Notes on the implementation of the IREQ model for the assessment of extreme cold environments

This paper has been entirely devoted to the difficulties that practitioners, skilled ergonomists or occupational health experts could find in the assessment of cold environments by means of IREQ model at the base of the ISO 11079 Standard. The in-depth analysis here discussed has underlined several difficulties about: a) the graphical calculation of the predicted limit exposures, DLE; b) some differences in both IREQ and DLE values reported for the cases of study; c) several errors or inconsistencies in the source code available on line for the assessment of DLEs. These occurrences lead to the systematic overestimation of the duration limit exposure that exceed up to four hours those obtained by means of the figures reported in the Standard with the consequent unreliable as-sessment. Such matters justify the need promote in the whole scientific community involved in the ergonomics of the thermal environment an in-depth discussion on the best practice to be followed for the assessment of extreme cold environments by means of IREQ model.