49 Pa. Code § 37.82
An individual, firm or corporation who has reason to believe that a professional engineer, professional land surveyor or professional geologist has engaged in gross negligence, incompetency or misconduct in the practice of engineering, land surveying or geology or has violated the act or this chapter, shall report the action to the Complaints Office of the Bureau of Professional and Occupational Affairs by telephoning the Complaints Office at 1 (800) 822-2113 or by submitting a written complaint to the Complaints Officer of the Bureau of Professional and Occupational Affairs, Post Office Box 2649, Harrisburg, Pennsylvania 17105-2649, charging the professional engineer, professional land surveyor or professional geologist with a violation of the act, and specifying the grounds upon which the complaint is based.
49 Pa. Code § 37.82