Photo by Steve Groer
DENVER’S POLO CLUB CONDO FIRE: ATRIUM TURNS HIGH-RISE CHIMNEY
On October 31, 1991, the Denver Fire Department responded to an unusual and challenging fire in a residential high-rise building that yielded significant lessons, particularly about fighting fires in buildings constructed with large, open atrium spaces.
At 0805 hours that day, the DFD communications center received a report from a central station monitoring agency of a fire alarm activation at The Polo Club condominiums at 3131 East Alameda Avenue in South Denver. With no additional calls confirming a fire, a reduced response of one engine company, one truck company, and the district chief was dispatched.
Temperatures were well below freezing. Snow was on the ground, and there were snow flurries throughout the city. Winds w ere gusting out of the north at approximately 10 to 15 mph.
THE BUILDING
The Polo Club, built in 1967, is a 165by 107-foot, 20-story building containing 150 condominium units and approximately 250 residents, the majority of whom are senior citizens. Each unit totals approximately 1,000 square feet in area. It is a fire-resistive steel structure with poured-concreteover-metal-deck floors and masonry exterior walls. At the time of the fire, steel structural members were protected with asbestos; building management has since undertaken a program to replace that with a more suitable protective material.
A 93by 46-foot atrium runs through the core of the building for its entire height, terminating in 28 skylights that protrude like small pyramids above the roof level. Two manually operated louvered smoke dampers are located within the metal atrium roof frame. Public hallway balconies serving the tenant spaces are open to the atrium. The building is not equipped with a central HVAC system.
A bank of three elevators on the building’s east side services all floors. There are two enclosed stairshafts in the building located at both the east and west sides.
Only the basement area is equipped with an automatic sprinkler system; both this and the building’s wet standpipe system operate on municipal water supply and are pressurized by the building’s 1,500-gpm fire pump. There is a six-inch standpipe riser in each of the stairwells, and both 2 ½-inch and 1 1/2-inch connections on each riser. It had been a Class III standpipe system before house lines were removed by the fire department and the system designated for department use only. Standpipe connections on lower and middle floors are equipped with pressure-regulating valves.
Pull stations, located at each exit area, are connected to a central station alarm monitoring company. Pull station activations are indicated on the lobby’s fire annunciator panel (there is no fire control room). Smoke detectors in residents’ apartments provide local alarms only. Ill ere are no other fire alarm/detection systems in the building.
Door frames around self-closing, one-hour-rated residence doors were provided with smoke and draft control assemblies; this proved a significant building feature in this incident.
OPERATIONS
The first-arriving engine company reported no sign of a fire or smoke condition in the building, both from the exterior and the lobby area. The annunciator panel in the lobby/atrium area indicated a pull station activation on the seventh floor. Firefighters proceeded there to investigate, and the building manager directed them to apartment 702. From the hallway there was no indication of fire within.
Firefighters opened the apartment door and were hit with heavy heat and smoke. The company officer communicated the situation to Assistant Chief Michael Miller, already on the scene, who in turn assumed command of the incident, requested a full task force response (upgrade to first-alarm drant. At no time in the operation was water supply to be a problem.
(Photos by Harold W. McCann.)
The initial attack, made with a 1 3/4-inch line and combination fog nozzle, was turned back by the fire, and in just a short time the heat broke out apartment windows. This introduced fresh air to the fire and created a wind tunnel of heat and smoke flowing through the apartment into the atrium with blowtorch force. Firefighters were forced to retreat into the hallway. Thick, black smoke poured out of the apartment into the atrium area.
IC Miller’s initial strategic objectives were clearcut—address the life hazard in the apartments above and next to the lire apartment, aggressively attack the lire, vent the atrium, and address resident control in areas above but remote to the fire —but assignment for a full complement of three engines, two trucks, one reserve company, and two district chiefs), and directed first-arriving truck company members to reconnaissance and search and rescue of the fire floor and the floor above. He obtained building floor plans and ascertained that there was no central HVAC system in the building. Meanwhile, the engine company connected its line to the standpipe in the west stairwell and prepared to attack the well-advanced fire. The engineer/operator, as per SOP, stretched a supply line to the Siamese connection as the first step of a tandem pumping operation to augment the building water supply; this would be completed by the second-in engine company, which accesses a city hywith less than a full-alarm assignment dispatched at the outset, operations already were in a state of catchup. After confirming that they had accounted for the life hazard in the immediate area surrounding the fire on the seventh and eighth floors, Miller quickly assigned his only available truck team to vent the smoke that was beginning to bank down from the atrium skylights. The louvered smoke dampers were opened but proved quite incapable of handling the volume of smoke produced from this single apartment fire. The atrium quickly was becoming a smoke reservoir that could threaten residents above the fire. Miller ordered that elevators be taken out of service because this shaft was open to the atrium and becoming contaminated with smoke.
