What is the first step in performing the main drain test?

The correct first step in performing the main drain test is to observe the pressure. This initial observation is crucial because it provides baseline data regarding the water pressure in the system before any adjustments or changes are made. By measuring the pressure beforehand, inspectors can compare the results of the test against these baseline readings to determine if the system is functioning properly or if there are any issues that need to be addressed.

Understanding the initial pressure is essential for evaluating the overall health of a fire protection system. It helps to identify if there are any leaks, blockages, or other problems that could compromise fire safety. This step sets the stage for the rest of the tests involving the valve action and flow rate, ensuring that the assessment is thorough and reliable.