The cleaning strength of a PCB cleaner is frequently measured using an industry benchmark called the Kauri Butanol (Kb) value. A higher Kb value is usually better and means the cleaner is more aggressive. But there are trade-offs. For instance, stronger solvents can have compatibility problems with plastics, coatings, inks and other components. So, smart engineers should examine the Kb value of their cleaning products to avoid expensive surprises.