What are CARB's most recent vapor recovery regulations known as?

The correct choice is C, as CARB's most recent vapor recovery regulations are referred to as Enhanced Vapor Recovery (EVR) regulations. These regulations were developed to improve the efficiency of vapor recovery systems and minimize emissions from gasoline dispensing operations. The EVR program is designed to ensure both compliance with air quality standards and the protection of public health by reducing harmful vapors released during the transfer of fuel.

By establishing stricter performance standards and requirements, CARB aims to enhance the effectiveness of vapor recovery systems, ensuring that they capture a greater percentage of volatile organic compounds (VOCs) emitted during refueling. This is particularly important in locations where air quality is a significant concern.

The other options, while they may sound related, do not represent California Air Resources Board's (CARB) most recent regulations on vapor recovery. Understanding the specifics of the EVR program helps ensure compliance and improves environmental outcomes, making it a critical focus in the realm of vapor recovery installation and repair.