Downwind Spray Drift Buffer
A relative downwind no-spray buffer that scales an editable droplet-class base by wind speed and release height.
Example
You enter
- Droplet class medium
- Wind speed (mph) 15
- Release height (in) 30
- Reference height (in) 20
You get
- Recommended downwind buffer 45
Details, formula, and sources
A planning aid only -- the product label's mandatory buffer is the law (FIFRA); your state lead agency governs.
Buffer = base buffer x (wind / 10 mph) x (release height / reference height). Base buffer set by droplet class: Very Coarse 5, Coarse 10, Medium 20, Fine 40 ft (editable, representative).
USDA / land-grant extension drift-management guidance; EPA pesticide label and the Worker Protection Standard (40 CFR 170), by name.
Extension drift-management guidance free on land-grant university extension sites. The label ships with the product.
Read and follow the product label. The label is the law (FIFRA).
Field names used by the API: droplet_class, wind_mph, boom_height_in, ref_height_in, buffer_ft
- Droplet-class base buffers 5 / 10 / 20 / 40 ft for Very Coarse / Coarse / Medium / Fine at the 10 mph, 20 in reference; editableextension drift-management guidance
- Label governs do not spray toward a sensitive area, during a temperature inversion, or above the label's maximum wind speed; coarser droplets and a lower boom cut drift far more than any bufferEPA label / WPS 40 CFR 170