What does the steam pressure gauge indicate?

The steam pressure gauge is a crucial instrument in boiler operations, specifically designed to indicate the pressure of the steam within the boiler. This measurement is vital because it helps operators monitor the functioning of the boiler system and ensures it operates safely and efficiently. Maintaining the correct steam pressure is essential for optimal boiler performance and helps prevent potential hazards such as overpressure situations.

The other options do not accurately describe the function of the steam pressure gauge. For instance, the gauge does not provide information on water temperature or the level of water in the boiler, which are measured by different instruments such as a thermometer and a water level gauge, respectively. Additionally, while the volume of steam produced is an important aspect of boiler operation, the pressure gauge specifically reflects pressure rather than volume. Thus, understanding the steam pressure gauge's role is critical for effective boiler management and safety.