BY MARK COTTER
The Salisbury (MD) Fire Department (SFD) was alerted at 0917 hours on Wednesday, December 21, 2005, for an automatic fire alarm at the Maxum Yacht plant on Naylor Mill Road. Engine 1-1 responded, staffed with Lieutenant Richard Rathel, Firefighter/EMT-B Joseph Derbyshire, and Firefighter/EMT-B Christopher Rathel, son of the officer. Both the engine and its officer were specially detailed to that station for the day.
Maxum Yachts manufactures fiberglass pleasure cruisers in a 140,000-square-foot factory employing almost 200 workers. The process includes cutting wood framing and trim, laying down fiberglass and epoxy material, and painting, each of which presents distinct fire hazards. In fact, the plant has its own fire brigade, which drills regularly. Automatic alarms at the facility are not uncommon.
On arrival at the facility at 0921 hours, the Engine 1-1 crew was directed to a hopper, or silo, containing waste sawdust that was vacuumed from the plant and stored, awaiting disposal. The container, approximately 10 feet square and three stories high, was equipped with an access ladder to a surrounding catwalk located about 20 feet aboveground. On the east side of the catwalk was an access door approximately 2½ x 4 feet. The sawdust entered the hopper from the plant through a two-foot-diameter aluminum pipe. It was drawn in by a blower at the top of the silo and eventually would be emptied through a pipe in the bottom of the container to be transported away for disposal.
The silo was adjacent to the east side of the plant, approximately 200 yards from-and in a direct line of sight with-the front gate. Light smoke could be seen pushing from the vent at the top of silo. Engine 1-1 was positioned just to the east of the container, opposite the plant. Lt. Rathel and Firefighter Rathel advanced a 1¾-inch hoseline up the silo ladder to the access door on the catwalk. On opening the access door, they saw light smoke but detected little heat. The hoseline was charged, and a straight stream was directed inside the silo to wet down the contents.
FIREBALL
Several seconds later, Lt. Rathel, who was operating the nozzle, observed a wave of sawdust blowing out of the door. Quickly turning away his face and closing his eyes, he fell back and away from the door as a huge fireball erupted from the inside of the silo. Later, he said he did not even realize it was fire until he opened his eyes and saw the flames blowing over him. The entire blast lasted only a few seconds. Firefighter Derbyshire, operating the pump, was standing on the side of the fire apparatus not facing the silo. He heard a “whoosh,” walked around the pumper, and saw Rathel on his back; the fire was already subsiding. Rathel’s son, who was not injured by the fireball, immediately came to the lieutenant’s aid, and Derbyshire radioed that the engine company’s officer was down; he requested a full first-alarm assignment.
Before this dispatch was completed, additional units monitoring the radio traffic were en route. Maxum is located in the far northern end of the Salisbury’s fire district; units dispatched included Salisbury Stations 16 and 2 and Station 74 from the neighboring Delmar (DE) Fire Department to the north. Station 1 fire units, located in the southeast section of the city, remained available to cover the fire district. The first-alarm assignment from the SFD included an assistant chief, a deputy chief, two engines, one truck, one rescue, an EMS supervisor, and three medic units. In addition, a truck and a rescue company responded from Delmar. SFD Chief David See, Deputy Chief 1 Timothy Keenan, and Deputy Chief 2 William Gordy also were alerted.
On arrival, Assistant Chief 1 John Tull assumed command, setting up a command post just outside the plant gate. Lt. Rathel, with burns about his face, had been lowered to the ground using a plant scissor-jack lift operated by Maxum personnel. He was placed into a Medic 2 when it arrived shortly after. Tull ordered the arriving SFD Engine 16 to establish a water supply by laying in a five-inch hoseline from a hydrant outside the plant gate, a distance of almost 1,000 feet. The first-arriving aerial, Truck 16, was instructed to set up on the east side of the engines. Delmar Truck 74 staged on Naylor Mill Road, outside the plant gate; its crew was directed to proceed to the scene on foot. With Tull committed as incident commander, Deputy Chief 1 Keenan, as per policy, assumed the role of duty officer and informed Dispatch that he was assuming citywide command.
Medic 2 radioed that they were preparing to transport Lt. Rathel, who was accompanied by his son, to Peninsula Regional Medical Center (PRMC) in Salisbury, the local hospital/trauma center. Unfortunately, and unknown to the other firefighters on-scene, the only two witnesses of the explosion were in the back of that ambulance. The incident had occurred so quickly that not even they yet understood what had happened.
Responding members later said that they had assumed Lt. Rathel had collapsed or fallen. The newly arrived firefighters proceeded to manage the still-uncontrolled fire in the silo without the benefit of the previous crew’s experience.
