Division 2.5.3 F1F2F3

The RBT shall be carried out in the following manner:

1. (a)

   serum (20-30 μl) is mixed with an equal volume of antigen on a white tile or enamel plate to produce a zone approximately 2 cm in diameter. The mixture is rocked gently for four minutes at ambient temperature, and then observed in a good light for agglutination;

2. (b)

   an automated method may be used but must be at least as sensitive and accurate as the manual method.