ISO 11140-4:2007规定了2级指示剂的性能，该指示剂可作为包装保健品（仪器等和多孔负载）蒸汽灭菌器的Bowie和Dick型试验的替代品。 符合ISO 11140-4:2007的指示器包含一种用作试验负载的指定材料。该测试负载可以重复使用，也可以不重复使用。ISO 11140-4:2007未规定试验荷载的要求，但规定了指示器的性能以及预期使用的试验荷载。ISO 11140-4:2007中规定的指示器旨在识别蒸汽渗透不良，但不一定指示蒸汽渗透不良的原因。 ISO 11140的本部分- 4:2007不包括确定这些指示器是否适用于空气去除阶段不包括在大气压力下排空的灭菌器的试验方法。

ISO 11140-4:2007 specifies the performance for a Class 2 indicator to be used as an alternative to the Bowie and Dick-type test for steam sterilizers for wrapped health care goods (instruments, etc. and porous loads). An indicator complying with ISO 11140-4:2007 incorporates a specified material which is used as a test load. This test load may, or may not, be re-usable. ISO 11140-4:2007 does not specify requirements for the test load, but specifies the performance of the indicator in combination with the test load with which it is intended to be used. The indicator specified in ISO 11140-4:2007 is intended to identify poor steam penetration but does not necessarily indicate the cause of this poor steam penetration. This part of ISO 11140-4:2007 does not include test methods to establish the suitability of these indicators for use in sterilizers in which the air removal stage does not include evacuation below atmospheric pressure.