A supplier of diagnostic x-ray services furnished in a place or residence used as the patient's home or, in certain circumstances, in an institution, where the institution cannot bill for the services. Portable x-ray services include: skeletal films involving arms and legs, pelvis, vertebral column, and skull; chest films which do not involve the use of contrast media (except routine screening procedures and tests in connection with routine physical examinations); and abdominal films which do not involve the use of contrast media. Procedures and examinations which are excluded from portable x-ray services include the following: procedures involving fluoroscopy; procedures involving the use of contrast media; procedures requiring the administration of a substance to the patient or injection of a substance into the patient and/or special manipulation of the patient; procedures which require special medical skill or knowledge possessed by a doctor of medicine or doctor of osteopathy or which require that medical judgment be exercised; procedures requiring special technical competency and/or special equipment or materials; routine screening procedures; and procedures which are not of a diagnostic nature.