Technical Standards and Safety Authority (TSSA) G3 Practice Exam

The diameter of a drip or dirt pocket shall be equal to the diameter of the piping or tubing that it serves, or:

1. 1 inch (25 mm)

2. 2 inches (50 mm)

3. 3 inches (75 mm)

4. 4 inches (100 mm)

The correct answer is: 2 inches (50 mm)

The requirement that the diameter of a drip or dirt pocket must be equal to the diameter of the piping or tubing it serves, or a specified minimum size, is crucial for ensuring effective drainage and maintenance of the system. This design consideration helps prevent blockages and ensures that any accumulation of condensate or dirt can be effectively managed. In this context, the value of 2 inches (50 mm) serves as a practical minimum size that balances the need for effective drainage with the space constraints often present in piping systems. A pocket of this size is typically sufficient to allow for the ample passage of water or debris that may enter the system, while not being overly large, which could lead to unnecessary material costs or installation challenges. The other diameter options presented do not represent the minimum requirement in common practice, making 2 inches the most suitable choice. By adhering to this standard, the overall safety and efficiency of the plumbing or gas distribution system are maintained, minimizing potential operational issues that could arise from inadequate drainage.