Underground miners work in dangerous conditions, threatened by tunnel collapse, fires, and explosions. In 2006, three major coal mining accidents occurred, either from explosions or fire, and 19 miners died. As a result, Congress passed the Mine Improvement and New Emergency Response Act of 2006, more commonly known as the MINER Act. That law tasked the National Institute for Occupational Safety and Health (NIOSH) with researching and testing refuge alternatives in mines in the event of another disaster.

One of the main charges investigated by NIOSH’s Office of Mine Safety and Health Research was investigating the practicality, survivability, and cost of refuge alternatives, basically a secure area where miners can flee in the event of life-threatening accidents. The researchers found that built-in-place (BIP) and portable refuge alternatives were practical in most underground coal mines as a refuge of last resort, with BIP refuges a better option.