  We study the possibility of achieving low unification scale in a grand
unification scheme based on the gauge group SU(16). Baryon number symmetry
being an explicit local gauge symmetry here gauge boson mediated proton decay
is absent. We present in detail a number of symmetry breaking patterns and the
higgs field representations giving rise to the desired symmetry breakings and
identify one chain giving low energy unification. These higgs field
representations are constructed in such a way that higgs mediated proton decay
is absent. At the end we indicate the very rich low energy physics obtainable
from this model which includes quark-lepton un-unified symmetry and chiral
color symmetry. In brief some phenomenological implications are also studied.
