  In this article, we consider time-inhomogeneous diffusive particle systems,
whose particles jump from the boundary of a bounded open subset of $\R^d$,
$d\geq 1$. We give a sufficient criterion for the family of empirical
distributions of such systems to be uniformly tight, independently of the jump
location of the particles. As an application, we show that the conditional
distribution of a family of time-inhomogeneous and environment-dependent
diffusions conditioned not to hit the boundary of a bounded open subset of
$\R^d$ is uniformly tight.
