This zone is formed by Mwanza, Geita, Shinyanga, Simiyu, Kagera and Mara regions and its main offices are in Mwanza along  the Station Road with a sub-office in Bukoba in Kagera Region. The zone is known by its notable economic activity around mining as it boasts of a handful ofbig mines and mining companies operating  in different regions in the zone. OSHA is highly concerned with the safety and health of workers in mining companies as well as of small and medium size miners. It thus ensures that all people working in mines and other sectors are in compliance with safety and health laws and regulations.