An article of footwear, such as a work shoe, is worn by miners. The footwear includes a location determining module which is able to locate its position by means of the timing and data contained in signals sent by it to locator devices which are placed at known locations throughout the mine, and which respond to transmissions made by the locator module. The footwear also contains a low frequency RF module which enables it to selectively transmit an alarm signal encoded with its location upon the selective activation by the wearer. In various embodiments, the invention can include sensors which are able to monitor physiological data of the wearer or the survivability of the ambient conditions where the footwear is located. Embodiments of the invention also provide the wearer with two-way communications capability. The various electronic components of the invention, can be formed in as a flexible modular unit which can be attached to existing footwear, or formed to new footwear during the manufacturing process, or thereafter.