Spray drift potential evaluation of typical nozzles under wind tunnel conditions

According to the guidelines for plant protection equipment tests established by the German Federal Biological Research Centre for Agriculture and Forestry(BBA), measurements of the drift potential under different wind tunnel conditions(spray pressure, wind speed, temperature and relative humidity) were made for five typical nozzles. A Drift Potential Index(DIX) was calculated from parameters of vertical drift concentration in a section 2 m downwind from the nozzle. This is a practical and easy method to evaluate the driftability of the sprays. The results show that the drift potential decreases with increasing nozzle size and that there is a great influence of the droplet size and wind velocity on the drift potential.