A new ASTM International standard, E2872, Guide for Determining Cross-Section Averaged Characteristics of a Spray Using Laser-Diffraction Instruments in a Wind Tunnel Apparatus, will be used to guide characterization of nozzles and atomizers using laser diffraction instruments. E2872 is primarily applicable to aerial agricultural spraying, aerial forest sprays and air-blast spraying.
“Aerial spraying of pesticides is an essential element of forest management and food production,” says ASTM member Gordon Holloway, Ph.D., professor of mechanical engineering at the University of New Brunswick. “Spray efficacy and the reduction of environmental loading are important objectives of this approach, and they both depend on accurate spray characterization.”
The new guide describes tests specifically relating to the use of laser diffraction instrumentation to estimate the droplet size distribution for liquid sprays released into moving air streams.
Primary users of E2872 will be nozzle and atomizer manufacturers, chemical companies developing adjuvants, applicators calibrating equipment and regulators who require that sprays be accurately characterized before use.
E2872 was developed by Subcommittee E29.02 on Non-Sieving Methods, part of ASTM International Committee E29 on Particle and Spray Characterization. Now that E2872 has been approved, the subcommittee would be interested in having different laboratories apply the standard to particular test problems and share their resulting data and experience.