Method detection limits (MDLs) have been determined for the newly regulated HON (Hazardous Organic NESHAP (National Emission Standards for Hazardous Air Pollutants)) compounds, which validate selected ion flow tube mass spectrometry (SIFT-MS) as an effective solution for measuring these toxic volatile organic compounds (VOCs) and other environmental pollutants in ambient air, whether at the fenceline or in a mobile setting. SIFT-MS offers unparalleled speed, sensitivity and ease of use for environmental monitoring applications.