James E. Waller, P. E. July 5, 2012

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1 Factors Influencing Adoption or Rejection of IS-STM40-11/12 and IS- STM41-11/12, Section Fire Resistance, or Alternate Proposals Pertaining to ICC-500, 2008, Section 601.1, Fire Separation Executive summary James E. Waller, P. E. July 5, 2012 IS-STM40-11/12 and IS-STM41-11/12, Section Fire Resistance, proposed by Jason Pirtle, P. E. and James E. Waller, P. E. were rejected by the Administrative/Non- Structural Task Group of the IS-STM Committee in a teleconference meeting on June 22, Proposal IS-STM41-11/12 is attached as Appendix A to this paper. The reason for the above proposals was that requiring compliance with ICC Section effectively precludes compliance with Sections and for storm shelters enclosed in a host building. In lieu of requiring 2-hour separation for storm shelters in host buildings, the proponents recommended that they have a fire resistance as required by the applicable building code. In support of their positions, the proposers pointed out the mutually exclusive requirements for providing fire resistance and uninterrupted ventilation for shelter occupants after the windstorm event without resulting death or injury of occupants due to smoke inhalation. These conflicting requirements are cited in IS-STM41-11/12 which is included in Appendix A. Additional technical information on this issue is contained in an attached letter from McKenzie C. Roberts, P. E. 2 Reference is made herein to conflicting requirements in the current edition of ICC The purposes of this paper are to introduce supplemental information and documentation which bear on the issue of Section Fire Resistance and to raise the following pertinent questions which the Committee should consider during deliberation on this issue: Are the provisions of Section Fire Resistance requiring protection of storm shelter occupants from fire occurring simultaneously with, or as the direct result of, a hurricane or tornado event consistent with the scope of ICC-500 as stated in the FOREWORD of the Standard? Do other requirements of ICC-500 conflict with the requirement of Section Fire Resistance? Was the multiple-hazard guidance of FEMA P regarding fire resistance of storm shelters considered when writing Section Fire Resistance? Have the relative costs and feasibility of fire-resistant ventilation systems versus standard ventilation systems for internal storm shelters been evaluated considering the requirement for functionality of ventilation systems after a tornado event and during a fire? Will the provisions of ICC-500, Section Fire Resistance and the increased costs and feasibility considerations facilitate or discourage construction of competent storm shelters in host buildings? 1

2 Is the requirement for fire-resistance of storm shelters in host-buildings based on the requirement for protection against the spread of fire or for the protection of storm shelter occupants from fire and smoke inhalation during occupancy of the shelter? Will the requirement for fire protection in community storm shelters create a false impression with the public that storm shelters are areas of refugee from fire within a building? Should the fire resistance requirements for smaller, dispersed tornado shelters in host buildings be treated the same as mega-storm safe rooms sheltering several hundred occupants within a host building? Does the 2012 IBC 4 provide design professionals sufficient guidance for design of fire resistance for varying occupancy types and numbers, construction types, and types of storm shelter entry? Was available statistical evidence regarding the probability of hurricane or tornado-induced fires evaluated in determining the need for fire resistance of storm shelters located within host buildings? Has the risk of a windstorm-initiated fire been weighed against the additional construction cost for fire-resistance and ventilation of storm shelters located in host buildings? Have the needs or requirements of facilities owners/managers for locating storm shelters within host buildings been considered? Has the need for fire resistance of storm shelters in fire-resistant, non-combustible (Type IIB) construction host buildings or in large volume building interiors been considered? Has a quantitative evaluation been performed to determine the probable number of storm shelters which, due to owner/manager preferences, ordinances, or granting authority mandates, must be located within host buildings? Scope and development of ICC The ICC/NSSA Standard FORWARD, Introduction states: The scope of the standard is to provide minimum design and construction requirements for storm shelters that provide a safe refuge from storms that produce high winds, hurricanes, and tornadoes. [Emphasis added.] 5 The ICC/NSSA Standard FORWARD, Development states: The requirements of ICC/NSSA 500 are based on the intent to establish provisions consistent with the scope of the ICC family of codes and standards that are written to adequately protect public health, safety and welfare; provisions that do not necessarily increase construction costs; provisions that do not restrict the use of new materials, products or methods of construction; and provisions that do not give preferential treatment to particular types or 2

