In order to reduce the chances of vapor drift, the labels of volatile pesticides advise against applying the products when air temperatures are at or above ____°F.

• A. 70
• B. 75
• C. 80
• D. 85

Answer: (B)

Pavlor drift becomes more likely as temperatures rise because a pesticide’s vapor pressure increases and air movement can carry more vapor away from the target area. To minimize drift, labels set a temperature threshold and advise against applying when temperatures reach or exceed that point. For this topic, that threshold is 75°F, so applying at or above 75°F raises the drift risk and is discouraged. The other numbers would either be more restrictive or less protective than this standard guidance, which is why 75°F is the best choice.