DIN EN ISO 16954:2015-11

This International Standard provides type test methods for evaluating the effectiveness of treatment methods intended to prevent or inhibit the formation of biofilm or to remove biofilm present in dental unit procedural water delivery systems under laboratory conditions. This International Standard does not apply to devices intended to deliver sterile procedural water or sterile solution. It also does not apply to lines, tubing, or hoses that deliver compressed air within the dental unit. This International Standard does not establish specific upper limits for bacterial contamination or describe test methods to be used in clinical situations. It also does not establish test methods for evaluating any deleterious side effects potentially caused by treatment methods. The test methods provided in this International Standard can be used to test other dental equipment that delivers non-sterile water to the oral cavity. The committee responsible for this standard is Working Group NA 014-00-05-05 AK "Wasser und Luft" ("Water and air") of Working Committee NA 014-00-05 AA "Zahnärztliche Ausrüstung" ("Dental equipment") of at DIN Standards Committee Dentistry. For inoculation of the test water to produce the biofilm, solutions with the following two bacteria were determined: 1. Pseudomonas aeruginosa (PA); 2. Klebsiella pneumonia. Since Klebsiella has symbiotic effects with PA, these effects shall be taken into account when growing the biofilm. The gram-negative bacteria PA are mainly found in humid environments such as showers and tap water; they can attack the lungs as well as the intestinal tract and skin. PA is resistant to many disinfectants and is therefore a well-known hospital germ. In the outer membrane PA carries the lectin LecA, which causes adhesion and biofilm formation.