This part of IEC 62899 specifies the method for determining accurate inkjet droplet volume based on images obtained by drop-in-flight measurement systems. It does not apply to imaging systems using interference fringes, such as holography or phase doppler anemometry. This document is not limited to drop-on-demand inkjet systems, but might not be applicable to continuous inkjet or liquid dispensing systems. This document includes a description of the issues concerning such measurements and consideration of the limits to measurement accuracy.