Environmental quenching efficiency as a function of radial distance from the cluster centres, measured in a single broad mass bin. We can do this because environmental quenching, at least in this regime, seems to be a process that is largely mass-independent (cf. Sect. 5.1). Dashed curve: same but increasing the quenched fraction in the field (cf. Eq. (4)) so that f_EQ is consistent with zero in the outermost bin.