67 Pa. Code § 214.4 – Traffic signs.

(a) Proper sign installations. Signs shall be installed as follows:
1. (1) Sign (W35-1), SAFETY CORRIDOR—FINES DOUBLED NEXT XX MILES, shall be installed as close as practical to the beginning of the highway safety corridor and after each interchange along the corridor.
2. (2) Sign (W35-2), END FINES DOUBLED CORRIDOR, shall be installed immediately at the end of each highway safety corridor.
(b) Sign standards. Signs W35-1 and W35-2 shall be manufactured in accordance with the standards set forth in Appendix A for these signs.