Mitchell 1, a Snap-on Company, has added color air brake diagrams to, its comprehensive web-based truck repair manual system. The pneumatic diagrams will include the same widely used features as the electrical wiring diagrams. In addition, the line colors were designed to conform to TMC's Recommended Practice 423.

Each diagram mirrors the colors of the pneumatic brake line on the truck, allowing technicians to highlight the line being worked on. All diagrams are oriented the same, regardless of manufacturer.