Which of the following is NOT part of the general application process for coal tar enamel?

The option indicating that applying a third layer of coal tar dope is not part of the general application process for coal tar enamel is accurate. The application of coal tar enamel typically involves a specific sequence aimed at achieving the best protective qualities and adhesion.

In standard procedures, layers are applied systematically to build up the coating's thickness and effectiveness. It is common to use certain materials and methods in these processes; however, the specific application of a third layer of coal tar dope isn't a widely recognized step in the typical application process for coal tar enamel. More often, a certain number of layers or a specific type of finish is required, and not necessarily a third layer of dope after a prescribed application has been completed.

Other elements of the application process, such as cooling the application, wrapping with fiberglass mat, and priming the pipe, are standard practices that contribute to the overall durability and integrity of the coating. Cooling helps in ensuring proper application temperature, which is critical for adhesion. Wrapping with fiberglass mat enhances the mechanical properties of the coating, and priming is essential to ensure sufficient bonding between the substrate and the enamel. These steps are integral to achieving optimal performance from the coal tar enamel system.