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is report offers an overview of the surization, as well as the appropriateness titled “The Use of Elevators in High-Rise ongoing efforts of the the elevator of sprinkler waterflow versus smoke de- Buildings During Fire Emergencies” was rindustry, the NFPA, the National In- tector initiation of elevator recall. It also held at the NFPA Annual Meeting in New stitute for Standards and Technology provided an opportunity to publicize a Orleans in May 1992. (NIST), the American Society of Mechan- number of elevator operation problems Session panelists pointed out that the ical Engineers (ASME), and other in- that were known only to the elevator NFPA Life Safety Code Subcommittee on volved parties to develop solutions to the industry, such as low heat tolerance of Means of Egress had recognized this ba- problems involved in enhancing the secu- microprocessor controls and water sen- sic problem nearly 15 years ago, culmi- rity of elevator systems against various sitivity of door interlock and other eleva- nating in the Section 5-12 proposal that aspects of the fire environment. Their tor equipment in hoistways. was passed by the Safety to Life Commit- goal is the continued use of elevators The 200 attendees, who were elevator tee, but was rejected on the floor at an during fire emergencies. and building officials and fire profession- annual meeting more than a decade ago. als, left the meeting determined that At the time, the prediction was made that Tho symposium some immediate code revisions and fur- if the NFPA membership failed to act In February 1991, the NFPA, the ASME, ther study of local fire service experience favorably on the proposal, the federal and the Council of American Building were steps to be taken as soon as possi- government would force the issue. Officials (CABO) sponsored a symposium ble. A few of these actions are outlined Some European and Asian nations also on elevators and fire in Baltimore, Mary- below. have recognized the problem, and several land. It was organized in anticipation of are ahead of the in the the forthcoming Americans with Disabil- NFPA panel session process of solving it. Currently, we are ities Act and its associated Accessibility in enmeshed in a lack of building code Guidelines (ADAAG). To broaden the fire community’s aware- coordination and a federal law to be The symposium emphasized a number ness of this major exit problem and to enforced by individuals who are long on of well-known questions regarding the report on progress made since the Balti- legal training, but may be unfamiliar with need for elevator lobbies and their pres- more symposium, a special panel session building construction. The Board for the

NFPA Journal May/June 1993 49 - Coordination of Model Codes and the closely related. If a pressurization system control capability for the continued safe Department of Justice (DOJ) are rushing can keep elevator hoistways substan- operation of elevators during a building to establish codes and regulations, but tially clear of heat and smoke, why not fire for double the normal rush-hour there is no one authority to establish a use hoistways as vertical risers to pro- evacuation time and loads carried. It also humanistic approach to implementing vide duplicate and remote electrical places the responsibility for cooling ele- them. power supplies during emergencies? The vator controls with the most concerned failure of nonfire-resistive,single or clus- parties-the elevator manufacturers or Technical problems tered power supplies has resulted in cat- installers. There are still both technical and opera- astrophic losses in several recent high- Few people have had as much opera- tional problems to overcome. The techni- rise building fires. Hoistways can be tional experience in high-rise building cal problems are heat, smoke, water, and better constructed to protect both a fires as Elmer Chapman, retired chief of electric power reliability, most of which building’s occupants and the electrical the Fire Department, who were addressed at the NFPA meeting in power that is needed to descend eleva- was one of the panelists at the New New Orleans. tors for their safe egress. Orleans session. His extensive field expe- Stairwell pressurization has been in For electrical power reliability during a rience led him to develop 13 criteria for use long enough to be a proven method lire, expensive large-capacity, space-con- safe elevator design (see sidebar). of minimizing fire and smoke invasion of suming emergency generators are not the Members of the New Orleans panel that component of means of egress. The answer. The proper solution is duplicate, discussed human factors involved in the same engineering principles apply to ele- remotely run, fire-resistive power lines problem, as well as the hardware require- vator hoistway pressurization, and simi- fed from two separate substations where ments. In fire situations, mobility-im- lar success can be achieved if we recog- available, as in all large cities. paired individuals have no choice but to nize the differences in construction of However, emergency generators are use elevators or to wait in stairwell ref- stair and elevator shafts and their doors. still necessary in hospitals and critical uge areas either until the fire is con- Because most building codes still re- service facilities and for utility outages. trolled or until people can assist them quire venting of elevator hoistways, pro- Smaller units capable of running one down the stairsby using a wheelchair vision must be made to negotiate away elevator car per elevator bank in addition carry, for example. that requirement with the authority hav- to emergency lighting should be pro- There has been a successful 20-year ing jurisdiction, or to supply