Community Tornado Shelters



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Community Tornado Shelters
For more detailed guidance refer to;

FEMA 361, Design and Construction Guidance for Community Shelters



Available online at: http://www.fema.gov/library/viewRecord.do?id=1657
The purpose of document is to provide community shelter owners with guidance and items to consider when determining and planning for your shelter needs and use. It does not address specific design criteria to meet FEMA 361 requirements; the actual design should be accomplished by a qualified professional A&E. Items addressed below are excerpts from FEMA 361.
Community Shelters for Neighborhoods
Community shelters intended to provide protection for the residents of neighborhoods require designers to focus on a number of issues in addition to structural design, including ownership, rules for admission, pets, parking, ensuring user access while preventing unauthorized use, and liability. FEMA post-disaster investigations have revealed issues that need to be addressed in the planning of such community shelters. Many of these issues are addressed in the sample Shelter Operations Plans in FEMA 361, Chapter 9 and Appendix C for community shelters. The following are additional considerations;
Access and Entry. Confusion has occurred during past tornado events when residents evacuated their homes to go to a community shelter but could not get in. During the Midwest tornadoes of May 3, 1999, residents in a Wichita community went to their assigned shelter only to find it locked. Eventually, the shelter was opened prior to the event, but had there been less warning time for the residents, loss of life could have occurred. The Shelter Operations Plan should clearly state who is to open the shelter and should identify the backup personnel necessary to respond during every possible event.
Signage. Signage is critical for users to be able to readily find and enter the shelter. In addition to directing users to the shelter, signs can also identify the area the shelter is intended to serve. Confusion about who may use the shelter could result in overcrowding in the shelter, or, worse, people being turned away from the shelter. Signs can also inform the residents of the neighborhood served by the shelter about the occupancy limitations during any given event. Examples of tornado shelter signage are presented in FEMA 361, Chapter 9 and the North Carolina shelter case study in Appendix C.
Warning Signals. It is extremely important that shelter users know the warning signal that means they should report to the shelter. The owners/operators of shelters should conduct public information efforts (e.g., mass mailings, meetings, flyer distribution) to ensure that the residents of the neighborhood served by the shelter know the meaning of any warning signals to be used.
Parking. Parking at residential shelters can be a problem. Neighborhood residents, who are expected to walk, may instead drive to the shelter from their homes. Residents returning home from work may drive directly to the shelter. Parking problems can adversely affect access to the shelter, again preventing occupants from getting to the shelter before a tornado strikes. The Shelter Operations Plan should clearly discuss parking limitations.
Pets. Many people do not want to leave their pets during a disaster. However, tornado shelters are typically not prepared to accommodate pets. The policy regarding pets in a community shelter should be clearly stated in the Shelter Operations Plan and posted to avoid misunderstandings and hostility when residents arrive at the shelter.
Maximum Recommended Occupancy. In determining the maximum recommended number of people who will use the shelter, the design professional should assume that the shelter will be used at the time of day when the maximum number of residents is present. A community may also wish to consider increasing the maximum recommended occupancy to accommodate additional occupants such as visitors to the community who may be looking for shelter during a wind event. The maximum recommended occupancy should be posted within the shelter area.

Tornado Shelter Square Footage Recommendations

Section 8.2 recommends a minimum of 5 ft2 per person for tornado shelters. However, other circumstances and human factors may require the shelter to accommodate persons who require more than 5 ft2. Square footage recommendations for persons with special needs are presented below; these recommendations are the same as those provided in the FEMA 1999 National



Performance Criteria for Tornado Shelters:
• 5 ft2 per person adults standing
• 6 ft2 per person adults seated
• 5 ft2 per person children (under the age of 10)
• 10 ft2 per person wheelchair users
• 30 ft2 per person bedridden persons
Stand-Alone Shelters

The best solution to providing protection for large numbers of people is to build a new, separate (i.e., stand-alone) building specifically designed and constructed to serve as a tornado shelter.


Potential advantages of a stand-alone shelter include the following:

• The shelter may be sited away from potential debris hazards.

• The shelter will be structurally separate from any building and therefore not vulnerable to being weakened if part of an adjacent structure collapses.

• The shelter does not need to be integrated into an existing building design.


Single-Use Shelters

Single-use shelters are, as the name implies, used only in the event of a natural hazard event. One advantage of single-use shelters is a potentially simplified design that may be readily accepted by a local building official or fire marshal. Single-use shelters typically have simplified electrical and mechanical systems because they are not required to provide normal daily accommodations for people. Single-use shelters are always ready for occupants and will not be cluttered with furnishings and storage items, which is a concern with multi-use shelters. Simplified, single-use shelters may have a lower total cost of construction than multi-use shelters.


