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BALANCED FIRE PROTECTION: ARE SMOKE/HEAT VENTS NECESSARY FOR OCCUPANT AND FIREFIGHTER SAFETY IN ONE-STORY INDUSTRIAL AND STORAGE BUILDINGS PROTECTED BY STANDARD SPRAY SPRINKLERS?. Presented to: ICC Code Technology Committee Cincinnati, Ohio June 20, 2007.
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BALANCED FIRE PROTECTION:ARE SMOKE/HEAT VENTS NECESSARY FOR OCCUPANT AND FIREFIGHTER SAFETY IN ONE-STORY INDUSTRIAL AND STORAGE BUILDINGS PROTECTED BY STANDARD SPRAY SPRINKLERS? Presented to: ICC Code Technology Committee Cincinnati, Ohio June 20, 2007
CODE CHANGE F124-06/07FIRE CODE COMMITTEE DISAPPROVAL REASON “There was no definitive information presented that smoke and heat vents do not contribute to fire control.” “In cases where the sprinkler system does not suppress the fire but, rather, controls it, smoke continues to be generated.” “The discussions have focused on everything but the safety of the occupants, including firefighters.”
CODE CHANGE F124-06/07FIRE CODE COMMITTEE DISAPPROVAL REASON “Smoke and heat vents provide the fire department with an important tool to remove the smoke for occupant safety and enhanced fire attack access, especially in very large area buildings where access from the exterior is limited at best.” “Firefighter safety is also improved by providing a faster, safer method of fire ventilation than cutting one or more holes in the roof.” “The current text presents a balanced approach between firefighter safety and building safety.”
ORIGINAL PURPOSE OF SMOKE/HEAT VENT PROVISIONS What was the original intended purpose for requiring automatic smoke/heat vents and draft curtains in one story industrial and storage buildings (including buildings containing high- piled storage) protected by a sprinkler system as required by the UBC/UFC? Assist with manual interior firefighting (in both sprinkler control and sprinkler failure fire scenarios). Reduce property damage (building and contents).
EXPECTED PERFORMANCE OF SMOKE/HEAT VENTS What was/is the expected performance of automatic smoke/heat vent installations complying with the UBC/UFC and IBC/IFC provisions for smoke/heat vents and draft curtains? Unknown.Neither the UBC/UFC or IBC/IFC contain any performance criteria for smoke/heat vent installations.(UBC/UFC; IBC/IFC) A fire in a bulk retail building in Tempe, Arizona suggests the UBC/UFC roof vent/draft curtain provisions are inadequate where the sprinkler system is operational, but inadequate for the hazard. (NFPA Fire Investigation)
INTERACTION OF STANDARD SPRAY SPRINKLERS AND DRAFT CURTAINS Do draft curtains interfere with the operation of standard spray sprinklers? Draft curtains may increase the number of sprinklers which operate. FMRC Research 1994; NFPRF Research 1997/1998 Draft curtains may cause a distortion in the sprinklers which operate. NFPRF Research 1997/1998 Draft curtains may interfere with “pre-wetting” of combustibles. FMRC Research 1994; NFPRF Research 1997/1998
DELETION OF DRAFT CURTAIN PROVISIONS IN THE IBC/IFC Was the expected performance of automatic smoke/heat vent installations adversely affected when the requirement for draft curtains was removed from the UBC/UFC provisions for smoke/heat vents during the drafting of the IBC/IFC? Smoke/heat vents and draft curtains are a team; the rate of venting through open vents is dependent upon the temperature and the depth of smoke layer. NFPA 204 Not providing draft curtains (per the UBC/UFC) will reduce both the temperature and depth of the smoke layer. “There is a movement to use smoke vents without draft curtains There is no R&D basis for this approach” Dr. Craig Beyler, Hughes Associates, Inc.
OPERATION OF VENTS IN SPRINKLERED BUILDINGS How many smoke/heat vents will automatically open in buildings protected by standard spray sprinklers if the sprinkler system operates and controls the fire (as expected by NFPA 13)? “. . . . .current design practices are likely to limit the number of vents operated to one and vents may in fact not operate at all in very successful sprinkler operations.” Dr. Craig Beyler, Hughes Associates, Inc. “Not only is the fear of early operation not founded, current design practice will likely lead to 0-1 vents operating” Dr. Craig Beyler, Hughes Associates, Inc.
