Which of the following statements is true regarding ULV-dispensing equipment?

The statement regarding ULV (Ultra-Low Volume) dispensing equipment being that it must be calibrated to produce specified droplet sizes is true because calibration is essential for ensuring that the equipment delivers the correct droplet size for effective application of pesticides. The effectiveness of the pesticide depends heavily on the size of the droplets produced; too large or too small droplets can lead to inefficient coverage, drift, or evaporation, diminishing the impact of the product being used.

Proper calibration guarantees that the appropriate amount of product is applied in a manner that maximizes efficacy while minimizing waste and potential environmental impact. This is particularly vital in public health pest control, where accurate dosing can significantly affect the outcome of pest management strategies.

The other statements do not accurately describe the functions or requirements associated with ULV dispensers. For instance, stating that it does not require calibration is misleading, as calibration is critical for precision. The implication that ULV equipment is designed for only liquid insecticides is inaccurate, as it can also be utilized for other liquid formulations. Lastly, saying it is only needed for thermal fogging is incorrect; ULV is a standalone application method that operates independently from thermal fogging technologies.