This part of ISO 289 specifies a method for determining the pre-vulcanization characteristics of compounded rubber. The pre-vulcanization characteristics determined by this method provide a means of estimating how long compounded rubber tan be maintained at high temperatures and remain processable. NOTE 1 No method of test tan be expected to correlate with all the different types of processing conditions such as are found in mixing, talendering, extrusion and moulding. Therefore it is necessary to consider previous experience with a particular process when interpreting the results.