In a dual air brake system, what ensures that if one service brake circuit fails, the other circuit can still provide braking action?

Question: In a dual air brake system, what ensures that if one service brake circuit fails, the other circuit can still provide braking action?

Answer options:

• The use of multiple air compressors.
• The presence of a separate wet tank for each circuit. ✅ Independent air lines and reservoirs for the front and rear axles (or primary/secondary circuits).
• A manual bypass valve that diverts air.

Correct answer: Independent air lines and reservoirs for the front and rear axles (or primary/secondary circuits).

Explanation: Dual air brake systems divide the service brakes into two independent circuits, typically one for the front axle and one for the rear (or primary and secondary circuits), each with its own reservoir and supply lines. This redundancy maintains braking capability even if one circuit experiences a failure.