The heat stress for workers employed in a dairy farm

The italian dairy production is characterized by high heterogeneity. The typology quantitatively more important (80% of national production) is represented by cow’s milk cheeses (Grana Padano cheese, string cheese, Parmesan cheese, etc.),while the cheese from buffalo’s milk (especially string cheese such as mozzarella ) and cheese from sheep and goats represents respectively 4% and 8% of the national dairy production, and are linked to specific regional contexts. Some phases of the cycle of milk processing occur at certain temperatures that not are comfortable for the operator also in relation to possible problems due to thermal shock. The aim of this study was to evaluate the risk of heat stress on workers operating in a dairy for processing of buffalo milk. The research was conducted at a dairy farm located in the province of Viterbo, Italy, during the spring-summer period. To carry out the research were detected major climatic parameters (air temperature, relative humidity, mean radiant temperature, air velocity) and the main parameters of the individual operators (thermal insulation provided by clothing and the energy expenditure required from the work done by employees in the work areas investigated). Subsequently were calculated main indices of heat stress assessment provided by the main technical standards. In particular have been calculated Predicted Mean Vote (PMV) and Predicted Percentage of Dissatisfied (PPD) in moderate environments, provided by the UNI EN ISO 7730 and the wet bulb globe temperature (WBGT) in severe hot environments required by UNI EN 27243. The results show some phases of risk from heat stress and possible solutions to improve the safety of the operators.