Question
How does one measure air velocity in a cold storage facility. I'm looking for a measuring device for checking airflow in our cold storage facilities in the corners, between pallets and walls. Is there a recommended minimum target air flow in a produce cold storage? (J.M.)
Answer
I recommend buying a hot wire anemometer. You can get a very nice one from Alnor for about $600. These devices also measure air temperature accurately and respond very quickly to changes in temperature. With the anemometer set to read air temperature, you can quickly walk through a cold room and check for warm or excessively cold areas.
I do not usually keep track of airflow in storages in terms of air speed, but I prefer air volume per ton of product. I recommend 100 cfm per ton of product when product first enters cold storage and is not completely cooled to storage temperature. This corresponds to air speeds in the range of 20 to 100 fpm. If moisture loss from product is a problem, then you would like the lowest possible airflow that will maintain uniform product temperature, usually 20 to 40 cfm/ton. Product temperature variability is a key variable to measure to determine if airflow is adequate, not just air speed. –