additional vided. campaign to teach people not to use pressurization air to compensate for that Another heat problem can occur in the elevators in fires, but there is a downside which is lost. The number of stair doors elevator machine room. Most high-speed to not using the elevators for those who open during a fire emergency has been elevators used in high-rise buildings have have a choice of elevators or stairs. the subject of debate and the cause of microprocessor controls that are temper- Longer evacuation time, physical effort design limitations. Fortunately, in the ature-sensitive at degrees varying from required to descend stairs, the potential case of elevators, the maximum design 85°F to 104°F. ASME A17.1, the Elevator for long delays, and fear of stairway condition is one open door (or more, if Code, does not mention air conditioning congestion all are important consider- there is more than one elevator in a in elevator machine rooms because it is ations. The need for phased evacuation shaft). considered a building design function. of public buildings by floors in order to On the other hand, stairwells, unlike Since no model code requires air condi- prevent congestion must be better publi- elevators, can be entered when you ar- tioning in elevator machine rooms, the cized, especially to building occupants. rive at the door. Therefore, it is abso- type and existance of air-conditioning Both occupant training and written emer- lutely necessary to provide lobby smoke equipment there is a local option. gency plans are vital to ensure safe evac- doors at every floor level to create smoke The problem may be compounded by uation. zones separated from the remainder of the fact that some fire department offic- The chairman of the New Orleans ses- the floor areas. Conventional, loose-fit- ers habitually switch off electrical and sion concluded that all the speakers, de- ting elevator doors generally permit air-handling equipment power when they spite the differences in their backgrounds enough air leakage into the lobbies so enter a fire building. Without cooling, the and experience, agreed that when the that a separate, ducted lobby pressuriza- microprocessor controls rapidly over- revisions needed to meet the full intent of tion system is unnecessary. heat due to normal ambient heat released the ADAAG are completed, not much Such a system effectively creates tem- from elevator motors, resistors, and more will be required to provide safe porary areas of refuge and keeps fire, transformers. Loss of cooling is a more evacuation for all building occupants un- heat, and smoke at bay until and unless frequent cause of elevator control failure der fire conditions. the entire floor area is overwhelmed by than is the direct effect of fire. fwe. This is an infrequent occurence, par- The elevator industry is aware of this ASME AW dortr ticularly during the early stages of a fire control sensitivity.A common solution is The ASME A17 Elevator and Escalator when at least one elevator car could to install internal thermostats to shut Committee considered every suggestion reach the fire floor to evacuate occupants down the elevator car instantly when the made by the 16 speakers at the Baltimore waiting in the elevator lobby. In a build- critical temperature is approached; there symposium. Each suggestion was re- ing with a well-maintained sprinkler sys- is a separate control panel for each car. viewed and assigned to one of 24 perma- tem, total floor involvement should never Stopping elevators is no help in evacuat- nent A17 subcommittees or to several occur. However, until the time comes ing people or in fire service operations, A17 ad hoc committees specifically cre- when all high-rise buildings are sprin- and it frequently adds the problem of ated to review and analyze them. klered and the sprinker systems are elevators stalled between floors. Some of the technical work has been tested semiannually, smoke will continue A patent is pending for liquid cooling completed, and a few proposed changes to be a major problem when fire occurs. of microprocessor elevator-control cabi- to the Elevator Code have been submit- Water is a distinct problem requiring a nets, not only to provide more efficient ted to the main A17 committee to be separate solution. It was not discussed at cooling during normal operations, but considered for inclusion in the 1993 edi- the New Orleans session, but will be also to provide a minimum of 1 hour of tion of the Code. covered later in this report. heat absorption capacity if a cooling- After a careful review of fire and ele- Heat and electrical reliability are power failure occurs. This will provide vator industry experience, passage is

May/June 1993 NFPA Journal likely for the following pending sprinkler recommendations that are of particular 13 Criteria for Safe Elevator Design interest to the fire community: Elmer F. Chapman 0 Use sidewall sprinklers in the elevator hoistway pits. Nearly all hoistway fires result from trash accumulation in the e following is a list of 13 pro- protected by smoke detectors. pits. There will be installation stipula- CIposed requirements to ensure el- 7. Elevator systems should be tions to prevent water soaking of the evator safety during fire emergen- made water-resistive. elevator car and the lowest-level door- cies. It is not all-inclusive or in any 8. When a power failure occurs, all closing mechanism and to assure pit order of priority, nor is it a pick-and- elevators should return to their des- drainage. choose list of options. ignated level. 