PROTECTION OF BUILDING STRUCTUREBY STANDARD SPRAY SPRINKLERS Will standard spray sprinklers protect the building structure from damage without smoke/heat vents (assuming that the sprinkler system is operational and adequate for the hazard being protected)? The listing criteria for standard (spray) sprinklers specifically tests the ability of sprinklers to protect the building structure. UL 199 “Fires that occur in rack storage occupancies are likely to be controlled within the limits outlined in B-1.1, since no significant building damage is expected.” NFPA 13
PERFORMANCE CAPABILITIES OF STANDARD SPRAY SPRINKLERS Will standard spray sprinklers control and extinguish a fire without intervention by firefighters (assuming the sprinkler system is operational and adequate for the hazard being protected)? “Sprinkler protection installed as required in this standard is expected to protect the building occupancy without supplemental fire department activity.” NFPA 13
PERFORMANCE CAPABILITIES OF STANDARD SPRAY SPRINKLERS Will standard spray sprinklers reduce the temperature within the building without intervention by firefighters (assuming the sprinkler system is operational and adequate for the hazard)? “During the testing program, the installed automatic extinguishing system was capable of controlling the fire and reducing all temperatures to ambient within 30 minutes of ignition.” NFPA 13
IMPACT OF SPRINKLER OPERATION ON VENTING Will the operation of standard spray sprinklers adversely impact the venting rate of smoke/heat vents? The operation of standard spray sprinklers rapidly reduces ceiling temperatures. UL 199; NFPRF Research 1997/1998 A reduction in the ceiling temperature caused by the operation of sprinklers will reduce the venting rate through open vents. NFPA 204
ALTERNATIVES TO ROOF VENTS Is it essential for firefighting operations to open smoke/heat vents (provided per the IBC/IFC in buildings protected by standard spray sprinklers) if the sprinkler system operates and controls the fire or can the venting of smoke be accomplished in some other manner (i.e. opening large exterior doors)? “Sprinkler protection installed as required in this standard is expected to protect the building occupancy without supplemental fire department activity.” NFPA 13 “During the testing program, the installed automatic extinguishing system was capable of controlling the fire and reducing all temperatures to ambient within 30 minutes of ignition.” NFPA 13
ROOF VENT OPERATION IN THE EVENT OF SPRINKLER SYSTEM FAILURE TO CONTROL FIRE Will automatic smoke/heat vents provided per the IBC/IFC automatically open in buildings protected by standard spray sprinklers if the sprinkler system operates, but fails to control the fire? Bulk Retail Facility Fire, Tempe, Arizona, March 19, 1998: Sprinkler design based on a maximum of 29 sprinklers operating; 66 sprinklers actually operated. 29 smoke/heat vents provided in building; 3 smoke/heat vents actually operated. Building filled with smoke from floor to ceiling when Phoenix Fire Department arrived. NFPA Fire Investigation Report
MANUAL OPENING OF ROOF VENTS IN THE EVENT OF SPRINKLER SYSTEM FAILURE TO CONTROL FIRE Should firefighters manually open smoke/heat vents which do not open in buildings protected by standard spray sprinklers if the sprinkler system operates, but fails to control the fire? “Steel trusses are also prone to failure under fire conditions and may fail in less time than a wooden truss under the same conditions.” “Lives will continue to be lost unless fire departments make appropriate fundamental changes in firefighting tactics involving trusses.” “NIOSH recommends that fire departments, fire fighters, building owners and managers take steps to minimize the risk of injury and death to fire fighters during fire fighting operations involving structures with truss roof and floor systems.” NIOSH 2005-132
ROOF VENT OPERATION IN THE EVENT OF SPRINKLER SYSTEM FAILURE TO DISCHARGE WATER Will automatic smoke/heat vents provided per the IBC/IFC automatically open in buildings protected by standard spray sprinklers if the sprinkler system fails to operate (i.e. closed water supply valve, broken supply piping or pump failure)? Yes.
