyone, especially when they’re on the clock to deliver a load by a certain time and only get paid by the miles they drive.

Rather than do all of that time-consuming work, Judson believes that many drivers mostly rely on the faulty assumption that brake adjustment can somehow be determined by “feel” or other forms of guesswork.

“This is the main reason drivers are commonly found unaware of existing brake adjustment defects,” he said. “In fact, inspection of brake adjustment by drivers is considered to be one of the major contributing factors to non-compliance.”

This is why the North American Brake Safety Conference recommends the use of what it called “effective” visual brake stroke indicators as “the single most meaningful change that can be made to improve brake compliance,” he noted (and thus not incidentally why he got into the business of making them).

“By eliminating all the guesswork and assumptions, visual brake stroke indicators deliver peace of mind to fleet managers, maintenance personnel, safety-compliance managers and drivers by providing an inexpensive, quick and effective means to visually confirm brake stroke,” Judson added.

Of course, visual brake-stroke indicators aren’t just a smart idea; they are actually mandated by law. Indeed, the Federal Motor Vehicle Safety Standards (49 CFR FMVSS 571.121, S5.18) have always required visual brake adjustment indicators for any brakes equipped with ASAs.

The problem, however, is that such “visual indicators” are almost exclusively some form of colored tape or paint applied to the pushrod, Judson said — and tape wears off, road grime obscures paint color, etc.

Similarly, any indicator design that requires a driver to crawl under the vehicle to measure pushrod stroke defeats the purpose. “This is why practical consideration regarding visibility, durability, operating environment, etc. should be carefully weighed,” he explained.

Something to think about as the safety spotlight continues to be trained ever more closely on all the parts and pieces that form the commercial vehicles plying our roads today. 

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