ISO 11990-1:2011 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 11990-2:2010. ISO 11990-1:2011 can be used to measure and 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.