Captain Killed and Six Firefighters Injured at a Propane 

Explosion in an Office Building–Maine 

Page i

F2019-16 • January 3, 2022

Executive Summary On September 16, 2019, a 68-year-old 

captain was killed in a propane 

explosion and six firefighters were 

injured. At approximately 0808 hours, 

the fire and rescue department was 

dispatched to an office building for a 

possible propane leak. The building 

maintenance supervisor had called the 

fire station directly. The fire chief 

called county dispatch, so the call 

could be transmitted by radio to the 

fire and rescue department. County 

dispatch alerted Car 1, Engine 2, and 

Tower 3 at 0808 hours. The fire chief 

(Car 1) arrived on-scene and met with 

the building maintenance supervisor. 

The employees had moved to their

designated evacuation area, which 

was the northwest corner of the 

parking lot. Firefighters from Engine 

2 and Tower 3 arrived on-scene. The officer and firefighter from Tower 3 initiated air sampling with a 

portable multi-gas detector. Tower 3 members conducted air sampling around the propane tank. They 

found no indication of a propane leak, but the propane tank was empty with frost on the bottom half of 

the tank and the ground around the tank at approximately 0813 hours. Firefighters were ordered to the 

basement of the building by the fire chief. The fire chief and a captain who responded on Engine 2 

were reportedly on the 1st floor of the building. A firefighter assigned to Tower 3 went to the basement 

with a portable multi-gas detector. The captain from Tower 3 was already in the basement with the 

building maintenance supervisor and a firefighter from Engine 2. The firefighter from Tower 3 stated 

that the multi-gas detector started to read a lower explosive limit (LEL) as he went down the basement 

stairs. The LEL continued to increase until the multi-gas detector alarmed at 100% at the bottom of the 

steps. The firefighter from Tower 3 stated he was in the basement less than one minute. At 0817 hours, 

Destruction of the propane explosion. This photo shows 

Side Alpha/Side Delta of the building. The white debris 

is insulation and papers from the building.

(Photo courtesy of the Fire and Rescue Department)
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Captain Killed and Six Firefighters Injured at a Propane Explosion in an 

Office Building–Maine

Report # F2019-16 

an explosion occurred that leveled the building. The captain of Engine 2, who was reportedly on the 1st

floor, was killed as a result of injuries sustained in the explosion. Two firefighters were standing on 

Side Bravo in the parking lot when the explosion occurred. The force of the explosion threw them to 

the dirt road approximately 20 – 30 feet away. Six firefighters, including the fire chief, and the 

building maintenance supervisor were injured. Initially, all six injured firefighters were transported to a 

local hospital. One firefighter was treated and released. The other five firefighters were transported by 

air or ground to various hospitals throughout the state. The captain of Engine 2 was pronounced 

deceased by EMS personnel at approximately 0840 hours. 

Contributing Factors • Lack of locating and marking of underground utilities prior to digging or excavation

• Installation of vertical protective posts (Bollards) that severed the propane supply line 

• Lack of pressure testing an empty tank by the propane company 

• Odorant fade or scrubbing of ethyl mercaptan by soil and concrete

• Lack of scene size-up and risk assessment

• Lack of incident management 

• Lack of understanding a multi-gas monitor’s capability 

• Improper gas sampling, monitoring, and detection 

• Lack of hazardous materials training and recertification.

Key Recommendations • Fire departments responding to a hazardous materials incident should ensure that a scene sizeup and initial risk assessment are performed. In addition, fire departments should establish 

isolation zones and ensure a continuous risk assessment is conducted throughout the incident 

• Fire departments should ensure incident commanders initiate a defensive strategy and 

communicates the incident action plan (tactics) during initial operations of a hazardous 

materials incident. The strategy and incident action plan are revised based upon the tactical 

objectives taken to mitigate the hazard 

• Fire departments should ensure firefighters are trained to understand the scrubbing or odorant 

fade of ethyl mercaptan from propane. This training includes the use of multi-gas detectors to 

determine if a potentially explosive atmosphere is present. 

The National Institute for Occupational Safety and Health (NIOSH) initiated the Fire Fighter Fatality Investigation and Prevention Program to examine 

deaths of fire fighters in the line of duty so that fire departments, fire fighters, fire service organizations, safety experts and researchers could learn from these 

incidents. The primary goal of these investigations is for NIOSH to make recommendations to prevent similar occurrences. These NIOSH investigations 

are intended to reduce or prevent future fire fighter deaths and are completely separate from the rulemaking, enforcement, and inspection activities of any 

other federal or state agency. Under its program, NIOSH investigators interview persons with knowledge of the incident and review available records to 

develop a description of the conditions and circumstances leading to the deaths in order to provide a context for the agency’s recommendations. The NIOSH 

summary of these conditions and circumstances in its report is not intended as a legal statement of facts. This summary, as well as the conclusions and 

recommendations made by NIOSH, should not be used for the purpose of litigation or the adjudication of any claim.

