Thermal comfort in Supermarket's refrigerated areas: An integrated survey in central Italy

Thermal comfort conditions in supermarkets have been barely investigated in the past and only few meaningful studies have been carried out involving customers and staff. In this paper, the results of an integrated investigation on thermal conditions of customers and staff in refrigerated areas of four supermarkets in Central Italy are presented and discussed. Microclimatic surveys demonstrated that thermal comfort conditions for staff were generally consistent with ISO 7730 requirements. To the contrary, considering worn clothes, the thermal sensation predicted for customers was generally turned towards the cold both in autumn and summer with PMV values often below −2. The analysis of the local microclimatic parameters revealed low floor temperatures and a meaningful cold air stratification characterized by air temperature vertical differences measured between head and ankles up to 8–9 °C in case of open cabinets. In summer, due to the lower air temperature values (compared to the outdoor) combined with the usual low thermal insulation of clothes, the thermal environment is cold and the IREQ model revealed dangerous conditions for customers in three of the investigated areas with DLE (Duration Limit of Exposure) of about 40 min. In autumn, DLEs largely exceeded 1 h. Results of the subjective investigation carried out in two sales points for 35 customers were consistent with the objective survey and revealed higher percentages of dissatisfied in case of women. Finally, local discomfort due to cold feet effect seemed to be more consistent for women due to the low clothing distribution in lower parts of the body.