The heat stress for workers employed in a dairy farm

Abstract

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 (<em>Grana Padano</em> cheese, string cheese, Parmesan cheese, etc.), while the cheese from buffalo’s milk (especially string cheese such as <em>mozzarella</em>) 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 are not comfortable for the workers 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 (clothing thermal insulation and the energy expenditure required from the work done by employees). Subsequently, main indices of heat stress assessment provided by the main technical standards were calculated. In particular have been calculated predicted mean vote and predicted percentage of dissatisfied in moderate thermal environments (environments in which the objective, in the design and management phases, is to achieve the thermal comfort), provided by the UNI EN ISO 7730 and the wet bulb globe temperature in severe hot environments (environments in which you must protect the health of workers) required by UNI EN ISO 27243. The results show some phases of risk from heat stress especially during times of test in which the internal air temperature exceeds the threshold of 30°C and possible solutions to improve the safety of the operators.