The Model N901 is a near-continuous hydrocarbon gas analyzer that measures the concentration of Methane (CH4) and Total Hydrocarbons (THC) in air. The concentration of the non-Methane (NMHC) component is calculated by the subtraction of CH4 from THC, with high sensitivity and accuracy. The hydrocarbons are measured using a Flame Ionization Detector (FID), in combination with gas chromatography (GC). The instruments range and performance are tuned specifically for use in ambient air quality monitoring assessments. 

The Model N901 is designed for simple operation and maintenance with a modular hardware and electronics architecture. A long-life stainless-steel fritted filter is used at the sample intake to effectively remove particulate matter without introducing any gas-phase measurement artifacts. Instrument operation, calibration functions, chromatogram views,​ and data handling are all automated and controlled using the internal NumaView™​ Software (NVS) interface, without the need for an external PC.​

For remote connection to the N901 instrument, Teledyne API's NumaView™ Remote PC-based Software provides a virtual interface, instrument controls, and data downloading capability to all TAPI analyzers operating NumaView™ Software.​