1 Scope
This British Standard gives guidance on the interpretation of the results of petrographical
examination of coarse and fine aggregates, carried out in accordance with BS 812‑104, in terms of the susceptibility of the combined aggregate to alkali-silica reactivity
(ASR) sufficient to cause damage to concrete in which it is used. The guidance is
not applicable to alkali-carbonate reactive materials.
NOTE 1 Guidance on precision expected from the petrographical examination of coarse and fine
aggregates, carried out in accordance with BS 812‑104, is given in annex A.
NOTE 2 It is recommended that a petrographical examination be carried out by a petrographer
who is a member of the Proficiency Scheme for Aggregate Petrographers.