Miller made certain that the stair shafts provided access to the roof level, then ordered the lobby area cleared for the roof vent operation. All firefighters on the roof operated with lifelines tied off to substantial objects. Hand tools were used to break the plexiglass skylights.
The vertical vent operation was difficult and dangerous: The spaces between the pyramid-shaped plexiglass skylights were narrow and covered with snow; the pyramid shape of the skylights did not afford any better footing; winds were strong; there was no parapet wall around the atrium section of the roof; and heat and smoke that poured out of the vent openings made negotiating the roof even more difficult. However, this tactic was absolutely necessary to relieve the atrium of heat and smoke buildup.
TASK FORCE ARRIVAL
The arriving task force companies filled critical gaps in strategy and tactics. The tandem pumping operation was completed, and firefighters placed 2/2-inch handlines with 1⅛inch smooth-bore tips into operation both at the point of attack and on the floor above. Vertical spread through autoexposure was now a serious threat since fire was blowing out of the apartment in an uncharacteristic blue-colored flame at times some 15 feet beyond the balcony and reaching for the floor above.
Additional firefighters were assigned to assist the roof ventilation effort. Others were directed to form reconnaissance/messenger teams and communicate with residents, providing reassurance and instructions that they were to stay inside their apartments with their doors shut unless directed otherwise by fire department personnel. (Fortunately, each unit had an exterior balcony area for refuge.) Residents not contacted in person were notified of the situation by telephone. Miller designated Assistant Chief John Giese to direct extinguishment operations and monitor conditions on the fire floor.
(Photos by Harold W. McCann.)
Companies operating on the fire floor made several attempts to advance into the burning apartment and reach the seat of the fire. However, even with more than 400 gpm flowing at the point of attack, the extreme heat from the fresh-air-fed fire that vented into the atrium continually turned back firefighters.
Progress of the outside vent teams was slow in comparison with the amount of smoke generated by the fire. In a short time it was banking down quite low—as low as the fire floor before vertical ventilation was accomplished and effective. There were approximately 150 people above the fire, most of whom were elderly. Based on reconnaissance reports from firefighters; the ages of the residents; the relative smoke-free condition in the apartments; the considerable smoke contamination of the stairwells, which had been opened up on the fire floor for attack operations; and the number of on-scene personnel, Miller decided not to evacuate residents at this time. With no headway being made on the fire and smoke continuing to be a problem in vertical shafts, command explored the possibility of an aggressive outside attack with an aerial master stream; unfortunately, an underground parking facility on the building’s north side made that impossible.
At 0822 hours, Miller called for a second-alarm assignment plus two additional truck companies, based on status reports from operations sector commander Giese. This second-alarm assignment, in addition to needed personnel, brought a mobile highpressure air supply unit and a haz-mat/ command vehicle to the scene. Miller also requested that a mobile communications van be brought in. Equipment and personnel staging areas were established on the sixth floor, and additional companies moved fresh air cylinders and other equipment to that area. Logistics and safety officers were assigned by the incident commander. The additional truck companies were assigned to positivepressure ventilation of the smokecontaminated stair shafts. Meanwhile, with several atrium skylights broken out, the atrium literally had become a chimney.
CONTROL
With efforts to control the fire still unsuccessful, Miller faced the prospect of a possible mass evacuation of elderly residents from the floors above; so much smoke had been and continued to be generated by the fire that contamination of areas beyond the atrium was inevitable. He called for a third-alarm assignment at 0840 hours for the purposes of evacuation and relief of firefighting crews.
Soon thereafter, attack companies on the fire floor made entry into the adjacent apartment and located the hottest wall in the apartment. With a charged line in operation, members breached the wall and were able to get water on the seat of the fire, allowing companies poised at the apartment door to proceed into apartment 702 and thoroughly extinguish the fire.
POSTFIRE
The unusual fire conditions created by this building construction necessitated response by approximately 100 Denver firefighters and support personnel. This included eight engine companies, seven truck companies, one rescue company, and four district chiefs, in addition to personnel from the air, haz-mat, and communication units.
The official origin of the fire was an electric blanket: The occupant of unit 702, a 43-year-old female, left the electric blanket turned on in a pile of bed linens and a rubber mattress cover. She noticed smoke coming from the blanket and attempted unsuccessfully to remove the mattress cover. Then she attempted to extinguish the fire with a glass of water. Finally, after several attempts to control the fire herself, she ran down the hall and pulled the fire alarm box.
The resident manager came from the lobby to investigate the alarm. He made an attempt to enter the unit with a fire extinguisher, but he couldn’t get near the fire because of heavy smoke. He closed the door to the apartment and escorted the occupant of 702 to the lobby area.
