Friction rate is a value located on a ductulator. We use it during the design phase of a duct system to predict the operating static pressure of a duct system. The challenge with friction rate is that it is often misapplied by folks using a rule of thumb (ROT). In order to apply friction rate properly, […]

Measuring airflow is easy. Measuring airflow accurately is quite a bit more difficult. In many cases, when we as technicians measure airflow, we are trying to get to the almighty CFM (cubic feet per minute) volume measurement. You can take CFM readings fairly easily with a hood, like the Testo 420, but even a hood […]

“Isaac Newton” by paukrus is licensed under CC BY-SA 2.0 Sir Isaac Newton was an English physicist and mathematician born in a small Lincolnshire village called Woolsthorpe in 1642. His father died before he was born, and his mother remarried when Newton was three years old. He stayed with his maternal grandparents thereafter, and his […]