  We study the nonequilibrium critical point of the zero temperature random
field Ising model on a triangular lattice and compare it with known results on
honeycomb, square, and simple cubic lattices. We suggest that the coordination
number of the lattice rather than its dimension plays the key role in
determining the universality class of the nonequilibrium critical behavior.
This is discussed in the context of numerical evidence that equilibrium and
nonequilibrium critical points of the zero-temperature random field Ising model
belong to the same universality class. The physics of this curious result is
not fully understood.