The crew of Engine 16-1, consisting of Acting Lt. Christopher O’Barsky, Firefighter/EMT-B. Donald Phippin, Firefighter/EMT-B Steven Dickerson, and Firefighter/EMT-B Zachary Bridges, with Firefighter/EMT-B Ian Runkles serving as the driver/pump operator, disembarked their rig after it was positioned just behind Engine 1-1. O’Barsky, Bridges, and Phippin donned full protective gear and SCBA and proceeded up the access ladder while Runkles and Dickerson connected the five-inch supply line to Engine 1-1.
SECOND FIREBALL
Once on the catwalk, the three Engine 16-1 firefighters stretched the still-charged 1¾-inch line from Engine 1-1 to the access door, which had remained fully open since the first crew’s attack. As in the previous encounter, they observed only light smoke emanating, with no appreciable heat. Again, a straight stream was directed on the material within. Unfortunately, the result was the same as before: Another fireball blasted out-this one catching both O’Barsky and Bridges full force.
Stunned by the explosion, and with their gear partially aflame, both firefighters stumbled away, forced by the still-open door to move in the same direction along the narrow catwalk. O’Barsky slumped to the deck, lying supine with his feet dangling from the catwalk. Bridges, who was in front of and below his officer when the blast occurred, regained his bearings after rounding the corner from the doorway and removed his charred mask. With fellow firefighters shouting directions from below, Bridges returned to secure O’Barsky so he wouldn’t fall. Phippin, standing just around the corner of the silo when the fire erupted, was shielded from the majority of the flames and was able to make his way down the ladder to assist with extricating the injured firefighters.
Truck 16’s crew quickly set up its 100-foot aerial and removed O’Barsky from the ledge. A ground ladder was also raised to the level of the catwalk on the opposite side. O’Barsky sustained a first-degree burn to his upper chest; Bridges suffered second-degree burns to his wrist. Both were transported to PRMC by Medics 16-2 and 1, respectively. With four members now in or headed to the emergency department, Deputy Chief 1 Keenan responded on-scene and called for a second alarm to provide mutual-aid companies for standby duty at the two empty SFD stations. Deputy Chief 2 Gordy assumed the role of duty officer for the duration of the incident and coordinated the response to concurrent emergency calls.
After the firefighters were brought safely down from the catwalk, Assistant Chief Bryan Records, who had arrived on Truck 16, was designated Operations command. He regrouped the crews, set the ladder pipe on Truck 16’s aerial, secured the silo’s access door in the open position, and began to flood the silo using the unmanned deluge nozzle. A relatively small blast of fire ensued; it was brief and dissipated far above the operating firefighters. After several minutes, water could be seen draining from the hopper beneath the silo. A handline stream was also directed from the ground through the access door to wet any product that adhered to the interior walls of the silo above the door level.
As the contents were being soaked, crews were sent into the plant proper to check for extension. They dismantled the intake pipe but found no evidence of fire spread beyond the silo. Once the sawdust was sufficiently wet, the hopper was opened to remove the burned contents and the ladder pipe was shut down. The incident was declared under control at 1103 hours; on-scene operations were completed by 1246 hours.
Chief See, having responded to the scene, provided a statement to the press regarding the firefighters’ injuries, the then-unknown cause of the fire, and the fact that no plant personnel were known to have been injured. At a press conference later that afternoon, the names of the injured and their conditions were provided. All three suffered relatively minor burns, but the presence of facial burns on Lt. Rathel and concern that airway compromise could ensue resulted in his transfer to the regional burn unit at Baltimore’s Johns Hopkins Bayview Medical Center for observation. He was transported by the Maryland State Police medevac helicopter. Family members were driven to the hospital in an SFD vehicle. He was released the next day.
CISD
With so many fellow firefighters stricken, SFD administration, recognizing the potential for critical incident stress to manifest, arranged for an immediate critical incident stress debriefing (CISD) with an on-call counselor the afternoon of the incident. The SFD personnel involved in the fire attack and rescues were taken out of service for this session. Neighboring volunteer fire departments of Hebron, Parsonsburg, and Fruitland, Maryland, provided fire and EMS mutual-aid coverage for SFD units during the fire and the debriefing. O’Barsky and Bridges had been released from the hospital and were able to attend the session, which provided probably the best therapy of all for worried attendees.
The fire was investigated by Maryland state fire marshals, three of whom arrived within a half hour of fire crews. Although the fire’s origin has not yet been definitively determined, it is theorized that the fiery blasts that injured firefighters were likely dust explosions resulting from the hose stream’s stirring up the heated sawdust, increasing the surface area available for combustion, and leading to rapid conflagration. The ladder pipe caused the same reaction, but its continued cooling stream eventually reversed the combustion reaction.
LESSONS LEARNED/REINFORCED
A formal critique of the handling of the incident will be held.
• Although its fire district is surrounded by farmland, Salisbury firefighters have had little experience with silo fires and thus did not fully appreciate the danger of dust explosions.
• Moreover, the second crew made the same mistake as the first one because members were unable to confer with the first crew about what had occurred. The need to obtain complete situation reports after any unusual event was a valuable lesson. Reinforced, too, was the importance of using full personal protective gear and SCBA-they provided almost complete protection to the two firefighters engulfed by the fireball.
