Here I compare the refmult distributions for fast offline from 3 triggers:
550007:  zdce_TOF0
550011: bbc_tac_TOF0
550018: bbc_tac_TOF0_hlt
All are on |vz|<30 cm, vr<2 cm from fast offline tracking.
Decided to do it on refmult rather than tofmult because of the large asymmetry in pseudorapidity of the multiplicity distribution,
combined with the vertex z range.  TOFmult can't make a fiducial cut to avoid this, so there remains a residual dependence of |tofmult| on vz just from the asymmetry of the distribution in pseudorapidity, but refmult at |eta|<0.5 is always fully enclosed
within the TPC for |vz|<30 cm and so the <refmult> is essentially flat.  Looks like the BBC is relatively more efficient in peripheral events than the ZDC, which I didn't expect.  Note that in all cases I have multiplied the distributions by the prescale of the trigger.