Interference-free measurement of aromatic hydrocarbons for pollution control & environmental monitoring. The MOCON-Baseline Series 9100 on-line GC delivers direct, continuous, real-time measurement of BTEX, 1,3-butadiene, VOCs, and other harmful air pollutants released from industrial sites. The GC provides reliable, accurate detection using one of two available photoionization detector (PID) options. The first, a standard PID with an MDQ for benzene of <1 ppb without preconcentration. The second, a high-sensitivity PID with an MDQ for benzene of <0.05 ppb without preconcentration. The elimination of preconcentration cuts analysis time, cost, complexity, maintenance and efficiency issues.