'The European Standards for Asphalt' was the title of John Bradshaw-Bullock's presentation to a joint technical evening for the Institute of Quarrying and Institute of Asphalt Western Branches on the 8th February.

The European Standards for Asphalt follow the introduction of the standards for aggregates in 2004 and are intended to harmonise asphalt materials across Europe and thereby eliminate barriers to trade.

The standards, which are designated as EN 13108, are comprised of parts 1 to 7 which cover individual material types and part 8 which relates to the properties of reclaimed asphalt product when used as a constituent of asphalt materials. Also covered are parts 20, which relates to the Type Testing requirements of materials and part 21 which covers the requirements of Factory Production Control.

There are a number of key differences to note between the new standards for asphalt and the current British Standards, which include:

The requirement to evidence product conformity by CE marking materials.
The binder and filler contents in material test results will not be adjusted when reporting - the use of correction factors will no longer be permitted and results will be presented differently to the current format.
Binder contents in material mixes will be determined by a calculation relating to the density of the aggregates.
The method of describing materials will revert to the former reference to the nominal size i.e. 14 as opposed to 0/14.
The use of the aggregate PSV in the material description is not mandatory under the EN standards, however this practice should continue in the UK.
The specification tolerances will not be found in the individual product standards, these are instead listed in part 21.
For a CE marked material, the Type Testing is completed on specific constituents which cannot be altered e.g. specific aggregate source, although the mix is not plant specific.

Critical to the interpretation of the European Asphalt Standards will be the document PD 6691. This Published Document will be produced by the BSI and will provide guidance on the use and application of the new standards in the UK. The PD will follow a similar format to the documents published as guidance to the EN aggregate specifications. When used in conjunction with EN 13108 the PD will provide the specification requirements for the material mixtures that are applicable to the UK. Included in the PD is Annex A, which covers the mixture specifications for Asphaltic Concrete, Hot Rolled Asphalt including Pre-Coated Chippings and Stone Mastic Asphalt materials. In Annex B the PD covers the evaluation of conformity and the requirements for Type Testing of materials and Factory Production Control.

The requirements for the testing of asphalt materials are now covered under the European Standards EN 12697, and the BSI have also published guidance document PD 6692 to help apply the test standards in the UK.

The former 'part 2' documents in the British Standards 4987 and 594 which dealt with the specification for transport, laying and compaction of asphalt materials have also be revised to complement the new European Asphalt Standards which only cover material production. The new document titled BS 594987 will provide familiar details of the requirements for compaction and compacted thickness for the materials detailed in the new EN 13108 standards as well as a series of annexes providing the procedures for designing materials according to the
Specification for Highway Works 900 series.

Photo: Andy Shakeshaft(IOQ Chairman West of England), John Bradshaw-Bullock, Graham Bishop(IAT Chairman West of England)

Photo (left to right)- Andy Shakeshaft(IOQ Chairman West of England), John Bradshaw-Bullock, Graham Bishop(IAT Chairman West of England)

With 11 months left to implement the standards in the UK it is clear that there is a great deal of work to be done to ensure appropriate training and awareness of the standards for all personnel involved in the production and supply of asphalt materials, and for customers and specifiers before the equivalent British Standards are withdrawn in March 2008. The publication of documents BS 594987 and PD 6691 are expected in April/May 2007.

Finally a vote of thanks was given by Andy Shakeshaft, Chairman of the West of England Branch, IOQ

Eloise Meyer (West of England Branch Committee member)