I do not know about other people, but I use Sodium Hydroxide solution mixed 1:1 with water, then sprayed using an airline over the parts. Leave to soak for about 30 seconds to 1 minute, then pressure wash off. Repeat and lightly scrub with a paintbrush for deep-seated contamination.

Remember, this stuff is toxic, so use in a ventilated area and wear hand / face protection.