At what droplet size does spray drift become a concern?

Spray drift is a significant consideration in aerial application, as it can lead to unintended pesticide distribution away from the targeted area, potentially harming non-target organisms, including crops, wildlife, and humans. The concern for spray drift typically arises at droplet sizes of 200 microns and smaller.

Droplets in this size range are small enough to be carried by the wind over distances, making it more difficult to control their flight path and ensuring they land on intended targets. The behavior of these smaller droplets is influenced by factors like air movement, which increases the likelihood of drift.

Understanding that droplets larger than 200 microns tend to settle more quickly and are less affected by wind helps in managing and mitigating drift. Those droplets are more likely to land where intended, thus reducing the risk of drift and the associated negative impacts. Therefore, maintaining droplet sizes above this threshold is a key practice for minimizing spray drift in aerial applications.