The recent shift in commercial swine breeding-gestation-farrowing facilities to incorporate filtered ventilation systems raises numerous questions about system performance and longevity of filters. It has been shown that air filtration with ASHRAE standard MERV 14, 15 and 16 type filters are effective at reducing the aerosol spread of PRRSV and Mycoplasma hypopneumonia. The areas that are lacking in current literature is relevant filter testing methodology and criteria for determining filter end of life in an agricultural setting. To address this, a mobile air filter testing unit (MAFT) was developed to address the testing needs for the swine industry to evaluate on-site filter performance. The test duct is capable of measuring pressure drop and airflow for a pre-filter and main V-bank filter combination. The unique feature of this system is the ability to test filters on site and to test the same filter at different points in time. It was shown through validation that MAFT was accurate at measuring the airflow through the filter combinations in comparison to an ASHRAE 52.2 standard lab