The Kentucky Department for Environmental Protection has been developing on-site monitoring capability for the measurement of air pollutants. The department has purchased a mobile laboratory equipped with a GC/MS for point monitoring and a long-path Fourier transform infrared (FT-IR) remote sensor unit for monitoring air pollutants at different locations in the State. Prior to deploying the FT-IR instrument in the field, the instrument has been evaluated for precision and accuracy with 15 certified gases (CO, NO, NH3, COS, CS2, SO2, (CH3)2S, acetone, benzene, CH3OH, CH4, CCl4, CCl3H, C2H5OH, and H2S) against the vendor provided calibration spectra by using a 15 cm quality control internal cell. Results of this study are presented. Some other studies include the cases of strong spectral overlaps and structured spectral features. Results of some short-term field study at Calvert City, Western Kentucky are also presented.