52 Pa. Code § 56.335
If a prior contact has not been made with a responsible adult occupant either at the residence of the customer, as required under § 56.334 (relating to procedures immediately prior to termination) or at the affected dwelling, the employee may not terminate service but shall conspicuously post a termination notice at the residence of the customer and the affected dwelling, advising that service will be disconnected not less than 48 hours from the time and date of posting.
52 Pa. Code § 56.335
This section cited in 52 Pa. Code § 56.261 (relating to billing frequency); 52 Pa. Code § 56.266 (relating to transfer of accounts); 52 Pa. Code § 56.331 (relating to general notice provisions and contents of termination notice); 52 Pa. Code § 56.340 (relating to winter termination procedures); 52 Pa. Code § 56.357 (relating to termination upon expiration of medical certification); 52 Pa. Code § 56.358 (relating to right of public utility to petition the Commission); and 52 Pa. Code § 56.393 (relating to termination pending resolution of the dispute).