Division 2.6.4 F1F2F3
United Kingdom
The test shall be performed either in tubes or in microplates. The mixture of antigen and serum dilutions shall be incubated for 16- to 24-hours at 37 °C.
At least three dilutions must be prepared for each serum. Dilutions of suspect serum must be made in such a way that reading of the reaction at the positivity limit is made in the median tube (or well for the microplate method).