  We study the regularization of an oriented 1-foliation $\mathcal{F}$ on $M
\setminus \Sigma$ where $M$ is a smooth manifold and $\Sigma \subset M$ is a
closed subset, which can be interpreted as the discontinuity locus of
$\mathcal{F}$. In the spirit of Filippov's work, we define a sliding and sewing
dynamics on the discontinuity locus $\Sigma$ as some sort of limit of the
dynamics of a nearby smooth 1-foliation and obtain conditions to identify
whether a point belongs to the sliding or sewing regions.
