Abstract:Abstract:The temperature pressure velocity transmitter all-in-one monitor (TPVTAIOM) mainly used in continuous emission monitoring system (CEMS) which can measure the flue gas parameters such as temperature, static pressure, dynamic pressure and velocity in real time. Based on the introduction of the composition and measurement principle of TPVTAIOM,the main influencing factors of velocity error and current situation of the technology and verification/calibration were analyzed. For its existing problems, the urgency of developing national standards and national/local verification regulation or calibration specification is proposed.