What is ICC 500: Five Things You Should Know

What is ICC 500: Five Things You Should Know

When we recently designed and manufactured the first-ever wood door and steel frame to meet the ICC 500 standard, we had to put our product through rigorous testing to ensure it could pass the ICC 500 test criteria. But what is ICC 500 and what does it take to meet the expansive criteria? Here are five things you need to know about ICC 500!

What is ICC?

The International Code Council (ICC) is an internationally recognized leading source of model codes and standards and building safety solutions that include product evaluation, accreditation, technology, training, and certification. Together, these solutions help ensure safe, affordable, and sustainable communities and buildings. The ICC has developed codes from all aspects of construction from the International Building Code and the International Green Construction Code to the International Plumbing Code and the International Swimming Pool and Spa Code. These codes are updated regularly to ensure they offer the latest in safety codes to people all around the world.

What is ICC 500?

A committee consisting of members of the National Storm Shelter Association (NSSA) and the International Code Council (ICC), formed in 2003, developed and released a standard to codify the design and construction of tornado and hurricane storm shelters. In 2008, the first ICC 500 was published and has been updated since then in 2014, with further updates in 2020. The ICC 500 code is intended to provide the minimum requirements for the design, construction, and installation of storm shelters used to protect occupants from high winds associated with hurricanes and tornadoes.

Where is ICC/NSSA Standard for the Design and Construction of Storm Shelters used?

Found in the 2009, 2012, and 2015 editions of the International Residential Code (IRC) and the International Building Code (IBC), ICC 500 dictates that a storm shelter should be built in certain buildings such as: 911 call stations, emergency operation centers, fire, rescue, and ambulance satiations, police stations, and K-12 school buildings with 50 or more occupants. Storm shelters should be built in these types of buildings if they are located in areas where the wind speed reaches up to 250 mph. Most of these locations are found in the southeast and the central United States where the wind speeds and frequency of tornadoes are high.

What testing is done in accordance with ICC 500?

Storm shelters and components of storm shelters must undergo and pass impact testing and static pressure testing. Numerous factors go into the actual testing procedure such as if the shelter is used for protection against hurricanes or tornadoes, the type of component under evaluation, the wind speed the shelter was designed to withstand, and the design of the component under testing. Impact testing is conducted on all components of the shelter with the only variables being the test missile’s weight and speed changing depending on the storm shelter’s design and wind speed. Static pressure testing is required for tornado and hurricane storm shelter components to a pressure differential of 1.2 times the design wind pressure. Cyclic pressure testing is only required for hurricane storm shelter components and is conducted using 4500 pressure cycles in the positive direction and 4500 cycles in the negative direction. Some components of storm shelters must also be fire-rated. To learn more about the testing process that went into our tornado wood door and steel frame, watch the video below.

Are wood doors compliant with ICC 500?

Our original Tornado Resistant Steel Doors and Frames were developed to meet the ICC 500 standard and the FEMA 316 standard and have been used in commercial storm shelters throughout the United States. After years of the specialized commercial door industry only offering steel door solutions for storm shelters, AMBICO began designing a Tornado Resistant Wood Door and Steel Frame solution to offer architects an alternative to steel. Manufactured in compliance with ICC 500, our Tornado Resistant Wood Doors and Steel Frames are tested to include multipoint hardware and are available in virtually every species, cut, and grade. They can be custom stain matched or clear coat finished while the hardwood stiles are coordinated to match face veneers. Our Tornado Resistant Wood Doors and Steel frames are supplied as they are tested with hardware and at the largest size so anything smaller is guaranteed compliant.

Rachel Barr, P.Eng
Design Engineer

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