Comparison of Legal Inspection Methods for used Field Sprayers in the Light of the Consequences

Abstract

The aim of our research was to confirm or refute the following hypothesis. There are commercial size, suspended and towed sprayers with hydraulic droplet nozzles capable of producing a uniform spray curtain over their full working width, which, if subjected to a fully compliant inspection procedure as described in the relevant legislation, can be certified as either 'passed' or 'not passed' by the inspection station carrying out the inspection. The result of the certification depends on the legal and standard test method used by the station to determine the transverse distribution.
In the light of our test results, we have found that the compliance of the results with the relevant standard may be affected by which of the two legal and standard methods is used to determine the transverse distribution, as one method is used only for inappropriate results, while the other method always gives acceptable results.
Our main conclusion is that monitoring stations with inspection authority may wittingly or unwittingly influence the outcome of inspections depending on which method is used to test the cross-sectional distribution. They are free to make their own decision in this respect. In our view, this type of discretion is not permissible for an activity with legal consequences.
It is recommended that the described experiments be continued to increase representativeness and that the horizontal trough-line method be made mandatory for authorised inspectors to determine the transverse distribution. This requires a inspection site where it can be ensured that precipitation does not influence the results of the technical examination and where wind speeds below the maximum permissible wind speeds defined in the relevant Ministry of Agriculture and Rural Development regulation are guaranteed at all times (e.g. a closed, draught-free hall).