What should be the scale range of a positive-pressure analog indicator?

The correct scale range for a positive-pressure analog indicator is ideally within 50% of the gauge scale. This range ensures that there is a clear and accurate representation of the pressure being monitored, which is critical in medical gas applications where precise pressure readings are vital for patient safety and equipment functionality.

When the indicator is calibrated within this range, it allows users to easily differentiate between normal and abnormal pressures. It also aids in identifying any malfunctions or deviations in the pressure that could lead to complications in gas delivery systems. A gauge that operates within this optimal range enhances the reliability of the system, ensuring that medical gases are delivered at safe and effective pressures.

The other options suggest different ranges, which may not provide the same level of clarity or safety in monitoring pressure. A gap beyond 50% can obscure critical readings needed for effective management of medical gases.