This part of ISO7494 specifies requirements and test methods concerning the configuration of dental unit connections to the compressed air supply, water supply, suction supply, and wastewater drain plumbing, the materials, design, and construction of the compressed air and water system within the dental unit, the quality for incoming water and air, and the performance of dental unit suction system. This part of ISO7494 also specifies requirements for instructions for use and technical description. This part of ISO7494 is limited to dental units that are not used for life support treatment of ambulatory patients or for oral surgery treatment requiring sterile air and water supplies. Amalgam separators are not included in this International Standard.