May 25, 2013 Radius Engineering offers a Twister Resister ND10 Storm Shelter. The ND10 Twister Resister shelter is a totally selfcontained 5 psi jumbo corrugated cylinder underground 586 FT3 storm shelter specifically designed to protect 10 people from F5 tornadoes, CAT 5 hurricanes, 8. 5 Richter earthquakes, and ground fires with a 2 day life support system.