The NEBB Professional 2025 - Quarter 3

WAR STORIES The Evo luti on of TAB Ins trume nts

By TAB Committee members

Anyone who started doing TAB work in the 70s and 80s can tell you the limits of how things could be done in the field. The instrumentation was mainly analog type devices, while tracking and keeping up with in formation was done by recording values on a piece of paper or document. The field technicians that per formed a TAB project required everything to be docu mented on a mechanical drawing, and paperwork and was then brought back to the office to be typed into a report format. When faced with challenges and proper methods for testing, utilizing some of the technolo gies and equipment we have today was not an option. While this article will not cover all of today’s equip ment, it will outline what was used for different appli cations or methods of testing in the past as a means of

offering some of the younger generations of engineers and technicians a brief history lesson in our field.

Incline Manometers Below is a picture of a Dwyer 10” incline manometer that can read velocities from 0 - 12,500 FPM and a 0-.25” w.c. Both meters could be used for doing tra verses, as well as static pressure readings. The meter had to be set up and leveled, with the red oil confirmed level and zeroed out at the start of the readings. When determining total airflow by traverse or simple static pressure readings, two individuals were required: one to hold the pitot or static tube in the duct to obtain the reading, and the other to observe the incline and re cord the value. When inserting the pitot tube, one had

The NEBB Professional | Quarter 3 | 2025

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