40 Pa. Stat. § 859
When the inspector aforesaid shall withhold or withdraw a certificate of inspection, by reason of the incompetence or unreliability of the engineer, as provided for in this act and in the city ordinance for the inspection of steam boilers, or whenever he may consider the boiler or boilers unsafe, he shall give to the user of the boiler or boilers, and the insurance company issuing the policy thereon, written notice of the same, which notice shall contain a statement of the reasons for such action; this statement to be made, as aforesaid, shall be equivalent to the removal of the certificate, and in case the said boiler or boilers are insured, the withdrawal of the certificate, as provided for, shall render the policy of insurance upon all boilers to which said certificate had reference, void and of no effect: Provided, That nothing herein contained shall affect any policy of insurance now in force until its expiration, which shall not exceed three years from the date thereof, except for violation of article seventh, section two.
40 P.S. § 859