BY TRACY J. RAYNOR
Over the years, a strip mall structure may have a number of occupancies and undergo many construction changes. One such strip mall in Boise, Idaho, has had many transformations over its lifespan, including three major fires (photos 1, 2). On the evening of June 15, 1985, the first fire struck, starting outside the structure in a trash bin and eventually extending into the attic through the eaves. The occupancy in this area of the strip mall was a large, open-area grocery store at 6523 West Ustick. Although contained to the grocery store occupancy, the fire did extensive damage to the roof and attic areas, including smoke damage throughout the store itself. The store never reopened for business after this fire.
After the late 1980s, the strip mall had several owners and business ventures. The grocery store was later a warehouse for a bridal/tuxedo outlet (the largest occupant), which had a retail outlet located elsewhere in the mall, along with other smaller shops.
(1) Photo by Captain George Webb.
(2) Photo courtesy Boise (ID) Fire Department.
AUGUST 8, 2002, FIRE
At approximately 2016 hours on August 8, 2002, the Boise (ID) Fire Department responded to a reported trash fire in the rear of Treasure Garden at 6521 West Ustick, located in the west end (D side) of the strip mall. The dispatch center upgraded the assignment to a full structural response after receiving a report that the fire had extended into the eaves of the structure. Boise’s standard commercial structural response includes three engines, one truck, one battalion chief, and an incident safety officer.
The first unit on-scene, an engine company, reported fire in the rear extending into a large commercial structure and requested a second alarm. Boise’s second alarm consists of two additional engines, one truck company, one battalion chief, and a command page for chief officers.
The engine positioned at the C/D corner of the structure and extended a 13/4-inch line to extinguish the exterior fire and check for extension into the structure. Another engine and one truck company gained access to the front (A side) of the structure, conducted a primary search, and checked for fire extension into the structure using a thermal imaging camera. The truck officer initially reported that the interiors of the two businesses on the strip mall’s D side (6521 and 6517, the bridal/tuxedo outlet) were clear, but it appeared the fire was in the attic area of the C/D corner.
The first-arriving engine was working in the rear of the structure in the eave area and reported fire in the eaves. Command assigned a truck company to the rear (C side) of the structure to assist the engine with exposing the eaves and checking for fire extension. An additional engine was assigned there and used a five-inch large-diameter hose (LDH) to provide a continuous water supply to the other engine (photos 3, 4).
Another engine arrived on-scene and was assigned as the rapid intervention team (RIT).
Two second-alarm engine companies arrived and were staged. Interior companies reported fire in the attic areas of 6521 and 6517 and that it was making a run to the east. Command directed one second-alarm engine company to supply water to a first assignment engine and that both crews advance lines to the interior from the front of the building.
The interior truck crew started pulling the ceiling in 6521, and a second alarm engine was assigned to 6501 (a sports memorabilia shop) to check for fire extension in the attic.
As the incident escalated, Command designated the two engines and one truck unit operating at the C/D corner as Division C. At this time, Command requested a third alarm, bringing two additional engines and a battalion chief.
After completing the water supply duties, a second alarm engine joined another to advance 21/2-inch handlines into 6501 from the front of the building and stop the advance of the fire in the attic. The two engine crews pulled the ceiling in 6501 and set handlines in place to stop the fire. The truck unit from Division C was reassigned to the roof to complete a ventilation assessment.
Interior companies reported heavy fire in the attic to the rear of the first two occupancies (6521 and 6517) on the D side. The Division C engine companies initiated a fire attack from the rear into 6517 and were able to contain the fire to the attic and stop its progress to the east. The roof truck company started ventilation operations on the roof to assist in stopping the fire’s spread.
(3, 4) Photos by Captain George Webb.
One third-alarm engine was assigned to advance a handline into the A side of 6517; a truck unit was pulling the ceiling in this occupancy and encountered a heavy volume of fire in the attic. Another third-alarm engine was assigned to assist the roof truck company with ventilation operations. The roof truck unit reported to Command that its inspection cuts were now starting to show a knockdown on the fire.
