A method for the assessment under standard conditions of the output of dichlorvos slow-release units used for insect control.

A test method is described for the measurement, under standard conditions, of the amount of dichlorvos (00-dimethyl 2,2-dichlorovinyl phosphate) vapour emitted from insecticide slow-release units. Specimen results, obtained under these conditions, are given for the outputs of several types of unit during the initial 14-d period when output is greatest, with corresponding values for the concentration of dichlorvos in the air in a 28-m3 room where constant temperature and humidity are maintained. The relationship between unit output and the concentration developed in the air under various environmental conditions is discussed and the application of the method in the comparative assessment of the potential safety in use of different types of unit is proposed.