0 Sprinklers are not required at the tops Instead, it is intended as a com- 9. All elevators should be capable of noncombustible hoistways of passen- pendium of safeguards that must be of being operated from a dedicated ger elevators with car enclosure materi- included in a total approach to the emergency power generator. als that meet the requirements of ASME design of elevator systems that can 10. All elevator lobbies should A17.1. Sprinklers would rarely operate be used safely for evacuation during have access to a pressurized stair- from that location, and if they did, would fire emergencies, will enhance fire way without [the occupants] passing be ineffective and would raise havoc with fighting operations, will reduce through another fire area. the elevator controls in the hoistway. costly fire damage to elevators, and 11. All elevator cars should have 0 Sprinklers in elevator machine rooms will diminish the time that busi- means for two-way voice communi- are not considered detrimental to the nesses in the building must endure cation between the elevator car and safe operation of elevators. The underly- interruption to their normal rou- the fire command station. ing assumptions are that regular 212°F tines. Additional studies are needed 12. All elevator lobbies should sprinkers-not quick response sprin- to ensure that all potential events have means for two-way voice com- klers-will be installed, and if the envi- have been considered. munication between the elevator ronment is hot enough to open such a 1. The building shall be fully pro- lobby and the fire command station. sprinkler, the elevator machinery has ex- tected by a sprinkler system. 13. A program specifying the pri- ceeded its temperature limits and proba- 2. Elevator shafts should be pres- ority of elevator response during fire bly would be shut down before sprinkler surized. emergencies should be developed. activation occurred. Disconnecting the 3. Elevator lobbies on all floors Technical problems to be solved main power “upon or prior to” the appli- should be enclosed, include heat, smoke, water, and elec- cation of water would then permit the 4. Elevator lobbies should be pres- trical power reliability in elevators use of a simple waterflow switch, in lieu surized. during a fire. of a preaction system. 5. Air intakes for the elevator shaft These proposals have been coordi- and lobby pressurization systems nated with the NFPA sprinkler commit- should be made from a smokefree Elmer F. Chapman is a retired chief tee so that the NFPA 13, Installation of location. of the New York City Fire Depart- Sprinkler Systems, and ASME A17.1 6. All elevator lobbies should be ment. standards will not conflict. A pending recommendation by another A17 ad hoc committee is the establish- A17 Elevator and Escalator Committee tion can be used for fire evacuation. ment of “impending over-temperature” did not want to expand into panel speci- 0 Wher research concerning the ex- (IOT) at 5°C below that of the critical fying, it persuaded the NFPA 72 Pro- tent of the water problem and develop- temperature (CT) of the microprocessor tected Premises Committee to do so. This ment and evaluation of potential solu- controls. If this recommendation is has been proposed by the NFPA 72 Tech- tions are needed. adopted, each control cabinet will have nical Committee and approved by the 0 While elevator evacuation technology two safety thermostats, one to return the NFPA Signaling Systems Correlating may primarily be aimed at sprinklered car to the designated level (normal Phase Committee for final association action at buildings, information about elevator I elevator recall) when the IOT is the NFPA Annual Meeting in Orlando in protection in unsprinklered buildings reached. If the temperature then drops, May 1993. also is needed. the elevator automatically will go back 0 The application of elevator evacuation into service. If the temperature rises to Local actions taken for disabled people only is much simpler the CT, power will be cut immediately In September 1992, NIST held a work- than for the general population and is the and will require manual reset, as it is at shop on elevator use during fires. Dr. next logical step. Based on what is present. When the controls are in the Jack Snell, deputy director of NIST’s learned in this step, an application for the range between the two temperatures, the Building and Fire Research Laboratory, general population could follow. car holding in Phase I will be available opened the workshop, which was con- In November 1992, a meeting hosted by for Phase 11 fire fighters’ service, but it ducted by Dr. John H. Klote, head of an engineering firm was held in New will have a new signal light to warn of the NIST’s building fire physics group. York City for the city’s building and fire possibility of immediate shutdown, a fea- Klote’s summary of the meeting fol- officials and members of the A17 Emer- ture not now available. lows: gency Operations Committee. The fol- It has been accepted practice to con- 0 The fire protection community should lowing subjects were among those dis- nect smoke detectors required by A17.1 have the ability to use elevators for fire cussed: for elevator recall to the building fire evacuation as one of many tools-such 0 In the past, New York City permitted protective signaling system, where one is as sprinklers and compartmentation-to sprinkler waterflow switch control of el- in place. There is currently no provision protect people in new and remodeled evator recall in fully sprinklered build- for an annunciation panel for elevator- buildings. An elevator to be used for ings, rather than smoke detector control, recall smoke detectors in buildings that evacuation should be protected from basically because of past experience with lack fire signaling panels. Because the heat, smoke, and water. Phase I1 opera- many unwanted alarms from sensitive

MFPA Journal May/June 1993 51 .. r ; ,. . 8 ,

