  Starting from a previously collected set of tachyon-free closed strings, we
search for N=2 minimal model orientifold spectra which contain the standard
model and are free of tachyons and tadpoles at lowest order. For each class of
tachyon-free closed strings -- bulk supersymmetry, automorphism invariants or
Klein bottle projection -- we do indeed find non-supersymmetric and tachyon
free chiral brane configurations that contain the standard model. However, a
tadpole-cancelling hidden sector could only be found in the case of bulk
supersymmetry. Although about half of the examples we have found make use of
branes that break the bulk space-time supersymmetry, the resulting massless
open string spectra are nevertheless supersymmetric in all cases. Dropping the
requirement that the standard model be contained in the spectrum, we find
chiral tachyon and tadpole-free solutions in all three cases, although in the
case of bulk supersymmetry all massless spectra are supersymmetric. In the
other two cases we find truly non-supersymmetric spectra, but a large fraction
of them are nevertheless partly or fully supersymmetric at the massless level.
