Which statement is true about glad-hand color coding?

Which statement is true about glad-hand color coding?

• A. Blue is service
• B. Red is emergency
• C. Green is service
• D. Yellow is emergency

Answer: (A)

Glad-hand color coding keeps the correct air lines from being mixed up between a tractor and a trailer. The standard scheme uses blue for the service line, red for the emergency line, and yellow for the trailer supply line. The service line (blue) carries air to operate the trailer brakes during normal braking. The emergency line (red) provides air to the emergency brake valve and will trigger brakes if pressure is lost. The supply line (yellow) keeps the trailer reservoirs pressured so brakes stay released. So blue being service is the true statement. Green isn’t the standard service color, and yellow isn’t the emergency color.

Glad-hand color coding keeps the correct air lines from being mixed up between a tractor and a trailer. The standard scheme uses blue for the service line, red for the emergency line, and yellow for the trailer supply line. The service line (blue) carries air to operate the trailer brakes during normal braking. The emergency line (red) provides air to the emergency brake valve and will trigger brakes if pressure is lost. The supply line (yellow) keeps the trailer reservoirs pressured so brakes stay released. So blue being service is the true statement. Green isn’t the standard service color, and yellow isn’t the emergency color.