This European Standard specifies the procedure for determining the passing ability (measured by the blocking step), the flow spread and t500J flow time of self-compacting concrete as the concrete flows through the J-ring. The test is not suitable when the maximum size of aggregate exceeds 40 mm. NOTE In respect to the relationship between aggregate size and bar spacing, the test is intended to assess the passing ability of the concrete proposed with the bar spacing typically in the works. If the concrete blocks then the aggregate size could be too large for the particular application.