What does CP-201 state about liquid traps in dispenser vapor piping?

• A. Not allowed
• B. Allowed only with an assist system
• C. Allowed if approved by the Phase II system manufacturer
• D. Allowed when hoses with liquid removal systems are used

Answer: (A)

CP-201 explicitly states that liquid traps in dispenser vapor piping are not allowed. The reasoning behind this regulation is rooted in the need to maintain the efficiency and safety of vapor recovery systems. Liquid traps can create points of blockage or accumulation within the vapor recovery system, leading to an increased risk of vapor leaks and reduced overall performance of the phase II vapor recovery system.

Keeping vapor piping free from liquid traps ensures that vapors can flow smoothly and be recovered effectively during refueling operations. Furthermore, any trapped liquid may interfere with the proper functioning of vapor pumps and other components, potentially leading to system failures. This prohibition is designed to uphold environmental standards and enhance operational safety.

The other options involve scenarios that permit the use of liquid traps under certain conditions, which CP-201 does not endorse.