Is it permissible for the conductor to close both angle cocks to conserve standing train's air after the cars have been in storage for two months?

The correct response to whether it is permissible for the conductor to close both angle cocks to conserve the air in a standing train after the cars have been in storage for two months is grounded in safety considerations. Closing both angle cocks, which isolates the air supply to the braking system from the rest of the train, is referred to as "bottling the air." This practice can create significant safety hazards.

When angle cocks are closed, the air brakes on the isolated cars become inoperative because they cannot receive air pressure from the main reservoir. In the event of an emergency or if a need arises to move the train, the brakes will not function correctly, increasing the risk of accidents or unintentional movement. Moreover, it can lead to issues with maintaining proper brake system integrity and pressure.

Thus, safety protocols dictate that both angle cocks should remain open to ensure that all cars on the train have access to a functional air brake system, allowing for immediate response to operational needs or emergencies.