FIREFIGHTER SAFETY From a firefighter safety standpoint, should firefighters conduct interior manual firefighting operations in the event the sprinkler system operates, but fails to control the fire? “Steel trusses are also prone to failure under fire conditions and may fail in less time than a wooden truss under the same conditions “Fire fighters should be discouraged from risking their lives solely for property protection activities.” "Use defensive strategies whenever trusses have been exposed to fire or whenever structural integrity cannot be verified. Unless life-saving operations are under way, evacuate fire fighters and use an exterior attack [Brannigan 1999; Dunn 2001].“ NIOSH 2005-132
FIREFIGHTER SAFETY From a firefighter safety standpoint, should firefighters conduct interior manual firefighting operations in the event the sprinkler system fails to operate (i.e. closed water supply valve, broken supply piping or pump failure)? “Steel trusses are also prone to failure under fire conditions and may fail in less time than a wooden truss under the same conditions “Fire fighters should be discouraged from risking their lives solely for property protection activities.” "Use defensive strategies whenever trusses have been exposed to fire or whenever structural integrity cannot be verified. Unless life-saving operations are under way, evacuate fire fighters and use an exterior attack [Brannigan 1999; Dunn 2001].“ NIOSH 2005-132
VOLUNTEER FIRE DEPARTMENT PERSONNEL CAPABILITIES Do most volunteer fire departments have sufficient personnel capabilities to conduct interior manual firefighting operations in large industrial or storage buildings in the event the sprinkler system operates, but fails to control the fire, or when the system fails to operate? “In communities with less than 2,500 population, 21% of fire departments, nearly all of them all-or mostly-volunteer departments, deliver an average of 4 or fewer volunteer firefighters to a mid-day house fire. . . it is likely that most of these departments often fail to deliver the minimum of 4 firefighters recognized by national standards as the necessary minimum for interior fire attack “An estimated 128,000 firefighters, most of them volunteers serving in communities with less than 2,500 population, serve in departments that are involved in structural firefighting but have not certified any firefighters to Firefighter Level I or II.” [US]FA- 303, October 2006
PAID FIRE DEPARTMENT PERSONNEL CAPABILITIES Do most career (paid) fire departments have sufficient personnel capabilities to conduct interior manual firefighting operations in large industrial or storage buildings with the first arriving engine company in the event the sprinkler system operates, but fails to control the fire, or when the system fails to operate? “Sufficient resources required to provide safe manual fire suppression activities are not currently available in most municipalities defended by full time firefighting personnel.” IRC Code Change RB4-06/07 “An estimated 79,000 firefighters serve in fire departments that protect communities of at least 50,000 population and have fewer than 4 career firefighters assigned to first-due engine companies. It is likely that, for many of these departments, the first arriving complement of firefighters often falls short of the minimum of 4 firefighters needed to initiate an interior attack on a structure fire, thereby requiring the first-arriving firefighters to wait until the rest of the first-alarm responders arrive.” [US]FA-303, October 2006
OCCUPANT FIRE SAFETY RISK-INDUSTRIAL AND STORAGE BUILDINGS Are large single-story industrial or storage buildings protected by a sprinkler system (standard spray sprinklers) without roof vents a high risk occupancy from an occupant fire safety standpoint? The NFPA estimates that 50 fire fatalities occurred in U.S. commercial (non-residential) occupancies in 2005. NFPA fire statistics-2005 Commercial occupancies include assembly, business, educational, institutional and mercantile occupancies, as well as industrial and storage buildings.
FIRE INSURANCE CARRIER REQUIREMENTS FOR ROOF VENTS IN SPRINKLERED BUILDINGS Do any fire insurers mandate the installation of smoke/heat vents in buildings protected by a sprinkler system? No. “Reduces Heat and Smoke Damage? Unknown” Dr. Craig Beyler, Hughes Associates, Inc.
FIRE INSURANCE PREMIUM CREDITS FOR ROOF VENTS IN SPRINKLERED BUILDINGS Do any fire insurers offer premium reductions for the installation of smoke/heat vents in industrial or storage buildings protected by a sprinkler system? No. “Reduces Heat and Smoke Damage? Unknown” Dr. Craig Beyler, Hughes Associates, Inc.
