The dry gas meter (DTM) is a primary standard for measuring air volume. The AEM Volumetric gas meter, with diaphragm, meets requirements of the International Legal Metrology Organization (OIML) and EN-1359-1998. MAX Flow rate = 2.5 m3/hr (41 LPM), Min flow = .016 m3/hr (0.26 LPM), Min Pressure 0.5 bar, limit error ( Qmin