Normative and operative issue on the use of ULV

Droplet size sprayed by different models of foggers and knapsack mistblowers, adjusted to apply different volume rates, was measured using a laser diffraction instrument (Malvern Spraytec). Thanks to a dedicated software, for each equipment and setting tested, the instrument provided the droplets parameters used to characterize the sprayed droplets size (VMD or D50, D1, D90 and V100). Droplets sprayed by knapsack mistblowers resulted slightly coarser, with VMD ranging from 77 to 90. Concerning foggers tested (one cold fogger and one thermal fogger) results pointed out that ultra fine droplets were sprayed, featured by VMD values ranging between 37 and 78 micron according to the size of the dosing nozzles. The draft of test protocol for the inspection of foggers in use was prepared on the basis of elements available in EN ISO Standard and in analogue documents already prepared and used in some EU countries. The draft test protocol seems to be applied without problems for the inspection of this type of PAE in use.