A new portable instrument for continuous measurement of formaldehyde in ambient air

A new instrument for the in situ measurement of formaldehyde with online concentration output was built on the base of the Hantzsch chemistry fluorimetric detection of formaldehyde in liquid phase. The instrument was specially designed for applications in a fast-changing environment, for example, in airborne research. Individual instrument components were optimized to reduce size, weight, and power consumption and to improve response time. The small size, battery-operated system was shown to reach good performance, stable sensitivity, and detection limits of < 100 ppt for temperatures between 0 degrees and 35 degrees C during aircraft flight missions in field campaigns in the Italian Po Valley. The instrument proved its performance with formaldehyde mixing ratios ranging from 0.5 to 25 ppb.