3 classes of materials, products or methods of construction. [Emphasis added.] 5 Probability of tornado-caused fire versus cost of storm shelter construction The following proposed commentary for ICC-500, Section influenced the decisions of the IS-STM committee in the standard language embodied in Section Fire Separation. The likelihood of a fire occurring simultaneous with a major natural disaster such as earthquakes or hurricanes is very low, and, historically, these events are always considered separately in a design. However, for the concept of a safe room during the actual event, the scenario is considerably different than that envisioned in the model codes. In this scenario, the occupants of a building have been instructed to quickly seek refuge by crowding into a single room or space in that building, and waiting through a storm. This leaves concern for the possibility that some activity, machinery, or process was left behind which could be a source of ignition for building contents. Therefore, this committee chose to account for that possibility and require some fire separation. It should be noted that the Committee accounted for the possibility rather than the probability of fire after concluding that the probability of fire was very low. In a section entitled Wind Design Context for Tornadoes 6, a combined NIST/NOAA research team conducting the May 22, 2011 Joplin MO Tornado Study, led by IS-STM Committee member, Marc Levitan, presented a summary conclusion regarding national codes, standards, and practices related to life safety in tornadoes. Trade-offs between risks and costs are made during the model building codes and standards development process and during adaptation and enforcement at the state and local level. This task group, consisting of four nationally and internationally renowned tornado researchers, was tasked with producing a technical basis for cost-effective changes in national codes, standards, and practices for buildings and storm shelters to mitigate damage and reduce deaths and injuries resulting from tornadoes. Evaluation of comparative costs for providing fire resistance of storm shelters in host buildings while retaining functional ventilating systems following a design windstorm depends on many factors. Whether the storm shelter is a retrofit feature or part of a newly designed building is probably the most significant factor. Relative costs notwithstanding, the feasibility of providing fire resistance in conjunction with natural ventilation is an issue due to the requirements of ICC-500, Section and Section

4 Location of ventilation openings which require specific minimum percentages of vent openings in the upper and lower halves of a storm shelter. Natural ventilation is unquestionably much more economical for storm shelters than mechanical ventilation which must meet the stringent requirements of ICC-500, Section Mechanical ventilation (tornado shelters) or Section Mechanical ventilation (hurricane shelters), both of which invoke the stringent and costly provisions of Section Protection of critical support systems. But, even with natural ventilation, the issue of conveyance of intake and exhaust air to and from the exterior of the host building and beyond becomes a significant cost and feasibility consideration given that the conveyance system must withstand the forces and debris impacts of the design storm. Providing natural ventilation of a storm shelter is relatively inexpensive. The costs of providing fireresistant passive ventilation are unarguably large and, in cases where a storm shelter is retrofitted into an existing building, the costs may be astronomical. Causes of fires in non-residential buildings Although cooking results in the largest number of fires in the United States, the leading cause of death from fires is unintentionally set fires. From 2003 to 2007 the leading causes of fires were as follows. 7 Intentionally set 24% Unintentionally set 19% Equipment 14% Smoking 11% Non-residential fires constitute less than one-third of fires in the nation and result in less than 4 percent of deaths due to fire. 7 Fires caused by tornadoes and other windstorms A source of comprehensive statistics for storm-induced fires is not currently available. The only bases for judgment as to the frequency of tornado-caused fires are the experience of tornado damage assessment teams, published research reports, research personnel interviews, news media reports, and postings of information to the internet. This writer has investigated post-tornado damage for numerous tornadoes throughout the United States. In no case did he find evidence of a fire resulting from any tornado. Larry Tanner, P. E., Wind Science and Engineering Research Center, Texas Tech University, has been a FEMA investigator for Hurricane Katrina and a researcher and author of numerous published papers on tornado damage assessments in the United States ( In response to an inquiry by this writer as to the frequency of tornado-caused fires, Tanner responded as follows. 4

