Außerdem fordert die WHO(5), daß das Qualitätssicherungsprogramm der technischen und physikalischen Aspekte die ###>It is further stated by the WHO(5) that the QA programme of the technical and physical aspects should include the specifications drawn up when the equipment is ordered, acceptance tests after the purchase of the equipment and the determination of a baseline standard, the initial calibration, periodic constancy checks and special tests after major repairs.