Cars and trucks require a lot of maintenance and attention. After oil changes, car washes, new tires, and new windshield wipers, it is easy to forget less-obvious tasks, like cleaning your brakes. When it’s time to clean residue off brake pads, linings, drums, and cylinders, the two most common solvent options are chlorinated and non-chlorinated brake cleaners. Both get the job done, but understanding their key differences can prevent maintenance and safety issues.
Chlorinated and non-chlorinated brake cleaner both contain toxic chemicals, though chlorinated solvents contain the more harmful ingredients between the two. Chlorinated brake cleaners are comprised of Perchloroethylene (Perc), Methylene Chloride (MeCl), and Trichloroethylene (TCE), which are considered Volatile Organic Compounds (VOCs). As an alternative, non-chlorinated brake cleaners entered the market at a slightly higher cost with less environmentally impactful chemicals, such as acetone, heptane, isopropyl alcohol, and other low-toxicity petroleum hydrocarbons, such as mineral spirits or toluene.
For an auto shop concerned with employee safety, the difference in VOC emissions is no small detail. According to the EPA, VOCs pollute the environment in the form of gaseous emissions that can cause serious side effects in humans and animals. These side effects include headaches, nausea, loss of coordination, kidney and liver damage, and some cancers. As a result, chlorinated brake cleaners have since been banned in California.
Despite those less toxic properties, the chemicals in non-chlorinated brake cleaner are highly flammable. This makes them inappropriate for vapor degreasing and other more complex cleaning applications. Their drying time is slightly longer than chlorinated solvents, which is one of their largest trade-offs along with somewhat lower solvency. But don’t be fooled. While a chlorinated solvent may be toughest on grime, non-chlorinated alternatives are still much more powerful than water-detergent solutions, especially on paint and other substances.
Remember to keep these differences in mind when maintaining clean, healthy brakes. Check your local regulations on legal and illegal solvents and weigh the potential consequences and benefits. For more literature on solvents and safety assessments, you can also visit the Dow Chemical Company at Dow.com.