5 I have (found) only one case of fire that was caused by a tornado, which was the OKC 1999 storm. The fire was caused by a broken gas line and a first responder smoking. The home had been evacuated. Fires can certainly be an issue with causes ranging from transformer explosions, to gas leaks, etc. However, the utility companies are usually quick to de-energize electrical and gas utilities in the affected areas. I cannot image why there should be such consternation over fires and shelters. 8 Tanner s assessment is supported by a report published in the American Journal of Epidemiology regarding the massive 1999 Oklahoma City tornado. 9 The report reads in part: Considering the number and power of the tornadoes, the magnitude of destruction, and the population density of affected areas, surprisingly few deaths were attributed to the Oklahoma tornadoes of May 3, Continuous tracking and media coverage of the F5 tornado provided detailed projections of its path, often 30 minutes or more before it arrived in specific communities (9). Most of the fatalities and severe injuries occurred directly from the force of the F5 tornado. The approximately 211 Alabama tornadoes of 2011, which resulted in some 337 deaths, were widely covered in the news media and internet reports. There is no indication that tornado-induced fires or deaths or injuries from fires following tornado strikes had occurred. The Joplin Globe cited an incident wherein a house fire resulted several days after the May 11, 2011 tornado in which candles for lighting accidently set a fire. There were no other fires reported which can be directly attributed to this destructive, widespread EF-5 tornado. 10 Relative risk of tornado-caused fire for stand-alone safe rooms and safe rooms in host buildings The various sources of fires (downed power lines, broken gas lines, accumulations of storm debris) can be expected to be similar for internally and externally situated safe rooms. Research of recent EF-3 through EF-5 tornado strikes on most non-residential buildings will most likely indicate these sources of potential fires to be statistically equal for locations within or outside of a building. The current ICC-500 standard only requires fire-resistance ratings for community storm shelters (safe rooms) located within host buildings. Since the statistical fire risk significance of shelter site location is relatively small compared to the type of shelter construction and the combustibility of the storm shelter and host building structure components, the current standard is unnecessarily biased against in-host building safe rooms. In an to this writer, Jason Pirtle, P. E. points out that ICC-500 makes no exceptions to providing fire resistance for building occupancies where no gas, flammable materials or activities are present. 16 He further 5

6 points out that the standard also does not account for the presence of gas meters adjacent to stand-alone storm shelters which might be ignited and fueled by accumulated storm debris. ICC-500 currently does not require fire resistance ratings for in-residence storm shelters. Although justification for this is cited above, the majority of residences, and many in-residence shelters meeting FEMA P are combustible construction. The probability of fire being initiated by storm damage around a community shelter located within a non-residential host building is statistically the same as can be expected for an in-residence shelter or for a storm shelter which is not contained within a host building. Fire risks for occupants of storm shelters within prefabricated metal host buildings A large percentage of non-residential buildings in the United States are prefabricated metal buildings. The total market share for non-residential metal buildings during 2011 was 52.5%. 12. The breakdown for non-residential metal buildings is shown below. 12 Commercial 31% Community 24% Manufacturing 21% Miscellaneous 14% Agricultural 8% It is noteworthy that at least 76% of these non-residential prefabricated metal buildings are occupied buildings. Prefabricated metal buildings typically qualify as Type IIB (unprotected, noncombustible) construction. 13 The 2012 IBC, Table 601, Fire Resistance Rating Requirements for Building Elements (Hours), requires no fire rating for Type IIB construction. Metal buildings are designed in accordance with codes and standards for basic design wind speeds specified in ASCE Wind speeds occurring during severe windstorms always exceed basic design wind velocities specified in ASCE 7 14 by large margins. The frangible nature of light gauge metal components and cladding of prefabricated metal buildings render building occupants susceptible to serious injury from wind-driven building components and cladding during severe windstorms where wind speeds significantly exceed the basic design wind speed for the building. Thus, a large percentage of workers in the United States, who occupy prefabricated metal buildings of non-combustible construction, are at risk of injury or death from severe windstorms unless storm protection is provided by safe rooms. ICC-500 currently discourages construction of storm safe rooms within host buildings by requiring a 2-hour fire separation between the safe room occupancy and that of the host building. This no exception requirement does not consider whether fire resistance ratings are required for the particular host building construction type or occupancy, or take into account the type of construction or occupancy of the storm shelter. Further, the requirement does not account for the existence of large areas and volumes of space above 6