Multi-Use Shelters

The ability to use a shelter for more than one purpose often makes a multi-use stand-alone or internal shelter appealing to a shelter owner or operator. Multiuse shelters also allow immediate return on investment for owners/operators; the shelter space is used for daily business when the shelter is not being used during a tornado.


Distance/Travel Time and Accessibility
For tornadoes, the time span is often short between the NWS warning and the onset of the tornado. This manual recommends that a tornado shelter be designed and located in such a way that the following access criteria are met: all potential users of the shelter should reside within 1/2 mile and be able to reach it within 5 minutes.
Travel time may be especially important when shelter users have disabilities that impair their mobility. Those with special needs may require assistance from others to reach the shelter; wheelchair users may require a particular route that accommodates the wheelchair. The designer must consider these factors in order to provide the shortest possible access time and most accessible route for all potential shelter occupants.
Americans with Disabilities Act (ADA)

The needs of persons with disabilities requiring shelter space should be considered. The appropriate access for persons with disabilities must be provided in accordance with all Federal, state, and local ADA requirements and ordinances. If the minimum requirements dictate only one ADA compliant access point for the shelter, the design professional should consider providing a second ADA-compliant access point for use in the event that the primary access point is blocked or inoperable. Additional guidance for compliance with the ADA can be found in many privately produced publications.



Special Needs

The use of the shelter also needs to be considered in the design. The design professional should be aware of the need of specific users for whom a shelter is being constructed. Occupancy classifications, life safety code, and ADA requirements may dictate the design of such elements as door opening sizes and number of doors, but use of the shelter by hospitals, nursing homes, assisted living facilities, and other special needs groups may affect access requirements to the shelter. For example, strict requirements are outlined in the IBC and the model codes regarding the provision of uninterruptable power supplies for life support equipment (e.g., oxygen) for patients in hospitals and other healthcare facilities.


Emergency Supplies

Shelter space should contain, at a minimum, the following safety equipment:


• Flashlights with continuously charging batteries (one flashlight per 10 shelter occupants)
• Fire extinguishers (number required based on occupancy type) appropriate for use in a closed environment with human occupancy, surface mounted on the shelter wall
• First-aid kits rated for the shelter occupancy
• NOAA weather radio with continuously charging batteries
• Radio with continuously charging batteries for receiving commercial radio broadcasts
• Supply of extra batteries to operate radios and flashlights
• Audible sounding device that continuously charges or operates without a power source (e.g., canned air horn) to signal rescue workers if shelter egress is blocked
Community Shelter Operations Plan
Disaster preparedness is crucial to quick and effective responses to emergency situations. Potential owners and managers of tornado shelters should be ready and able to open a shelter for immediate use in response to an extreme-wind event. The best way to accomplish this is to create a Shelter Operations Plan tailored to the needs of the intended users of the shelter.
Each shelter designed according to the guidance in this manual should have a Shelter Operations Plan. The plan should describe the difference between tornado watches and warnings and clearly define the actions to be taken for each type of forecast. A Community Shelter Management Team composed of members committed to performing various duties should be designated.
FEMA 361, Chapter 9 addresses baselines that present the minimum information that should be contained within the Shelter Operations Plan.
*** A draft operations plan must be submitted with the project application***
Application Requirements Addressing the Target Population
In order to properly evaluate the community shelter proposal, the following must be addressed in the application;

  • How was the target population calculated?

  • Where is the target population coming from?

  • Will they walk or drive?

  • Is there sufficient parking space?

  • Will going to the shelter cause traffic congestion?

  • Can the target population reach the shelter in 5 minutes of a warning?

  • Can the doors be secured within 10 minutes of a warning?

  • Will going to the shelter create more risk of injury or loss of life than sheltering in place?

Allowable Costs
Allowable costs for shelter projects are those project components such as design and building costs directly related to and necessary for the primary purpose of providing immediate life safety protection to the target population during extreme wind events.
FEMA will only consider as eligible costs those that are consistent with the approved performance criteria (FEMA 361, NSSA, ICC-500) which generally included;


  • Design activity,

  • Site preparation and building foundation and construction,

  • Structural systems capable of resisting the design wind loads (250 mph) including roof decking and support structures,

  • Protective envelope components such as;

    • Walls, ceiling/roof systems and doors and,

    • Other retrofit hardening activities that meet the performance criteria.

  • Functional components to meet minimum code requirements such as;

    • Permanent electrical lighting, ventilation, toilets and hand washing facilities and,

    • Signage, emergency communications, back-up generation for the safe area.

  • Operations and Maintenance Plan development.

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