A pressure gauge on a section IV boiler is graduated to what specifications?

The correct choice reflects the commonly accepted specifications for pressure gauges used on Section IV boilers. These specifications ensure that the gauge can provide accurate readings within a safe and operationally relevant range.

Typically, the requirement for a pressure gauge is that it must be designed to operate within a specific pressure range which allows for adequate monitoring of the boiler's operating conditions. The stated range of no less than 30 psi (200 kPa) nor more than 60 psi (414 kPa) is appropriate for many low-pressure boilers classified under Section IV, as it allows operators to effectively monitor pressures that are typical in such systems while also ensuring that the gauge can safely accommodate any operational pressure fluctuations without risk of failure.

This choice aligns with established safety standards and practices in pressure vessel operation, as exceeding the maximum operational pressures could lead to dangerous situations. Properly calibrated gauges within this specified range allow operators to maintain safe and efficient operation of the boiler system.