An emergency services system (“ESS”) for a worksite is constituted by a number of tags, a mesh network, and a management system. Each person on the worksite is provided with a tag. Each tag when activated and logged onto the ESS uniquely identifies the person carrying that tag. The mesh network comprises a number of nodes and is arranged to provide communication over the entirety of the worksite. The nodes communicate with active tags. The management system receives and processes position data of active tags from the nodes via the communications network. The management system includes one or more displays arranged to display information pertaining to a worksite, its personnel and status. The ESS relies on use of signal strength in the mesh communication network to provide one source of location information. The observed signal strength received to multiple nodes is used to triangulate the position of a tag.