Recognizing this testing and labeling, specifications can request documentation certifying that the door assembly is compliant with the most current versions of FEMA’s safe room publications (FEMA P-361 and FEMA P-320) or ICC-500 for a tornado wind speed of 250 mph. Such labels specified for occupant protection should be issued by the agency that approved them to show basic information, including the name of the manufacturer plus performance characteristics, such as the test missile size and speed or test pressure. The commonly accepted practice is through labeling by third parties, such as Underwriters Laboratories (UL), Intertek Testing Services (ITS), or others. FEMA is not the entity that tests and certifies products, rather, the manufacturers of safe room door assemblies must obtain independent certification. When selecting and specifying such assemblies, architects need to be sure that components have been tested together specifically for a tornado safe room. In this case, the door assembly includes the door, hardware (locks and hinges), frame, and attachment devices used to anchor the door frame to the surrounding safe room wall. Impact test results on safe room doors show failure at the latch/lock (left), failure by full penetration (center), and a passing condition that withstood both penetration and latch/lock failure (right).įEMA points out that only door assemblies designed and tested to resist tornadoes can provide the needed life-safety protection for a safe room or shelter. Photos courtesy of FEMA Federal Insurance and Mitigation Administration Fact Sheet, September 2014 In other cases, the hardware can be damaged and fail, allowing the door to swing open and/or shut in the wind and bringing the unwanted weather inside the safe room. ![]() ![]() ![]() In some cases, the missile-like projectile can hit the door, penetrate all the way through, and either harm people inside or allow high winds to enter. Dramatic failures have occurred when such wind-borne debris (wood studs, metal posts, sign supports, etc.) have struck steel doors. While they might remain in place and closed in some high-wind conditions, they cannot withstand the impact of the wind-borne debris, or “missiles,” that a tornado can propel. There is a common misconception that a steel door marketed for storm protection with three locks and three hinges can provide the needed protection in tornadoes, but testing has demonstrated that they cannot. When careful selection and installation of the safe room door assembly is not part of the overall design, then the safe room door opening can leave occupants at great risk of injury or even death during high-wind events.Ĭontrary to some perceptions, ordinary steel doors used in residential and commercial construction are not appropriate for safe rooms. Just as the walls and roof of a safe room are designed and built to protect against extreme winds and wind-borne debris, so too, the whole door assembly (door, frame, and hardware) must be designed together to do the same. However, the room or building will only be as strong as its weakest part, which in some cases has proven to be the door leading into it. concrete, CMU, etc.) following the standards. ![]() The engineered construction of the walls, roof, and floor are fairly straightforward in terms of using substantial, reinforced materials (i.e. Residential and commercial buildings that incorporate safe rooms or shelters following ICC-500 or FEMA guidelines are becoming more popular, particularly among increasing urban populations seeking protection from violent tornadoes or hurricanes.
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