What effect does higher ambient temperature have on vapor recovery efficiency?

• A. It decreases vapor pressure and emissions
• B. It has no effect on vapor recovery
• C. It can increase vapor pressure, leading to greater emissions
• D. It improves the efficiency of all vapor recovery systems

Answer: (C)

Higher ambient temperatures can significantly impact vapor recovery efficiency, particularly by affecting vapor pressure. As ambient temperature increases, the vapor pressure of the gasoline or liquid being stored also rises. This is due to the fact that warmer temperatures provide more energy to the molecules, allowing more of them to escape into the vapor phase.

When vapor pressure increases, it translates to a greater amount of vapors being produced and potentially released into the atmosphere during the fueling process. This increase can lead to a higher volume of emissions that the vapor recovery system needs to manage. Therefore, the ability of the vapor recovery system to effectively capture these emissions during fueling operations becomes more critical.

It is important to understand that while improved system designs can mitigate some of these effects, the fundamental relationship between temperature and vapor pressure remains a key factor in the efficiency of vapor recovery systems. This makes it clear why the correct answer highlights the link between higher ambient temperatures and increased emissions due to elevated vapor pressures.