Brake pads are the devices in a car's braking system that bear the brunt of the frictional force it takes to stop a car. Similar to the way bicycle brakes work, on a car with disc brakes, calipers squeeze against the rotors of a car's tires with the brake pads positioned between the calipers and rotors (like the little rubber pieces on a bicycle caliper). The brake pads absorb the energy and heat and provide enough "grip" to stop the car.
Most modern brake pads are semi-metallic; made mostly of copper, brass, and steel wool shavings held together with resin. They are designed to last for thousands of miles.
Brake Pads and Asbestos
For decades, the brake pads installed on most cars were not semi-metallic. They were made of organic materials, including both asbestos and carbon. Asbestos was used for several reasons, including its strength, its ability to resist heat and fire, and its low cost.
However, the use of asbestos in brake pads also presented a hazard. While the long, thin fibers of this toxic mineral didn't pose a dangerous to car owners in general, professional auto mechanics and those who tinkered with their cars in their home garage were probably exposed to asbestos dust whenever they worked on cars with asbestos brake or clutch pads.
As asbestos brake pads wear down, asbestos is exposed and fibers are released into the air. The dust can also gather on other brake parts. Mechanics would often blow dust away with an air hose, not realizing that they were causing dangerous particles to be released into the air, where they were easily inhaled by the mechanic and those around him.
Despite the asbestos warnings of the 1970s and 80s, asbestos can still be found in older cars. As a matter of fact, records show that Ford was using asbestos in the brake pads of their Crown Victoria as late as 1993. Some high-end vehicles still make use of asbestos brake pads. Furthermore, brake and clutch pads purchased on the aftermarket or from foreign wholesalers where asbestos is still used might also contain the hazardous mineral.
Because it is impossible to tell whether or not a car has asbestos-containing brake pads merely by looking at it, mechanics should always exercise caution when working on a car's brake system by wearing a respirator or other protective mask.
Last modified: December 28, 2010.