Presence of tar

Presence of tar

Whether part of an intended recycling scheme or for disposal purposes it may be required to identify the presence of tar in a pavement core.  As part of the logging procedure bituminous layers  are sprayed with ‘PAK marker spray’ which gives an indication as to the presence of tar within the material by identifying elevated PAH (polyaromatic hydrocarbon) levels.  In order to confirm the presence of tar when PAK testing gives a positive result, ADEPT (formerly the County Surveyors Society) in their document ‘Road Materials Containing Tar’  state thresholds for Benzo (a) pyrene, remaining components of a PAH17 suite and phenol leachate above which it may be assumed tar is present.

PAH (polyaromatic hydrocarbon) testing is undertaken by Nicholls Colton Group’s fully equipped *UKAS accredited testing laboratory No. 0320 and *MCERTS accredited laboratory which can undertake a wide range of materials testing.