The Heubach test method was established in 2008 to measure free-floating dust from treated seeds. In this test, treated seeds are mechanically stressed over a defined period to measure the proportion of free-floating dust in the seed lot. With the help of a continuous operating airflow, free-floating dust abrasion particles are collected in a filter. The measured amount of dust can be applied to the amount of seed inserted. In the laboratory, the JKI applies the “JKI-Heubach-Method”. The manufacturer Heubachcolor originally used the equipment to measure abrasion of colors and varnish as well as pharmaceuticals and granules.
A regular seed sampling and Heubach testing is obligatory for seed treatment facilities listed by the JKI in Germany (“List of Seed treatment facilities with quality assurance systems for dust reduction”).
Oil seed rape
Frequency of Heubach tests: once a week
Frequency of Heubach tests: once a week, exception MESUROL: every seed is sampled and tested
Frequency of Heubach tests: once every two weeks
Frequency of Heubach tests: every 500t, at least three tests in a season
To achieve good seed quality it is crucial to do functional tests before the start of production. The formulation approval is given when the Heubach results are below the reference value. Below the reference values, which count in JKI-listed seed treatment facilities are listed for several crops:
Oil seed rape
Reference value: 0,5g/700.000 seeds
Reference value: 0,75g/100.000 seeds
Reference value: 0,25g/100.000 seeds
Reference value: 0,25g/ha
The dust collected during the Heubach test can afterwards be used to determine the active ingredient in the dust.