detectors. Members of the A17 Emer- they wait, if the automatic elevator sys- gency Operations Committee stressed tem can be “fire-hardened” sufficiently to An Impact Resistant, the great improvements that had been provide safe automatic service, at least made in detector selective sensitivity, until fire fighters arrive? What assurance Fire Rated cross-zoning, and alarm verification, as is there that fire fighters know the loca- Glazing Alternative well as the inherent delay in ordinary tion of people who need assistance? sprinkler operation. It was noted that New York City now requires two cross- Current stdus of the situation zoned detectors in each elevator lobby. and future expec)cltionr Most important, according to most At the present time, the situation is in a members of the committee, was the need state of flux. The problem will not go for the recall signal to come from the away. The question is: How long will elevator lobby, not from somewhere else solving it take? on the floor. No one at the meeting could At the moment, we have a new, ex- recall any building with a sprinkler sys- tremely broad federal law-the ADA- tem zone that was restricted to elevator with enforcement power vested in DOJ lobbies. Such a system, with fast re- attorneys whose knowledge of existing sponse sprinklers, might be ideal but not building codes-and more important, the cost-effective, particularly in light of re- reasons for them-may be limited. cent improvements in smoke detector At the same time, there has been a lot systems. of activity by the elevator industry, at 0 Water, either from sprinkler actuation least through the main committee and or from hose streams, is a major concern many subcommittees of A17. But eleva- in regard to operational reliability of ele- tor manufacturers are aware that the vators. A broad-based committee with longer elevators are kept in service dur- members from the A17 Emergency Oper- ing building emergencies, the more likely ations Committee and New York City fire is the possibility of real or perceived and building departments has an ongoing incidents involving equipment malfunc- program to locate and prepare a site in tion, which could lead to litigation. which to test the water sensitivity of There is encouraging closer coopera- elevator elements in hoistways under tion between the ASME A17 committee controlled test conditions. There is a vital and the NFPA 13 and 72 committees, but need to know more about this situation, there are also many local codes and Sbr SprinkleB And which may be the weakest link in safe practices that are slow to change and Lexan” Sheet Glkzing elevator operation under fire conditions. continue to conflict with well-developed Elevator-door designs are being reviewed consensus standards. Make An Excellent to restrict the of water into the Another advantage that has been at- Combination hoistway, in place of expensive, water- tained is the generally nationwide re- proof elevator equipment in the hoist- quirement that all new high-rise buildings For institutional applications where way. be sprinklered. But until a building, old or safety and security are a must, Lexan 0 Control cooling is a subject that is not new, is fully sprinklered and its sprinkler sheet is the material of choice over widely understood. Fire department offi- equipment is frequently inspected and cials sometimes turn off building power tested, there will continue to be a poten- wire glass and ceramics. And when when they arrive at the fire scene, per- tial for substantial smoke emergencies. used with a Star PH-2 institutional and haps unaware that this action reduces Because the elevator industry was a tamper resistant sprinkler system that both the reliability of the elevators and major contributor to and beneficiary of uniquely wets down and keeps the the time available to use them under the development of skyscrapers, it is Lexan sheet intact for up to two hours, emergency power. The need for some being looked to for leadership in substan- you get the excellent combination method of control cooling that is inde- tial enhancement of elevator reliability of impact resistance plus a fire rated pendent of all building power during an during building emergencies. But the el- emergency is apparent. evator industry cannot do the job alone. alternative. 0 Current practice in New York City All those who are affected by and inter- Choose a Lexan SheeVStar Sprinkler- encourages immediate elevator recall, re- ested in the solutions will have to help in Assisted Glazing System for your gardless of the point of water flow. This order to meet this goal. next school, hospital or correctional reserves the elevators exclusively for fire All in all, there is an interesting decade department use, and all evacuation by ahead of us. Is, facility. For more information, call elevators is supervised by fire depart- (414) 769-5500. Or write: Star ment personnel. This early recall signal Sprinkler Corporation, 307 W. Layton from areas that may be remote from the J. Brooks Semple is president of Smoke/ Ave., Box 51 1, Milwaukee, WI 53201. elevator lobbies appears to be in conflict Fire Rise Management, Inc. in Warren- BTAR with the spirit, if not the letter, of the ton, . .He is a member of the 5PfflNKLER ADAAG. NFPA Smoke Management Systems, Ini- COffPORAT#ON 0 It was pointed out that the elevator tiating Devices for Signaling Systems, industry is promoting elevator accessibil- and Fire Investigator Professional Qual- ity, not “egressibility.” The industry pre- ifiations committees, and is an alter- fers the status quo, rather than having the nate on the Household Fire Warning mobility-impaired wait in areas of rescue Equipment Committee. He also is a assistance on stair landings until fire de- member of the ASTM A17 Elevator partment personnel arrive. Why should Emergency Operations Committee. Circle No. 025 on Reader Service Card 52 May/June 1993 NFPA Journal