DIN EN ISO 11990-1:2011-11

A fire in the airway is always a serious matter. In addition to local damage in the larynx, injury can occur to the lower airway and the parenchymal tissue in the lung. The products of combustion can be blown into the lungs. Procedures performed in the airway where a tracheal tube and a laser are used bring together an oxygen enriched atmosphere, a fuel and high power, the three ingredients necessary to create a fire. The likelihood that a laser beam will contact the tracheal tube during airway procedures is high. In the early to mid-1980s, the increasing use of such lasers was followed by airway fires and, subsequently, the development of tracheal tubes designed specifically to be resistant to laser ignition and damage. Unfortunately, some of these tubes were not sufficiently resistant under operating room conditions, and airway fires continued to occur. These events led to the development of the test method described in this part of ISO 11990, in order to assist the clinician in determining which tracheal tube shaft is most laser-resistant for a defined set of conditions. This part of ISO 11990 specifies a method of testing the continuous wave (cw) resistance of the shaft of a tracheal tube designed to resist ignition by a laser. It is not applicable to other components of the system, such as the inflation system and cuff, which are defined in ISO 11990-2. The method specified in this part of ISO 11990 can be used to describe the properties of materials, products or assemblies in response to heat and flame under controlled laboratory conditions. It does not describe or appraise the fire hazard or fire risk of materials, products, or assemblies under actual clinical use conditions. However, the results of this test can be used as one element of a fire risk assessment which takes into account all factors pertinent to an assessment of the hazard of a particular end use. This standard has been prepared by the team in GAK 812.0.1 "Laser in der Medizin" ("Lasers in medicine") of the Optics and Precision Mechanics Standards Committee (NAFuO) and of the DKE (German Commission for Electrical, Electronic and Information Technologies) at DIN and VDE.