If a boiler was fired with the main steam stop valve closed, the safety valves should ensure that the:
a. Pressure cannot exceed the maximum working pressure by more than 6%.
b. Water glass will not burst with the pressure.
c. Fuel cut-off will operate.
d. Pressure cannot exceed the maximum working pressure by more than 3%.
e. Pressure is never more than the hydrostatic test pressure.
Answer: A