No follow-up calls were received by the DFD communications center until after the first companies had arrived —that first occurred at 0821 hours by occupants of another building. No solid information relative to actual fire conditions on the seventh floor was passed on to first-arriving firefighters by the building manager or occupants.
Five firefighters were injured during the Polo Club incident. These injuries ranged from smoke inhalation to burns and heat exhaustion. There were no civilian injuries and no fatalities. Excellent performances by our firefighting crews and Chief Miller’s decisive calls for assistance and implementation of strategic goals helped prevent loss of life and additional damage to the structure other than that which was unavoidable.
LESSONS LEARNED AND REINFORCED
- A fire in a high-rise building w ith an atrium w ill greatly enhance movement of smoke through the building. Meat and smoke may not necessarily vent to the outside atmosphere through exterior windows; rather, the temperature and pressure differential between the large atrium space and the exterior atmosphere could drawfirst cooler air and then, with it, buoyant products of combustion into the upper interior spaces, creating a stack effect that severely impedes firefighting operations and threatens life safety of the occupants above the fire. In addition, wind conditions exacerbate this problem.
- Traditional concepts of vertical compartmentation to limit fire spread do not apply to atrium spaces, which is the reason that national building codes impose strict fire protection requirements for buildings that have them. Buildings with atriums constructed prior to the code must be the target of tireless efforts to retrofit them with vital fire protection systems—including first and foremost (but not limited to) full automatic sprinkler and smoke-management systems. The urgency of this is underscored by the quantities of smoke generated by the Polo Club fire —a fire in a single apartment with very ordinary combustible furnishings— that posed a very real threat to occupant safety.
- Control of building systems and rapid establishment of adequate personnel and logistics support are key to successful high-rise firefighting. Firefighting forces must “become” the vital fire protection systems in cases where they do not exist.
- In this case, Denver firefighters made an extraordinary effort to vertically ventilate the atrium, becoming essentially a human smoke-management system. Aggressive atrium ventilation early in the operation was essential at the Polo Club incident. Safety is foremost. All firefighters should be operating w ith lifelines tied off to substantial objects. The operation cannot proceed until the atrium lobby is clear and roped off and the “all clear” signal given.
- Experience has shown that smooth-bore tips are more effective in aggressively attacking high-rise fires. As reinforced from previous fires, high-rise packs should include a smooth-bore nozzle, for a variety of reasons, not the least being that smooth bores can better compensate for lower pressures caused by water supply problems.
- Autoexposure from floor to floor within the interior atrium is a prime concern. Companies must be assigned above the fire floor to stop vertical spread in this fashion as well as via radiant heat.
- iTie type of structure and amount of heat generated by a single-unit fire, in addition to the life hazard, makes it essential that handlines for backup on the fire floor and exposure protection on the floor above at a working highrise fire be 2 1/2-inch lines with smooth-bore tips.
- At the Polo Club incident, in which interior positions within the fire apartment were untenable and firefighters did not have a straight shot at the fire, breaching an interior adjacent wall was the best option for firefighters to reach the seat of the
- fire. Even while maintaining an aggressive, offensive fire attack mindset, creativity and flexibility in firefighting are important.
- Aggressive positive-pressure ventilation of stair towers early in the operation provides relief for operating companies and a clearer means of egress for residents should evacuation be necessary.
- Evacuation of residents above the fire floor will be very difficult in a structure with a wide open vertical space that “shares” the atmosphere with tenant spaces. It should be avoided if at all possible. A defend-in-place strategy was necessitated at this incident due to building construction. Fortunately, extinguishment was completed before smoke contamination of upper residences forced evacuation.
- The fire service does not have much experience with atrium fires— all the more reason that thorough preplanning by first-due companies is imperative and should be made available to the rest of the department. Preplans should include all common and unique fire protection systems and design features, areas of refuge, etc.
- Occupant unit doors in large, multiple-residence dwellings should be self-closing to limit smoke contamination of other areas: Historically, occupants run away from a fire without closing the door behind them. Remember, however, that tight doors with ample smoke/draft control frame assemblies can mask signs of an intensifying fire condition within. Take a defensive posture when opening and be ready to close the door quickly.
- Fire department efforts toward public education, particularly in how to react to a fire, never can be overemphasized. Although reduced responses to alarm activations are common and necessary in many departments, the effectiveness of this plan relies totally on the reaction of building occupants. Lack of adequate information in this incident —no follow-up calls to report the fire, no communication from building personnel, etc.— created substantial delays
The stack effect in this building was virtually a textbook case: warm temperatures inside, very cold temperatures outside. Even with this windaided stack effect in place, there was a “bottleneck” of smoke movement at the top of the atrium space because smoke dampers were insufficient and ineffective.
