TNO has designed two types of labels to show the performance of tested tool systems and dust extractors; the hour label and the A/B/C/D-label. There are legal rules for the use of labels by third parties.
A test of a complete system (tool, extraction-accesory, suction hose and dust extractor) results in an hour label which indicates how many hours per eight-hour working day the system can be used, without exceeding the limit in the employees breathing zone.
The hour label does not give information about a single hand tool or dust extractor and should therefore never be used to indicate the performance of a single machine.
When only publishing an hour label for a tool system many information, which is required to obtain the label, is lost. This is for example essentail information on material used during the test, the diameter of the used suction hose, production during the test (number of drilling holes, meters grinded or sawed material). The hour label cannot be interpreted correctly without this information.
It is therefore not allowed to publish only an hour label for a hand-tool, dust extractor or combination of both. The hour label can only be published as a part of the TNO Newsletter which is made for each tested tool system.
An A/B/C/D-label is designed to compare the performance of dust extractors. Information about this label and its interpretation can be found on the page dust extractor classification.
In contrary to the hour label, the A/B/C/D-label can used in combination with a single product (dust extractor). Only the A/B/C/D-label is not sufficient to compare dust extractors. Also the hour label is important. Since essential information can't be captured in a label, TNO requires that a reference is made to this website when using the A/B/C/D-label. The image below represents the label how it should be used in practice. Any other form is not allowed. The labels can be downloaded at the bottom of the page.