Are You Aware of ICC 500 Code Criteria Changes – 2020 Edition?

In parts of the US – tornadoes and hurricanes are an expected part of life. In fact, the United States sees more tornado and hurricane activity than any other place on the planet (National Centers for Environmental Information, n.d.) To combat these weather events, the Federal Emergency Management Agency (FEMA) in 1998 published FEMA P-320 – “Taking Shelter from the Storm – Building a Safe Room for Your Home or Small Business.” This document outlines the official standards for the design and construction of safe room storm shelters in the US. In 2000, FEMA published a follow-up document entitled FEMA P-361 – “Safe Rooms for Tornadoes and Hurricanes: Guidance for Community and Residential Safe Rooms” whereby community safe rooms are built for groups of 16 or more people. FEMA P-361 also sets the criteria for FEMA tornado shelter grants and outlines the standards for design, construction, and operation of storm safe rooms which include debris impact testing.


Committee Formed by ICC and NSSA

After years of post-disaster investigations into the performance of safe rooms and storm shelters, the International Code Council and the National Storm Shelter Association (NSSA) formed a national committee to develop a consensus standard to define the design and construction requirements of tornado and hurricane storm shelters. The standard developed was entitled ICC 500 and was initially published in the Summer of 2008 and subsequently updated in 2014. According to International Code Council, “The purpose of this standard is to establish minimum requirements to safeguard the public health, safety and general welfare relative to the design, construction, and installation of storm shelters constructed for protection from high winds associated with tornadoes and hurricanes”. Currently, the criteria are under review by the ICC Consensus Committee on Design and Construction of Storm Shelters and is expected to be published in 2020.

Once the review is completed, manufacturers of storm shelters and their associated components will refer to the ICC 500-2020 as the accepted standard. The standard gives the minimum requirements to safeguard safe room occupants from conditions commonly experienced during tornadoes and hurricanes. The ICC 500 code criteria is specifically referenced in the 2015 International Building Code (IBC) and the International Residential Code (IRC) as the governing standard for the construction and design of storm shelters. While changes to the code have not yet been officially published by ICC, The International Code Council, the NSSA warns that changes are imminent and that anyone associated with storm shelter design and construction prepares for these changes now.


Certification in Accordance with ICC 500

Although FEMA does not test or certify individual products or manufacturers of said products, they do require that manufacturers of storm shelter doors certify their products in accordance with ICC 500. Manufacturers of storm shelter doors will need a certification listing report for Authorities Having Jurisdiction during permit review. Companies wishing to become certified by obtaining a certification listing report can submit their testing data to a certification body, Like ICC-ES to determine if the data is sufficient to certify their products according to ICC 500. Should testing be necessary, a testing agency accredited in accordance with ISO/IEC 17025 to conduct missile impact and pressure testing should be utilized (like ICC-NTA). The testing agency can help to determine the process for testing, listing, and labeling storm shelters and storm shelter components.


What is needed for Storm Shelter Certifications?

Testing for storm shelters and storm shelter components is quite rigorous and is designed to replicate real-world conditions of extreme weather found during tornadoes and hurricanes. In November 2019, the National Storm Shelter Association held its Storm Shelter Conference in Birmingham, Alabama. The event featured technical sessions focused on significant changes to requirements surrounding design and construction.

Manufacturers of storm shelter and storm shelter components may already possess the appropriate test data and may be able to utilize the data to acquire the certification labels now required. When updated testing data is necessary, it is crucial that storm shelter and storm shelter door manufacturers choose a third-party company that has a deep understanding of the ICC 500 code criteria and, if needed, also has the proper equipment to test against missile impact, perforation, and pressure.


Highlights of Anticipated Requirements:

  • Look for changes in the code to outline requirements to have only engineered plans for use of a shelter. The manufacturer or constructor shall provide the test laboratory with applicable product specifications and drawings detailing materials of construction and applicable installation details.
  • All storm shelters must be designed for the impact of wind-borne debris in accordance with ICC 500 as laid out in the criteria. (Check out “NTA’s Test Wall and Impact Cannon: Bigger, Faster and Smarter” blog here)
  • Impact locations for double doors, rolling doors, and witness screens will be changed. The code will outline the speed of impact, a minimum number of impacts, and the location of impacts depending on the door style.
  • Doors must possess the appropriate listing and labeling signifying to Authorities Having Jurisdiction the manufacturer has been certified to ICC 500 criteria.
  • Shelters tested to tornado standards must undergo pressure and missile impact tests while hurricane shelters must undergo pressure, missile impact, and cycling tests.
  • Doors and their hardware and components must remain attached during the testing.
  • The anchor installation and foundation elements used during installation must withstand a specified load path from the roof to the ground.
  • Structures that are rated Educational Group E Occupancy, the shelters must be in compliance. Educational Group E Occupancy covers those shelters, among others, the use of a building or structure, or a portion thereof, by six or more persons at any one time for educational purposes through 12th grade. 


Learn more about ICC 500 testing standards here and certification here.


ICC NTA, LLC., a member of the Code Council Family of Solutions, is a respected third-party source for certifying and testing storm shelter doors. Manufacturers who need accurate information on testing and/or certifying to ICC 500 standards can rest assure that ICC NTA can provide accurate, timely, and reliable information. Further, ICC NTA is unique in that all services are done under one roof to include quality control manuals, code evaluation reports, test data evaluation, ongoing quality control surveillance, product testing, or simply an explanation for certification requirements. For more on this, call ICC NTA at 574-773-7975 or click here and request to be contacted by an ICC NTA representative.


“U.S. Tornado Climatology.” Retrieved from NOAA website, Accessed 22 Aug 2019.

FEMA Publications (all available for download from the FEMA Library at Some documents have multiple editions. The most current edition is listed as the year published, and older editions are noted in the reference.