FACTORY FIRE: IT WAS LIKE “A PLASTIC PUP TENT”
FIRE REPORTS
The 21,000-square-foot building had insulation fixed to the underside of a steel roof. Then the insulation was covered with rolls of plastic. When the fire started, it was impossible to stop . . .
photo courtesy of the Record Herald. Waynesboro. Pa
Just before the 3:30 p.m. quitting time last March 19, employees at Parnell Industries in Mercersburg, Pa., a manufacturer of precision machined parts, heard a loud popping sound. A plastic air line in the cockloft had been ruptured by a fire that had been spreading undetected inside a wall and overhead.
It was not going to be an easy fire to contain because of several construction features.
The total building, 90 feet wide by 240 feet deep, consisted of two identical gable-roofed structures one story in height. A two-story concrete block office addition, 90 X 20 feet, was under construction and attached to the front of the manufacturing buildings.
The one-story building was wood-frame, metal-clad with prefabricated light wood triangular trussing supporting a metal roof. A fiberglass-type insulation was fixed to the underside of the steel roof and then covered with rolls of plastic. When standing in each of the open cockloft areas, the effect was that of a giant plastic “pup” tent in each of the two manufacturing structures.
The 10-foot ceiling in the manufacturing area was covered with 4X8 sheets of Vs-inch fiber pegboard. The peg holes were ⅛ inch in diameter and open to the cockloft areas. In the rear wall of the gabled structures, there was a 6 X 6-foot louvered vent in the apex of the gable ends of each cockloft area. The open peg holes provided a ventilation effect for air flow from the manufacturing shop floor area up into the open cockloft and out through the large louvered vents in the end walls.
Under each vent on the ground floor was a large truck door, each of which was open during the fire. Another open truck door was midway along the east wall. The door at the end of the east wall (sector C) was closed.
A stainless drain trough 5 X 220 feet long tied the two metal roofs together about 12 feet above ground level. The adjacent walls under the trough were removed, forming an open shop area 90 X 220 feet long. The shop floor was concrete. There was a small office area in the left front corner of the manufacturing area (sector A).
The building was accessible to apparatus on the front and east sides. At the rear, there was a 30-foot paved area which included raw materials and hydraulic oil drum storage.
Thirty-five feet to the west, there was an exposure consisting of a metal-clad 100 X 200-foot building used to fabricate modular homes. It was closed at the time of the fire. Its gable roof was of composition asphalt shingles. This structure was later to be threatened by a change in wind direction.
After the first popping sound, workers on the shop floor (sector D) looked up through the pegboard ceiling to see flames along the front side in the cockloft. Several employes discharged chemical extinguishers at the ceiling. The plant president and other employees went upstairs into the open cockloft. They saw fire coming up from behind the base of a trussed span.
Fast accumulating smoke conditions prevented them from advancing more than 25 feet toward the fire, which was 100 feet away.
How it began
Earlier, about 1:30 p.m., a welder had been sent outside to the topside drain trough to weld an end plate onto the trough so that water could not flow into the wall of the new office building. The end of the trough was directly over the top of a double corrugated steel wall. The corrugated wall sheets were separated by 2X4 wood framing. Fiberglass paperbacked insulation with a plastic vapor barrier was between the walls.
As the 2 X 6-foot stainless steel end plate was being welded, the hot molten steel was dripping from the underside of the trough due to burn-through. It was assumed that the hot metal found its way down through the corrugations of the steel wall to the baseboard. A 2-foot section was entirely charred through to the concrete floor footing area.
Photo courtesy of The Public Opinion, Chambertburg, Pa
A distinct V-shaped burn pattern was evident on the burned-away horizontal 2 X 4 wooden wall spacers from the floor to the top of the wall. Of course, the smoldering fire was hidden from view on the main manufacturing shop floor.
One employee who used a fire extinguisher was a deputy chief in the St. Thomas Township Volunteer Fire Company, which was to be the first-due mutual-aid company.
First call = third alarm
The deputy chief went to his pickup truck in the parking lot and initiated the alarm by radio. He asked for a third box alarm, activating eight fire companies and 19 pieces of mobile equipment. All the companies are volunteer. Chambersburg and Mercersburg each responded with one apparatus and a paid driver. All alarms are radio — dispatched by Franklin County Central Control in Chambersburg, the county seat of government.
The alarm was received at 3:33 by the Mercersburg, Montgomery, Peters and Warren (M.M.P.W.) Volunteer Fire Company, housed in Mercersburg one half mile from the fire. The centrally located Mercersburg and the three adjacent townships pool their tax monies to partially support the M.M.P.W. company, which protects 150 square miles and a population of approximately 10,000 in a rural setting. The closest mutual-aid company was 8 miles, while the most distant company was 18 miles over rolling farm land.
M.M.P.W. Company 9 responded immediately with two engine-tankers, one paid driver and three volunteers. Upon arrival, heavy smoke was coming from the front side blowing over Churchill Road 75 feet away. The roof-wall junction showed lesser smoke conditions on either side. Smoke was evident from the louvered vents to the rear. There was a slight northwest breeze blowing toward the south.
The first engine-tanker dropped its 2 ½-inch preconnected four-way hydrant valve and gated wye at the 800-gpm hydrant on the street in front. It laid 300 feet of 3-inch supply hose midway to an entrance door on the right. A 1 ½ -inch preconnect was pulled by a fire fighter employee of Parnell. The paid driver charged his pump and donned an air mask while the 3-inch supply line was being hooked into the 1500-gallon tank. The apparatus has a 750-gpm pump.
On the street, the second engine-tanker, which carried all the rescue equipment,was connecting to the four-way valve. That apparatus carried 1000 gallons of water and had a 750-gpm front pump. Smoke conditions were very severe at the hydrant, junior fire fighters laid a 2 ½-inch line along the exposure.
