1) Rubber fume is fume evolved in the mixing, milling and blending of natural rubber or synthetic elastomers, or of natural rubber and synthetic polymers combined with chemicals, and in the processes which convert the resultant blends into finished products or parts thereof, and including any inspection procedures where fume continues to be evolved.

2) The limit relates to cyclohexane soluble material determined by the method described in 'Rubber fume in air, measured as total particulates and cyclohexane soluble material'.

3) Rubber process dust is evolved during the manufacture of intermediates or articles from natural rubber and/or synthetic elastomers. This definition does not include dusts which, for occupational purposes, can be dealt with individually. In each case the relevant OEL will apply. Otherwise, where a substance with an OEL is present in a mixed dust, the OEL for that substance will apply, in addition to the rubber process dust limit.

4) Methods for personal sampling and measurement of total inhalable dusts are available in 'General method for the gravimetric determination of respirable and total inhalable dust' and 'Rubber fume in air measures as total particulates and cyclohexane soluble material'.