The Personal Ozone Monitor (POM) has dimensions of 4 x 3 x 1.5 inches and weighs only 0.75 lb (340 g). It has a built in GPS so that ozone measurements may be logged continuously along with geographic location. By folding the optical path in the shape of a “U”, it was possible to achieve the same path length in the POM as in much larger models such as the 202, 205 and 106-L and thus have similar precision and accuracy (~2 ppb).
