  In this paper, we associate the idea of derivation languages with flat
splicing systems and compare the families of derivation languages (Szilard and
control languages) of these systems with the family of languages in Chomsky
hierarchy. We show that the family of Szilard languages of labeled flat finite
splicing systems of type $( m, n)$ (i.e., $SZLS_{n, FIN}^{m}$ ) and $REG$, $CF$
and $CS$ are incomparable. Also, it is decidable whether or not $SZ_{n,
FIN}^{m}(\mathscr{LS}) \subseteq R$ and $R \subseteq SZ_{n,
FIN}^{m}(\mathscr{LS})$ for any regular language $R$ and labeled flat finite
splicing system $\mathscr{LS}$. Also, any non-empty regular, non-empty
context-free and recursively enumerable language can be obtained as homomorphic
image of Szilard language of the labeled flat finite splicing systems of type
$(1, 2), (2, 2)$ and $(4, 2)$ respectively. We also introduce the idea of
control languages for labeled flat finite splicing systems and show that any
non-empty regular and context-free language can be obtained as a control
language of labeled flat finite splicing systems of type $(1,2)$ and $(2, 2)$
respectively. At the end, we show that any recursively enumerable language can
be obtained as a control language of labeled flat finite splicing systems of
type $(4,2)$ when $\lambda$-labeled rules are allowed.
