Volume One of these guidelines covers the principal portable (operator-carried) equipment: lever-operated knapsack, motorised knapsack, compression sprayer, mistblower and rotary atomizer. Vehicle-mounted and trailed field crop sprayers and orchard sprayers are covered in Volume Two. Volume Three covers portable (operator-carried) foggers.
Volume Four of the FAO guidelines covers locust and grasshopper sprayers - including portable sprayers (carried in the hands or on the back of the operator) and vehicle-mounted sprayers (fixed to the bed of a pick-up vehicle or small truck). It covers four principal types of sprayer:
RA - rotary atomizer
MB - motorised mistblower
VP - vehicle-mounted passive drift sprayer
VA - vehicle-mounted air-assisted sprayer
All of these are ULV sprayers i.e. they are designed to apply specialized ULV insecticide formulations undiluted, in volumes ranging from 0.3-3 litres/ha. These formulations are oil-based to reduce evaporation, and are atomized by the sprayer into small, evenly-sized droplets so that the wind can disperse them over a wide downwind swath. The independence from supplies of mixing water and the fact that the wide swaths allow a large track spacing and high work rate make them particularly suitable for rapid treatment of large locust and grasshopper targets in arid zones.
 Most locust and grasshopper
sprayers have rotary atomizers, but the term RA is used to describe portable
rotary atomiser sprayers and conform to terminology used in previous sprayer