  Absorbing phase transition in restricted exclusion processes are
characterized by simple integer exponents. We show that this critical behaviour
flows to the directed percolation (DP) universality class when particle
conservation is broken suitably. The same transition, when studied using the
average density as the controlling parameter, yields critical exponents quite
different from DP; we argue that these exponents are actually related to DP by
a scaling factor $1/\beta_{DP}.$ These conclusions also apply to conserved
lattice gas in one dimension.