7 an interior community storm shelter whose roof and walls may be separated from the roof and exterior walls of the prefabricated metal host building. Such conditions, which cannot be presumed or excluded in an inflexible one size fits all requirement of the standard would appear to be more appropriately determined by the authority having jurisdiction. A portable community storm shelter, temporarily housed in a steel maintenance building in an oil field for protection of workers, would currently violate the requirements of the ICC-500 standard. Reasons for locating community safe rooms in host buildings Reduced travel time to shelters (quick access for short-notice tornadoes). Occupants are not directly exposed to extreme weather conditions (large hail, lightning, wind-driven debris) while entering or leaving the safe room. Building setback requirements do not permit sufficient space for safe rooms to be constructed outside of a host building. Granting authorities, insurers, zoning ordinances, or company policies require the safe room to be within the host building. Host building weather protection in the interior of the building during normal weather conditions reduces safe room construction costs. Host building slabs on grade may qualify as foundations for above ground safe rooms. Business desires to maintain proprietary information in a safe room within the host building. Business desires that the safe room protect IT or other vital business functions from storm damage within the host building. Business desires to limit occupancy of a safe room to its personnel and customers. Business desires to prevent public knowledge of the existence of a safe room on its premises. Conditions of safe room occupants or attached life support equipment require that safe rooms be internal to the facility host building. Legal requirements requiring safe room occupants to remain within a facility host building (airline passengers, prisoners, mental patients, small children, etc.). This writer has observed innumerable examples of spaces within buildings which are mislabeled as storm shelters, some having the tornado funnel cloud symbol, others having Tornado Shelter or Storm Shelter signs on doors. Most of the spaces so labeled consisted of restrooms, break rooms, or storage rooms which were constructed of unreinforced 8 inch concrete masonry walls, open web steel joist roofs with metal deck roofs, suspended ceilings and fixtures, and standard passage doors, some being hollow core wood doors. The existence of such unqualified and deceptively labeled storm shelters in buildings is an indication that owners/managers desire to provide some place to direct personnel for safety during a severe windstorm, however poorly that place might perform as a shelter during a severe windstorm. It may be instructive that this writer has never found a deceptively labeled, unqualified storm shelter on the outside of a building. 7

8 Fire protection requirements of FEMA P-361 FEMA P does not provide specific fire resistance requirements for storm shelters and safe rooms. Sections and 4.5 recommend that the multi-hazard approach be used in assessing risks to functionality of storm shelters. Non-storm related risks included are floods, earthquakes, landslides, wildfires, hazardous materials (gasoline, chlorine, or other chemicals), lead paint, asbestos, power lines, gas leaks, explosions, and fire (with resulting smoke and toxic fumes). Section 4.6, Fire Protection and Life Safety, states The safe room should comply with the fire protection and life-safety requirements of the model building code, or the local code governing construction in the jurisdiction where the safe rooms is constructed. No fire resistance ratings are specified. Fire extinguishers are recommended where fire-sprinkler systems are not used. This provision is consistent with ICC-500, Section 602 Fire Protection.. Section 5.5, Community Safe Rooms at Public Facilities, cautions entities having emergency warning/alarm systems to ensure that all persons know when to seek refuge in the safe room and when to evacuate the building during a fire or other hazard. Appendix B, Safe Room Assessment and Design Tools contains a check list which queries Does a combustible gas line run through the refuge area. The issue of penetration of a shelter envelope by hazardous gas or liquid lines is addressed in the second paragraph of ICC-500, Section 310, Penetration of Storm Shelter Envelope by Systems and Utilities. Conflicting requirements for fire resistance and ventilation of storm shelters in host buildings Reference is made to an attached letter from McKenzie C. Roberts, P. E., a practicing mechanical engineer, wherein the requirement for fire resistance and concomitant ventilation of storm shelters in host buildings is critiqued. 3 Roberts letter cites the threat of smoke inhalation during a fire and the virtually mutual exclusivity of the fireseparation requirement and ventilation requirement for a storm shelter located within a host building. Roberts also describes the potentially fatal consequences for building occupants, erroneously believing that a storm shelter is an area of refuge from fire, and entering a storm shelter for protection during a fire rather than evacuating the building. Evacuation of a storm shelter during a fire is essential for life safety of occupants who are within a burning building or adjacent to, but separate from, that building because deaths due to smoke inhalation injuries exceed deaths by due to fire. 2 8

