Occupational safety should be seen as an investment for companies, because although it doesn't generate profits, it does prevent losses. Regulatory standards NR 15 and NBR 5413 (Brasil, 2008) stipulate that ergonomic, physical and chemical risks should be minimized in the workplace, thus reducing the risk of accidents. The aim of this study was to assess environmental factors such as noise, illuminance, temperature and humidity in a rolling mill located in the Zona da Mata region of the state of Rondônia. In order to assess the company, questionnaires were carried out to get a diagnosis of the employees in terms of age, length of time with the company, schooling, among others. A multi-parameter ITMP 600 meter was used to measure noise and illuminance, and a portable digital globe thermometer ITWG 2000 for temperature and humidity. The measurements were carried out during the 1pm shift, close to the employees who were carrying out their duties in each sector. The values obtained for average noise and impacts were below those permitted by NR 15, while the temperature and humidity levels were above, although the climate in the region is classified as hot and humid,