TABmaster Flow Hood 6715 for Exchange Rate Calculations for IAQ Investigation

6715 for IAQ Exchange Rate 3.22.18

As buildings have become “greener”, heating and cooling efficiency have greatly improved.  However, this increased building tightness can have a negative impact on the indoor air quality of the building if the HVAC system isn’t pulling in enough outside air.  How can you be sure that the occupants of a building are getting enough fresh air?

The calculation is actually really simple.  ASHRAE Standard 62 lists the recommended volume of fresh air needed for various indoor environments.  For example: an office building should have 20 cfm of outside air per occupant.  So if you’re checking the volumetric flow for a small office with 15 occupants it should be at least 300 cfm (15 people x 20 cfm of outside air per person = 300 cfm of outside air).

The tool of choice for this measurement is the Capture Hood.  This instrument can measure the volumetric air flow coming into the building directly at the outdoor intake point.  A Capture Hood can quickly measure volumetric flow accurately and without the need for extra calculations or multiple point measurements at the same source.  In addition to measuring the amount of outdoor air entering the building, a Capture Hood can also identify if the exhaust and intake ducts in each room are performing as expected.


The Kanomax TABmaster is an affordable, light-weight precision instrument that’s easy to setup and use.  A single technician can quickly take many measurements in a short time, save the data, export it to a PC and analyze it to get a clear picture of how the HVAC system is performing and identify problem spots for the client.

Click here for more details about the TABmaster 6715.