Support personnel were en route with SCBA bottles and rehab for on-scene personnel. Command conducted a roll call and confirmed the status of all units and that all crews were intact.
With the aggressive interior fire attack, the attic fire was confined to the 6501 and 6517 occupancies, and Command declared the fire under control at 2140 hours. Units remained on-scene for several hours, conducting extensive overhaul and salvage operations; the last unit was released from the scene the next morning at 0747 hours. Fire investigators remained on-scene to determine the fire cause.
SEPTEMBER 6, 2002, FIRE
On September 6, 2002, at 1615 hours, the dispatch center received a report of an unknown type of fire at the strip mall’s 6427 occupancy, the Agape Christian Worship Center. A single engine was dispatched; additional information dispatch received stated that flames were seen coming from a fan located in the worship center. On receiving this information from the dispatcher, the engine company officer requested a full structural response assignment. The first assignment incident safety officer arrived at 1620 hours and reported a single-story strip mall of ordinary construction with smoke showing inside the structure and from the attic area. He assumed command and requested a second alarm.
Command observed a number of occupants still inside the strip mall, announced a rescue mode, and assigned an engine and a truck company to start evacuating the occupants from the front of building. Another engine arrived and was assigned to provide water supply to the first-arriving engine on- scene.
The division chief of training and safety arrived at 1626 hours and assumed command from the incident safety officer. Command directed an engine to the C side (the rear) of the strip mall to provide egress for crews entering from the front. This engine reported the rear of 6427 was open with occupants still inside and heavy smoke issuing from the rear. This engine crew also assisted in removing occupants from 6423, the bridal/tuxedo outlet. After the August 8 fire, the bridal/tuxedo outlet had moved its retail showroom at 6517 and combined it with its warehouse area at 6423.
Another engine arrived and was assigned as the RIT on the A side. Crews working on evacuating the 6423 occupancy reported it was all clear; two engine companies began the fire attack in the worship center (photo 5).
An arriving truck company was assigned ventilation assessment. Interior crews reported fire in the attic that was moving toward the B side of the strip mall. Command requested a third alarm at 1634 hours, which brought two more engine companies.
The truck company performing evacuation reported an “All Clear” on the primary search for all areas except the immediate fire area, 6427. Crews operating in the fire area encountered high heat and had two lines in operation. Crew rotation became critical at this point, since as interior crews came out to exchange air bottles, other crews were needed to replace them inside.
The roof truck company started roof ventilation operations to relieve the high heat and smoke buildup in the worship center and also reported fire showing from the site of a vent hole on the D side of the occupancy, originally made during the August 8 fire. The hole had been covered with plywood after that incident.
(5) Photo by Captain Parker Sheehan.
(6) Photo by Captain George Webb.
The roof truck company continued to support the interior crews that were advancing lines to the rear of 6427, where they reported heavy fire in the rear. The first-arriving engine was designated the interior division, encompassing the bridal/tuxedo outlet (6423), the worship center (6427), and the sports memorabilia shop (6501). Three additional engine companies were assigned to the interior division under the first-arriving engine company’s officer. With the report of heavy fire still in the rear, Command re-quested a fourth alarm at 1655 hours, which brought two more engine companies.
Rehab was established; crews were rotated through and medically monitored prior to being assigned.
The roof truck company completed the ventilation hole to the rear of the worship center. The interior crews reported the smoke and heat were lifting and started advancing a 21/2-inch line on the fire. Companies assigned to the bridal tuxedo outlet (6423) and sports memorabilia occupancies (6501) reported little extension into these occupancies, except in the attic areas. At 1732 hours, the fire was declared under control. Engine crews remained on-scene until 0028 hours the next day, performing overhaul and assisting the fire investigators.
Preplanning. Building layout, construction type, and feature information that fire personnel obtain during a walk-through inspection is invaluable during a fire. All considerations play a critical role in the outcome of an incident. It is important that the building information be current and provided to all responding companies in the district.
