Millwright Level 1 Practice Exam 2025 - Free Millwright Practice Questions and Study Guide

The first step before using a vernier height gauge is to zero the vernier to the reference surface. This process ensures that measurements taken will be accurate from a known baseline. When the vernier gauge is zeroed to the reference surface, it allows for consistent readings against that set reference, which is critical for precision in measuring heights or depths. This step establishes a reliable starting point and is essential for effective and accurate measurements.

In the context of using a vernier height gauge, other steps such as calibrating to the manufacturer's instructions, cleaning the measuring surfaces, or checking for any visible damages are important but usually follow the zeroing step. Cleaning surfaces can help ensure accurate readings but should be done after zeroing to confirm that nothing interferes with the measurement. Checking for visible damages is crucial for safety and functionality but does not replace the need to establish a measurement reference. Calibration is a routine maintenance step rather than an immediate prerequisite for usage. Thus, zeroing the gauge is the most critical initial step for effective operation.