At the same time, Fire Chief Charles Snyder arrived on the scene and ordered the 4000-gallon tanker to take the rear side. That apparatus had a 1000-gpm frontmounted pump with preconnected monitor nozzle mounted on the bumper top plate. A preconnected 2-inch line was directed into the rear door of sector C which was heavily charged with hot smoke.
Casualties feared
Snyder became a walking command at this stage of the incident. Seeing a 1 ½inch line inside a doorway, Snyder asked the driver who had it. The driver, who had just donned his mask, did not know. The chief and the driver crawled 10 feet into the doorway and yelled for the hose man. They tried to pull the hose line, but it could not be moved. There was no answer. Heavy fire came down from the ceiling, forcing them out. The chief ordered the preconnected deluge gun into the opening since the top-mounted deck gun could not get the angle for effective interior attack. Bystanders helped to pull the deluge set to the opening.
Snyder turned to get additional help for the rescue attempt. A crying woman stopped him and asked if her husband was still in the burning structure. The chief was sure a man was down.
His fears were relieved when the presumed missing fire fighter was reported safe after having given up the line when the ceiling started to drop. No one apparently saw him exit the building. The hose and nozzle burned.
Fire conditions intensify
The chief went to the rear and ordered the tanker repositioned in front of the door in sector B where welders’ tanks were reported.
The monitor nozzle directed a stream into the louvered vent of sector B. Conditions were intensifying. At this point, the deluge set was delivering 400 gpm into the shop area midway up the east side. The monitor gun on the tanker was delivering 550 gpm into the cockloft and floor area of sector B.
Volunteers were arriving. The first mutual-aid tanker from St. Thomas Company 8, 8 miles away, supplied the rear operation with an additional 1800 gallons of water into the Company 9 tanker. The entire cockloft was blowing fire, and ceilings had dropped in sectors D and C. Volunteers were pushing drums of oil away from the storage area.
Snyder appointed St. Thomas chief 18 as water supply officer for the drafting operations to be set up at a stream 300 feet away. The two Company 18 enginetankers set up a relay protecting exposures. The engine at the stream laid three 300foot 3-inch supply lines. All fire fighting was developing into a defensive mode.
Then the roof collapsed with the metal outside walls remaining intact. It was estimated this took place within 20 minutes of arrival.
The St. Thomas deputy chief was given command of the rear. The assistant chief of Greencastle Company 3,11 miles away, was assigned the front with orders to protect the files in the office area of sector A. This action saved the payroll. Many filed papers were charred on the edges within the steel files, but they were saved.
Marion Company 8, 15 miles away, supported the Greencastle 2100-gallon tanker and 1000-gallon engine-tanker with their own 3100-gallon tanker trailer. Two 2-inch lines were laid to the front.
Two engine-tankers and an 85-foot tiller aerial arrived from Franklin Rural Volunteers of Chambersburg, 18 miles away. Their driver set up an 1800-foot relay operation from the stream to the east side. He used the two Franklin apparatus and a Marion apparatus to complete the layout to supply an 85-foot ladder tower from Chambersburg Boro.
McConnellsburg Volunteer Fire Company moved up from standby in the M.M.P.W. fire station to lay a line from the front hydrant to supply the aerial pipe on the tiller-aerial which was located at the corner of sector C.
Wind conditions change
Wind conditions were changing. Snyder had the preconnected deluge set relocated to protect the west exposure and the electric service at the side of sector A between the fire and exposure building. The tower ladder was just getting into position at the front corner of the exposure. The relay was almost set up from each of the drafting locations to feed the tower when the fire and smoke blew toward the exposure. The two 1 ½ -inch hand lines were withdrawn as a safety precaution. The electric company had not arrived yet to cut the power.
The ground deluge was played onto the fire from a lower level shipping area of the exposure. At that point, the tower ladder played water from the basket onto both structures, including the electric service protection which was by then deactivated by the power company.
Company 9 set up its 37-foot utility aerial at the corner of sector D as a vantage point during the duration of the wind change.
Two deputy chiefs of Company 9 handled fuel supply and salvage of office records. One-third of the apparatus was diesel and did not require fuel on the scene. The gasoline apparatus required fuel, which had to be carried in 5-gallon cans because a fuel truck was not available.
A Franklin County Fire Chiefs Association air cascade unit supported the fireground operations, generating air with its 1700cubic-foot compressor.
The electric service transformer platform was saved along with exposure 2. The computer-operated machines were lost. Estimated damage was $2.4 million, partially covered by insurance. Many loads of fabricated parts were salvaged.
Observations
The following observations were discussed after the fire:
The structure had no hose lines for fire protection; nor did it have an alarm system. A staging area was not required because apparatus arrived in staggered time intervals due to distances traveled.
Louvered vents on side 3 prevented efficient master stream application into the cockloft areas.
There was considerable water runoff during the height of the fire which headed for the stream on the south side, but it could not be handled due to lack of manpower and proper equipment.
There was a time delay in getting the preconnected master stream into operation on side 4 due to the attempted rescue effort and lack of trained manpower. The deluge should have been first water on the fire.
Based on 15 percent involvement upon arrival and using the National Fire Academy’s modified cubic foot water flow formula, 1700 gpm would have been initially required for control. The actual water delivered in the first five minutes was 100 gpm. Within the next time period between 6 and 10 minutes, 950 gpm was being delivered but not efficiently applied due to louvered vents and falling ceiling. The involved area was steadily increasing to an estimated 50 percent or more after 6 to 10 minutes of arrival.
Approximately 80,000 gallons of water were pumped into the structure. A new building has been built on the same foundation.
