An intercomparison using two popular survey meters was arranged to assess the ability of participants to test surface contamination monitors in compliance with the requirements of the Ionising Radiations Regulations 1985. The instruments were circulated and the data returned were compared with the NRPB values. The major inconsistencies were caused by differences in the interpretation of what constitutes 1 Bq of and in the conversion of the emission rate from plaques into a value of equivalent activity.