THE ROLE OF THE IREQ INDEX IN THE DESIGN OF WORKING PRACTICES FOR COLD ENVIRONMENTS

For any cold environment a calculation can be made of the minimum clot hing insulation required by workers (IREQ). Two studies are reported w hich investigated the role of the IREQ index in the design of working practices for cold indoor environments. Both studies utilized the IREQ index within a Bow-chart design tool which aided the design of workin g practices within a cold environment. The first study used eight subj ects conducting light arm tasks at 2 degrees C within a laboratory the rmal chamber. The IREQ index calculated clothing ensemble was applied as an initial attempt at providing thermal comfort. All subjects exper ienced high levels of cold discomfort, primarily at the extremities. S ubsequent additions of local clothing adjustment enhanced the basic cl othing ensemble and greatly improved subject thermal comfort. An addit ional fixed period recovery allowance did not significantly improve su bjects' final thermal comfort vote. The second study was conducted wit hin an industrial cool store. The flow-chart design tool was rested in the industrial situation as a means of providing thermal comfort. As in the laboratory experiments, thermal comfort was not achieved solely with the application of an IREQ calculated clothing ensemble. By foll owing the Bow-chart procedure, thermal comfort was eventually achieved with local clothing adjustment. The two studies suggest that the use solely of the IREQ index as a working practice may not be adequate to provide thermal comfort. The IREQ index was suggested as adequate init ial protection against the strain induced on a worker from a cold envi ronment. The design tool included the IREQ index as an initial indicat or of cold stress; subsequent application of local clothing adjustment , followed by suitable general working practices were then required to achieve thermal comfort.