No signs are required other than those specified elsewhere in §§ 7.421-7.432 if attendants and conductors are placed as specified. Signs, if used, should be short, simple, bold in design, and to the point.
34 Pa. Code § 7.431
This section cited in 34 Pa. Code § 7.421 (relating to definitions) and 34 Pa. Code § 7.422 (relating to applicability).