Roof construction. Identifying the roof construction type is critical for roof operations. This determines whether the roof team can operate on the roof and, if so, for how long. Is the roof wood joist, lightweight wood truss, open-web steel bar joist, or bowstring truss? Each type has its own collapse potential and safety factor for operating on it and behaves differently under fire conditions. The roof team must have a good understanding of this.
Roof teams also play a valuable role in communicating building information to the incident commander, relaying building size, roof loading and types, and construction features such as firewalls and parapets. Keep in mind the collapse potential for parapets: The sidewalk in front of the parapet wall is in the collapse zone and the doorway does not provide refuge.
General collapse warning signs. All members operating at a strip mall fire should be aware of the structure’s condition and watch for the warning signs of collapse. In addition to heavy fire involvement, note the following indicators:
- walls showing cracks, movement, bulges, and smoke coming through the wall;
- floors with holes, overloading, and sagging;
- beams that pull away from supports; and
- columns that are out of plumb.
Opening up ceiling. Crews operating at fires involving strip malls or any large commercial structure should open up concealed plenum space to check for fire extension. This should be among the first tactics on entering the structure and should assist in eliminating the possibility of fire dropping behind crews as they advance deeper into the building.
Thermal imaging cameras. TICs are excellent tools for locating potential fire victims and the seat of the fire and fire spread in the structure. However, companies must not forget the basics and be properly trained in the use of TICs. These devices are just another tool, not an all-purpose solution; the basics are essential. All 14 engines in Boise carry a TIC, and the truck companies each carry two.
Safety issues. Opening egress points is a critical fireground tactic. Companies entering from the front of the structure must have a secondary means of escape—e.g., the doors located at the back of the structure. On larger structures, command should consider using multiple rapid intervention teams. Large open areas are prone to collapse when fire is in the attic area, so be prepared. Address fire travel in false fronts early in the incident.
Be prepared. Line selection and placement are critical to the overall incident outcome. Proper placement should be as follows: first line on the fire, second line as a backup, and third line to the most threatened exposure. If you have a fire in a big building, choose a big line. This will give you, not the fire, the advantage.
(7, 8) Photos by author.
STRIP MALL CONSTRUCTION
Roof. The strip mall was of ordinary construction with large laminated beams set on masonry block wall columns; beams were spaced approximately 12 feet apart. 2 2 12 wooden rafters ran parallel to the long axis of the building; they were placed on top of the beams, which assisted in fire spread in both incidents.
Ceiling. The building had multiple ceiling types throughout. Drop ceilings in the west-end (D side) occupancies provided large void spaces in the attic area. The ceiling in 6427 was attached to the underside of the 2 2 12 rafters; this made for a very high ceiling that contributed to the extremely high temperatures experienced in this occupancy (photo 6).
Compartmentalization. The mall had very little compartmentalization. Small storage areas to the rear and party walls were used to break up the large open-area design of the strip mall. Steel doors in metal frames set in masonry were located in the rear of the structure. Glass storefront windows made up the majority of the front of the strip mall. The original strip mall had no firewalls in it. There was a masonry wall extending just to the ceiling between 6501 and 6427. None of the other occupancy separations extended beyond the ceiling. The resulting common attic space made this older strip mall more vulnerable to rapid fire spread.
New truss roof. Because of the August 8 fire damage in the attic area, the complete roof assembly was replaced with a lightweight truss system. This consists of two trusses, one extending from the rear of the structure 49 feet to approximate center (photo 7) and the second truss extending 57 feet 7 inches from center to the front of the occupancy (photo 8). We now have a large truss loft that can spread fire rapidly as well as cause the roof to fail early in the incident.
TRACY J. RAYNOR has more than 25 years of fire service experience and is the division chief of training and safety for the Boise (ID) Fire Department. He has served on engine and truck companies and also on the hazardous materials team. Raynor has developed company officer development and other training programs and has taught for four years as an FDIC HOT instructor.