Every firefighter in the SFD knows that they, too, could have made the same decision and could have been in the same position and suffered the same consequences. Fortunately, because of the lessons learned from this incident, this will not happen. ■
SAWDUST STORAGE FIRES
Fires in sawdust storage containers, often complicated by explosions, occur with surprising frequency. An Internet search uncovered significant incidents in Sacramento, California; Archbold, Ohio; Pella, Iowa; Sagola, Michigan; Lafayette, Pennsylvania; Roseville, Minnesota; Grove Hill, Alabama; Chilliwack, British Columbia; Cornwall County, UK; and Longview, Washington, to list but a few.
Sawdust collection systems exist in virtually every town in the modern world. Industrial-sized sawdust silos may be found at any manufacturing facility that machines wood or stores sawdust as fuel for energy-producing furnaces. Smaller, but no less dangerous, containers can be found at woodworking shops at businesses, schools, and homes. If you have not considered the potential for such an incident previously, consider this: It has been calculated that wood dust can produce twice the overpressure-i.e., twice the explosive force-as propane gas.
Some of these incidents have been as significant as the Salisbury, Maryland, fire and explosion, but with even more serious consequences. For example, on December 21, 1997, three firefighters in Iredell County, North Carolina, were injured when an agricultural silo containing sawdust exploded approximately 2½ hours into the extinguishing efforts. The blast occurred when the lower access panels were removed for overhaul after the contents were thought to be extinguished and the explosion’s force blew the top off the container and the firefighters who were standing around it. They were wearing class III harnesses, but the catwalk to which they were anchored was blown apart. A United States Fire Administration (USFA) investigation report is available at http://ncsp.tamu.edu/reports/USFA/silo.pdf.
On October 1, 2003, in New Knoxville, Ohio, two volunteers were killed and eight others injured when a 75-foot-tall concrete silo containing sawdust exploded as water streams were directed from above. Below, piercing nozzles were operated, and product was removed. One fatality was a firefighter on an aerial device who was directing the stream. This explosion, like that in North Carolina, occurred well after firefighting efforts had been initiated. A report on the in-depth National Institute of Occupational Safety and Health (NIOSH) investigation of this incident is available at http://www.cdc.gov/niosh/fire/reports/face200332.html.
Incident reports repeatedly show that such fires can result in dust explosions whenever the product is agitated. On May 4, 2002, Sacramento, California, firefighters were just arriving at a woodworking plant when a blast occurred in its three-story-tall sawdust hopper, throwing a worker from an eight-foot-high catwalk to the ground. Automatic sprinklers already had controlled the fire when a worker “dumped” the smoldering contents, shaking up the contents and allowing oxygen to enter. In another incident in Ohio, firefighters were burned when they opened an overhead duct containing burning sawdust; the spilling of the contents resulted in a large fireball.
There is no universally safe approach to handling these types of fires partly because of the variety of containers in which sawdust can be stored. For instance, many times the product is kept in converted agricultural silos, which can be oxygen-limiting or conventional, with different approaches required by each. The former is handled by sealing off the silo, protecting the exposures, and letting the fire burn itself out, often over a period of days. The introduction of an inert gas, such as carbon dioxide or nitrogen, has been both suggested and condemned. Conventional silos, which are not airtight, present the same environment as the collection tower found at the Maxum plant but are often much larger.
Some general recommendations include the following:
• The material on fire is rendered virtually useless by the fire and extinguishing efforts, and those responsible for the risk/benefit analysis must take this into account when contemplating fire mitigation approaches. In other words, at a sawdust container fire, there is nothing in danger that is worth risking even a firefighter injury.
• Preplanning should include requiring explosionproof construction-i.e., panels and doors that will open easily if overpressurization occurs and the installation of dry sprinkler connections for fire department use in a fire.
• If there is no prepiped waterway to the container interior, use only unmanned aerial devices to apply water so as not to endanger personnel.
• Apply water gently; avoid straight and forceful streams, to prevent agitation of contents.
• Exercise extreme caution in opening access doors or unloading hoppers when a fire is involved. Personnel and apparatus should first be moved to a safe distance. Where doors must be opened, the door handle should be hooked from a distance, using a pike pole or a rope.
The ubiquity of such hazards, coupled with the fire service’s general lack of awareness of their potential dangers, can create a deadly combination. Firefighters must approach these fires as if a container of flammable gas were involved; the effects of agitating sawdust by hose streams or by removal would be identical.
■MARK COTTER, a member of the fire service for more than 30 years, is a volunteer firefighter/EMT-B with the Salisbury (MD) Fire Department and is employed as an emergency department physician’s assistant. Previously, he served with departments in New Jersey and Pennsylvania as an EMT-paramedic, an emergency services consultant, and fire chief. Cotter is author of the column “From the Jumpseat” in the Fire Engineering E-Newsletter.
