Environmental changes affect human-beings' quality life style concerning their safety and comfort. Thus, nowadays there are many studies focused in inner/outer spaces improvement in order to ensure their occupants safety, comfort and health. Comfort conditions must be required in workplaces to achieve highest performance results, as the individuals spend most of their time in these spaces. The present work aims to study workers' thermal sensation regarding a case-study carried out in a glass industry in Marinha Grande, Portugal. Thus, a set of thermohygrometric data were collected to define the thermal pattern of the industrial space in study. In this sense, two indexes were used, EsConTer and PPD, purposing the thermal sensation pattern in the industrial space. This study results showed, clearly, the industrial space thermal pattern as well as the workers predicted thermal sensation. Moreover, it helped the Safety and Hygiene Department towards adopting strategic measures which improve workers' performances and their work satisfaction.