(a) General rule.--A holder of a volunteer license who, in good faith, renders professional health care services within his scope of practice under this act shall not be liable for civil damages arising as a result of any act or omission in the rendering of care unless the conduct of the volunteer licensee falls substantially below professional standards which are generally practiced and accepted in the community and unless it is shown that the volunteer licensee did an act or omitted the doing of an act which the person was under a recognized duty to a patient to do, knowing or having reason to know that the act or omission created a substantial risk of actual harm to the patient.