9 Other conflicting provisions of ICC-500 with Section Fire Resistance ICC-500, Section Alcove or baffled entry systems, Figure , and Figure provide for baffled entries into storm shelters where doors are not required for preventing storm debris from entering the protected occupant areas. Shelter construction employing this type of entry within a host building would be in conflict with the fire separation requirement of Section unless the corridor or other occupied area with which the baffled entry was connected was also fire rated. There may be valid reasons why this should be, but there are also cases where the requirement is unnecessary and detracts from the unique advantages of baffled entries to storm shelters. However, a baffled entry without a door, as described in the aforementioned section and figures of Section 804, does not qualify as a fire rated opening unless the baffled entry opens to the exterior of a building or a stand-alone storm shelter. Does this properly define the intent of these standard provisions? The Committee is advised to consider questions regarding fire resistance of adjoining, covering, or enclosing structures and occupancies such as the following. Restrooms in rest stops and welcome stations along interstate highways typically have baffled entries. These facilities, which also have mechanical rooms for HVAC and plumbing, are typically under a single roof. Can these restrooms qualify as community storm shelters if the entries to the restrooms open to the exterior of the building or into a fire rated corridor? Does a fire rated mechanical room for the facility being under the same roof as the restrooms require that these restroom storm shelters also be fire rated? If a public restroom serves as a public storm shelter within a fire rated airport concourse should the restroom/storm shelter also require fire resistance? How is ventilation of such restrooms to be handled so that there is no interruption of ventilation after a tornado? If a public restroom or locker room within a sports stadium is constructed as a storm shelter is the shelter considered to be within a host building if the only enclosing structures are bleachers and vomitories having openings to the exterior of the stadium structure? Conclusions The philosophy embodied in the NIST/NOAA summary conclusion should influence the decision of the IS-STM Committee regarding the current, disparate fire resistance requirement of Section Fire Separation for storm shelters outside of and internal to host buildings. The scope of ICC-500 is to provide protection from tornadoes and hurricanes. This paper has discussed the low risk of tornado-initiated fires and the statistically equal risk to occupants from fire whether occupying shelters which are inside and outside of host buildings. The case has not been made that fire resistance for storm shelters within or attached to host buildings is greater than for storm shelters which are in the open. The proposed amendment to Section Fire Separation in Recommendation, below should be adopted by the Committee to eliminate the disparity 9

10 in construction costs between stand-alone and in-host building storm shelters. The absence of proof of increased risk of fire in buildings after tornadoes, weighed against the no-exception provisions of Section 601.1, must be judiciously considered by the Committee. Whether ICC-500 facilitates or discourages construction of storm shelters in host buildings must be seriously considered. The percentage of the population of the United States which might be denied storm shelter protection as the result of the prohibitive costs or mutually exclusive requirements for storm shelters within host buildings due to the mandatory 2 hour fire resistance rating is a factor which the Committee must not fail to consider. Recommendation Revise ICC-500, Section Fire Separation as follows Fire separation. Fire barriers and horizontal assemblies separating spaces or areas designated as storm shelters from other building areas shall have a minimum fire resistance rating of 2 hours and shall be constructed in accordance with the applicable building code. in accordance with the applicable building code. Exception: Fire separation assemblies are not required for residential shelters. 10

