The safety valve is set automatically when pressure is:
Answer: A
150
The primary air tank contains a safety relief valve to protect the air system from excessive pressure buildup. The safety relief valve typically activates at 150 psi.
All choices
- A150
- B100
- C50
Why the other answers are wrong
B. 100
Choice B is wrong because 100 psi is below the typical safety valve activation pressure of 150 psi.
C. 50
Choice C is wrong because 50 psi is too low for the safety valve setting, which protects against excessive pressure.
CDL Air Brakes Test Info
Questions on Exam
25
Passing Score
80%
Time Limit
Typically 30 minutes; varies by testing location
The Air Brakes test content is federally standardized, so this question applies in every state. Age limits, fees, and testing procedures do vary — check your state's CDL requirements.
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