ISO 16405:2015 gives guidance concerning suitable apparatus and procedures to be used when applying the FTIR method to measure concentrations of effluent gases produced in large-scale or simulated real-scale fire tests. Such tests include the room corner test (see ISO 9705) and open calorimeter tests as described in ISO 24473.

This guidance and measuring method only describes the way in which the sampling of the gases and collection of FTIR spectra are performed. Analysis of spectra and calibration is part of ISO 19702.