11 References cited 1. ICC/NSSA Standard for the Design and Construction of Storm Shelters, ICC , International Code Council, Inc., Letter from McKenzie C. Roberts, P. E., Engineering Consultants & Design, Inc., June 29, Design and Construction Guidance for Community Safe Rooms, FEMA Publication P-361, Second Edition, August International Building Code, International Code Council, Inc., Standard with Commentary, ICC _ (Draft, ICC/NSSA Standard on the Design and Construction of Storm Shelters), February Levitan, M., Draft Study Plan and Research Overview (Briefing for NCST Advisory Committee), NWIRP Research and Development Program, November 7, Fire in the United States , FEMA Publication FA-325, U. S. Fire Administration/National Fire Data Center, Fifteenth Edition, October from Larry Tanner, Wind Science and Engineering Research Center, Texas Tech University, dated June 25, Daley, Brown, Archer, Kruger, Jordan, Batts, & Mallonee, Risk of Tornadorelated Death and Injury in Oklahoma, May 3, 1999, American Journal of Epidemiology, Vol. 161, No. 12, Candle blamed for house fire; no injuries cited, The Joplin Globe, May 30, 2011, Taking Shelter From the Storm: Building a Safe Room For Your Home or Small Business, FEMA Publication P-320, Third Edition, August MBMA Industry Trends, 2011 MBMA Business Review, Metal Building Manufacturers Association, copyright 2012, Fire Resistance Design Guide for Metal Building Systems, Metal Building Manufacturers Association, Minimum Design Loads for Buildings and Other Structures, ASCE/SEI 7-10, Tornado Protection Selecting Refuge Areas in Buildings, FEMA P-431, Second Edition, October from Jason Pirtle, P. E., TLM Associates, Inc., Jackson, TN, July 5,

12 APPENDIX A IS-STM41-11/12 Section Proponent: James E. Waller, PE, representing NSSA Standards Committee Revise as follows: Fire separation. Fire barriers and horizontal assemblies separating spaces or areas designated as storm shelters from other building areas shall have a minimum fire resistance rating of 2 hours and shall be constructed in accordance with the applicable building code. as required by the applicable building code. Shelter construction, including ducts and vent openings for mechanical or natural ventilation for the shelter shall be non-combustible construction. Exception: Fire separation assemblies are not required for residential shelters. Reason: The requirement for a 2 hour fire separation of ICC-500, section Fire Separation is mutually exclusive with the requirements of ICC-500, section Ventilation and section Ventilation for any storm shelter enclosed in a Host Building as permitted by ICC-500, Section 303 SHELTERS ENCLOSED OR PARTIALLY ENCLOSED IN A HOST BUILDING. Compliance with Section 601 precludes compliance with Sections and for storm shelters enclosed in a Host Building for the following reasons. Through wall and through roof venting of storm shelters is required by sections and Required ventilation must have intake/exhaust openings which are external to the Occupied Shelter Areas. Intake/exhaust openings for a storm shelter enclosed in a Host Building typically open to the interior of the Host Building. Alternately, intake/exhaust openings for a storm shelter enclosed in a Host Building can be exterior to the Host Building. Section Protection of Components requires that such ducts be protected from design event conditions. Fire dampers on intake/exhaust openings would not comply with the requirements of ICC-500, sections and ICC-500, section Location of ventilation openings and section Location of ventilation openings specify proportions of natural ventilation which much be located in the lower portion of the shelter and in the upper portion of the shelter. Protection of numerous dispersed ventilation intake/exhaust openings is impracticable and not economically feasible. Ventilation exhaust and intake openings on the outside of storm shelters are required by ICC-500, section Exhaust or intake opening protection and Exhaust or intake opening protection to meet the design and impact testing requirements of ICC-500, section Wall and roof openings which requires compliance with section Opening protective devices. ICC-500, section Intake openings and section Intake openings specify the minimum separation of intake openings from any hazardous or noxious contaminant. Smoke generated by a fire within a Host Building must be construed as a hazardous or noxious contaminant which is omnipresent within the Host Building. 12

