Powered capture hood

A powered capture hood assembly to measure volumetric airflow comprising:

• a) a hood structure for providing or capturing airflow;
• b) a formed nozzle structure having opposing first and second ends, said first end having means for connecting to said hood structure, said nozzle structure having a generally centrally disposed restricted area forming a venturi in said formed nozzle structure, said formed nozzle structure having a supply sensor and tap and a return sensor and tap;
• c) an airflow conditioning assembly disposed in said second end of said nozzle structure;
• d) a blower apparatus having an adjustable fan therein, said blower apparatus constructed for mounting to said second end of said nozzle structure, said blower apparatus having a pressure sensor and tap for sensing air flow;
• e) means to adjust the fan speed of said blower apparatus;
• and
• f) means to measure the pressure in said blower apparatus, said venturi portion of said nozzle structure and at said second end of said formed nozzle structure.