  In the standard Friedmann-Lemaitre-Robertson-Walker (FLRW) cosmological
model, the energy conditions provides model-independent bounds on the behavior
of the distance modulus. However, this method can not provide us the detailed
information about the violation between the energy conditions and the
observation. In this paper, we present an extended analysis of the energy
conditions based upon the entropy density of the universe. On the one hand, we
find that these conditions imply that entropy density s depends on Hubble
parameter H(z). On the other hand, we compare the theoretical entropy density
from the conservation law of energy-momentum tensor with that from the energy
conditions using the observational Hubble parameter. When we consider a FLRW
universe, according to the theoretical prediction, OHD, thermodynamics and
several independent cosmological probes, show that the dominant energy
condition is fitter than other energy conditions.
