Certified Safety Professional Exam 2026 – 400 Free Practice Questions to Pass the Exam

A thermal anemometer measures air velocity by detecting temperature changes caused by the movement of air over its sensor. For optimal measurement, it should be positioned perpendicular to the airflow. This orientation allows the full airflow to impact the sensing element, ensuring accurate readings of the air velocity.

When the anemometer is perpendicular to the airflow, it can capture the maximum possible flow, which is critical for obtaining reliable data. If positioned parallel to the airflow, it may underestimate the velocity, as not all of the air movement would be directed across the sensing element. An angle to the airflow could lead to inconsistent results, as varying degrees of airflow could produce different readings. Placing the anemometer in a corner of the duct is not effective as airflow dynamics can be unpredictable in such locations, leading to potential turbulence that distorts measurements.

Thus, the optimal position for a thermal anemometer is perpendicular to the airflow, ensuring accurate and reliable data collection.