49 C.F.R. § 213.205 – Derails.

(a) Each derail shall be clearly visible.
(b) When in a locked position, a derail shall be free of lost motion which would prevent it from performing its intended function.
(c) Each derail shall be maintained to function as intended.
(d) Each derail shall be properly installed for the rail to which it is applied. (This paragraph (d) is applicable September 21, 1999.)