What is the required color scheme for marking the vapor manifold?

The required color scheme for marking the vapor manifold is based on international safety color codes, which are implemented to ensure proper identification of piping systems and manifolds in hazardous environments, such as on tankers.

The specific combination of red, yellow, and red serves to clearly communicate the presence of dangerous or flammable vapors. Red is often used to signify fire hazards or emergency equipment, while yellow typically indicates caution. Therefore, the arrangement of red, yellow, and red effectively highlights the critical nature of the vapor manifold, ensuring that crew members can quickly recognize its importance and the need for appropriate safety measures when working nearby.

The other choices do not align with the established conventions for marking dangerous systems in maritime operations, as they utilize color combinations that do not provide the same level of immediate recognition and safety awareness concerning vapor hazards.