Are calm winds always considered safe for application?

Calm winds are not always considered safe for application, primarily due to the potential risk of temperature inversions. Under certain atmospheric conditions, particularly when winds are light or calm, temperature inversions can occur. An inversion happens when a layer of warm air traps cooler air at the surface, which can prevent the dispersion of airborne chemicals or pesticides. This climatic phenomenon can lead to the accumulation of concentrated pesticides in certain areas, increasing the risk of drift to unintended locations or damaging sensitive ecosystems.

While calm winds might seem beneficial in minimizing immediate drift, the presence of an inversion can exacerbate problems related to pesticide application, leading to greater hazards than those posed by windier conditions. Thus, safety in application depends not just on wind speed, but also on a thorough understanding of environmental factors, especially temperature inversions.