13 Alcove/baffled entry systems for storm shelters, as shown in ICC-500, Figure and Figure , would not be permitted by section within a Host Building. Alcove/baffled entry systems within Host Buildings are particularly appropriate for interior facilities such as restrooms and dedicated storm shelters where unrestricted public access is required by the Authority Having Jurisdiction or the owner for safety or liability reasons. The provisions of ICC-500, section Fire Separation, preclude practicable and economical construction of storm shelters enclosed in a Host Building for the reasons presented herein. Exclusion of storm shelters in Host Buildings will adversely affect the storm shelter industry and discourage entities from providing storm shelters meeting the requirements of ICC-500 within the premises of manufacturing facilities, businesses, hospitals, schools, government facilities, and the like. The requirement to protect storm shelter occupants from fire simultaneously with a windstorm event is inconsistent with the scope of ICC-500 as stated in FOREWORD of the standard (see End Note 1) IBC, section 603 Combustible Material in Type II and III Construction, Table 601, does not require fire resistance ratings for Type IIB or IIIB construction except for exterior walls of Type IIIB construction. Table 601 also permits approved sprinkler systems complying with Section to be substituted for 1-hour fire resistance rated construction for Type IIA and IIIA construction. ICC-500, section 601.1, provides no exceptions for fire sprinkler systems in buildings for storm shelters or for waivers of construction from the building official based on the applicable building code or unique Host Building conditions or occupancy IBC, section Scope, is limited to safeguarding against the spread of fire and smoke within a building and the spread of fire to or from buildings. The scope does not include the requirement for providing ventilation to occupants within a building during a fire. The primary requirements embodied in life safety codes and egress provisions of building codes involve providing safe means of egress from a building in the event of a fire or suppression of fire where egress is hampered. For example, 2009 IBC, section requires fire sprinkler systems for Group A-3 occupancies where a. the fire area exceeds 12,000 square feet b. the fire area has an occupant load of 300 or more c. the fire area is located on a floor other than the level of exit discharge ICC-500, section Number of doors, states that The number of means of egress doors from a space shall be determined based upon the occupant load for the normal occupancy of the space in accordance with the applicable building code. For facilities used solely for shelters, the number of doors shall be determined in accordance with the applicable building code based upon the occupant load as calculated in section This is consistent with the 2009 IBC (End Notes 2 and 3 and FEMA 361 (End Note 4). [Emphasis added.] The second paragraph of section states Where the applicable building code requires only one means of egress door, an emergency escape opening shall be provided as calculated in accordance with section Section 501.4, Emergency escape opening, states The emergency escape opening shall be an additional door or an opening that is a minimum of 5.7 square feet (0.530 m2) in area. This requirement is clearly intended to assure rapid egress from a storm shelter after a storm, unimpeded by storm debris blocking a single egress door. In conjunction with the requirement to base the minimum number of doors on occupancy as a storm shelter in accordance with the applicable building code, the emphasis is clearly on insuring that occupants can quickly exit the storm shelter after the storm event. Therefore, providing protection of shelter occupants from a fire outside the shelter should not be a requirement for storm shelter construction. 13

14 End Notes Foreword of ICC-500, 2008, Introduction The scope of the standard is to provide minimum design and construction requirements for storm shelters that provide a safe refuge from storms that produce high winds, hurricanes and tornadoes IBC, Section 104 Duties and Powers of Building Official Section The building official shall have the authority to render interpretations of this code and adopt policies and procedures in order to clarify the application of its provisions. Such interpretations, policies and procedures shall be in compliance with the intent and purpose of this code. Such policies and procedures shall not have the effect of waiving requirements specifically provided for in this code. Section The building official shall issue all necessary notices or orders to ensure compliance with this code IBC, Section 102 Applicability Section Referenced codes and standards. Where differences occur between provisions of this code and referenced codes and standards, the provisions of this code shall apply. FEMA 361, 2008 Edition, Section 4.6 Fire Protection and Life Safety The safe room should comply with the fire protection and life-safety requirements of the model building code, the state code, or the local code governing construction in the jurisdiction where the safe room is constructed. 14

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