RESEARCH ON PROPERTY PROTECTION CAPABILITIES OF ROOF VENTS IN SPRINKLERED BUILDINGS Is there any research that indicates that smoke/heat vents actually reduce property damage in buildings protected by a sprinkler system when the sprinkler system operates or when the sprinkler protection is impaired? “Reduces Heat and Smoke Damage? Unknown” Dr. Craig Beyler, Hughes Associates, Inc.
CODE CHANGE F124-06/07FIRE CODE COMMITTEE DISAPPROVAL REASON “There was no definitive information presented that smoke and heat vents do not contribute to fire control.” NFPRF Research-1997/1998; Bulk Retail Facility Fire, Tempe, Arizona-1998 “In cases where the sprinkler system does not suppress the fire but, rather, controls it, smoke continues to be generated.” NFPRF Research-1997/1998; Bulk Retail Facility Fire, Tempe, Arizona-1998; NFPA 204 “The discussions have focused on everything but the safety of the occupants, including firefighters.” NFPA Fire Statistics-2005; NIOSH 2005-132
CODE CHANGE F124-06/07FIRE CODE COMMITTEE DISAPPROVAL REASON “Smoke and heat vents provide the fire department with an important tool to remove the smoke for occupant safety and enhanced fire attack access, especially in very large area buildings where access from the exterior is limited at best.” NIOSH 2005-132; [US]FA-303 (2006) “Firefighter safety is also improved by providing a faster, safer method of fire ventilation than cutting one or more holes in the roof.” NIOSH 2005-132; [US]FA-303 (2006) “The current text presents a balanced approach between firefighter safety and building safety.” NFPA 13; NIOSH 2005-132
CONCLUSIONS Sprinkler protection is the primary means of protecting large one-story industrial and storage buildings. Draft curtains may have an adverse impact on the ability of standard sprinklers to control a fire. (NFPRF Research-1997/1998; FMRC Research-1994) No building feature which has been shown to potentially interfere with the successful operation of the sprinkler system should be required by the IBC/IFC (i.e. draft curtains).
CONCLUSIONS(CONTINUED) The use of roof vents without draft curtains will adversely affect the venting capability of smoke/heat vents which open. (NFPA 204; Dr. Craig Beyler) The activation of standard sprinklers will adversely affect the venting capability of any smoke/heat vents which open. (NFPA 204) The NFPRF research clearly demonstrated that the maximum number of smoke/heat vents which will automatically open in a building protected by standard (spray) sprinklers (if the sprinkler system is operational and adequate for the hazard protected) is one. (NFPRF Research-1997/1998; Dr. Craig Beyler)
CONCLUSIONS(CONTINUED) If the sprinkler protection is adequate for the hazard protected and is functional, the use of interior manual firefighting in large single industrial and storage story buildings is unnecessary. (NFPA 13) If the sprinkler protection is operational, but inadequate for the hazard protected, or is not functional, interior manual firefighting should not be utilized. (NIOSH 2005-132)
CONCLUSIONS(CONTINUED) The occupant fire safety risk presented by large one-story industrial or storage occupancies protected by a sprinkler system is minimal. (NFPA Fire Statistics-2005) Providing automatic smoke/heat vents in large one-story industrial or storage occupancies protected by a sprinkler system will provide little or no additional occupant fire safety since the occupant fire safety risk is already minimal and since it has been demonstrated that smoke/heat vents may not operate in buildings protected by standard (spray) sprinklers. (NFPA Fire Statistics-2005; NFPRF Research 1997/1998)
CONCLUSIONS(CONTINUED) From the above, it can be concluded that automatic smoke/heat vents provide no significant increase in the level of fire protection and fire safety, including firefighter safety, provided for large single-story buildings containing industrial or storage occupancies protected by standard (spray) sprinklers.
RECOMMENDED CODE CHANGE PROPOSAL ACTION A code change proposal which eliminates the mandatory requirements for smoke/heat vents in single-story industrial and storage buildings protected by standard spray sprinklers should be developed. The code change proposal should include mandatory requirements for some means of ventilating the building. Several design alternatives for providing venting (including manual smoke/heat vents) should be included in this proposal. The purpose of providing some means of ventilating the building should be to assist firefighters in removing smoke from the building after the fire has been controlled and extinguished by the sprinkler system.