For further information, visit the program website at www.cdc.gov/niosh/fire or call toll free 1-800-CDC-INFO (1-800-232-4636).
Page 1 

F2019-16 • November 18, 2020

Introduction On September 16, 2019, a 68-year-old captain was killed, and six firefighters were injured in a propane 

explosion at an office building. On October 17, 2019, an investigator and two occupational health and 

safety specialists with the National Institute for Occupational Safety and Health (NIOSH) Fire Fighter 

Fatality Investigation and Prevention Program traveled to Maine to investigate the circumstances 

contributing to this incident. The NIOSH representatives met with fire and rescue department officials 

including the fire chief, the deputy chief of operations, and members of the department involved in this 

incident. NIOSH investigators also met with a representative for the town’s code enforcement and 

planning office; officers from the town’s police department; employees from the town’s public works 

division; employees of the private ambulance service; representatives from the Maine Fuel Board, 

Maine Department of Labor, Bureau of Labor and Standards, Workplace Safety and Health Division; a 

representative from the federal Occupational Safety and Health Association (OSHA); representatives 

from the Maine Office of the State Fire Marshal, Investigation Division; representatives from the 

Maine Office of the State Medical Examiner; representatives from the Maine Fire Service Institute; 

and representatives from the county’s 9-1-1 Communications Center. NIOSH investigators visited the 

incident site with representatives of the Maine Office of the State Fire Marshal. NIOSH investigators 

conducted interviews with the fire and rescue department officers and firefighters, plus members of 

mutual aid fire departments directly involved in this incident. The NIOSH investigators inspected and 

photographed the personal protective clothing of the deceased firefighter and injured firefighters. 

NIOSH investigators reviewed training records and standard operating procedures (SOPs) from the 

involved fire and rescue department. Photographs and building information were obtained from the 

Maine Office of the State Fire Marshal, Investigation Division. 

Fire and Rescue Department The fire and rescue department delivers fire protection and life safety services to an area encompassing 

56 square miles and a population of 8,200. A college located in the town adds an additional population 

of approximately 1,800 students during the school year. The department operates out of two fire 

stations. The department’s apparatus consists of two pumpers (Engine 1 & Engine 2), one tower ladder

(Tower 3), one squad truck (Squad 1), one rescue/air truck (Rescue 1), one communications vehicle 

(Com1), one Chief’s vehicle (Car 1), a hazmat trailer, and a Gator which is used as a quick attack on 

wood/brush fires and in the winter as a rescue unit with tracks. There are 12 -15 active members of the 

fire and rescue department, which responds to approximately 400 alarms annually. 

The rank structure for the fire and rescue department is:

• Fire Chief 

• Deputy Chief 
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Captain Killed and Six Firefighters Injured at a Propane Explosion in an 

Office Building–Maine

Report # F2019-16

• Captain

• Lieutenant

• Firefighter 

The fire and rescue department members are emergency medical technicians who respond to EMS 

incidents supporting the private hospital-based ambulance service. 

The fire chief is a paid member of the department. The department has four full-time members that 

work Monday – Friday from 0700 – 1900 hours. Two members work daily for two days on and then 

have two days off. Also, the department has a per diem shift from 0800 – 1630 hours Monday through 

Friday. Note: On September 16, the full-time work schedule was changed due to the town’s annual fair 

which started on this date and continued through September 23. The work scheduled was changed 

Monday – Friday from 0700 – 1900 hours to 1000 – 2200 hours. The per diem shift was changed from 

0800 – 1630 hours to 1000 – 1830 hours 

The fire and rescue department has written policies and SOPs, which are available to all department 

members. 

Training and Experience Fire service training in Maine is provided by the Maine Fire Service Institute (MFSI). The MFSI is a 

division within Southern Maine Community College. They had a full-time staff of 10 and an additional 

100 instructors throughout the state of Maine at the time of the incident. MFSI produces a variety of 

programs in regions around the state of Maine to meet the demands of the local fire departments. 

Complementing the program delivery, MFSI also serves as the certification entity for all firefighter 

programs. MFSI accomplishes all this by fostering partnerships and collaborating with local 

departments, regional programs, the Fire Science Programs of Southern Maine Community College 

and Eastern Maine Community College and other state agencies, such as the Maine Office of the State 

Fire Marshal and the Maine Bureau of Labor and Standards. 

MFSI offers National Fire Protection Association (NFPA) training including NFPA 1001, Standard for 

Fire Fighter Professional Qualifications, Fire Fighter I which is approximately 150 hours and Fire 

Fighter II which is approximately 150 hours. MFSI also offers a 75-hour course which is the minimum 

requirement mandated for any firefighter that performs interior structural firefighting by the Maine 

Department of Labor (See Section on Maine Bureau of Labor and Standards). 

MFSI also offers the following Pro Board accredited certification training: 

• NFPA 1001, Standard for Fire Fighter Professional Qualifications, Fire Fighter I and Fire 

Fighter II

• NFPA 1021, Standard for Fire Officer Professional Qualifications, Fire Officer I and Fire 

Officer II

• NFPA 1041, Standard for Fire and Emergency Services Instructor Professional Qualifications, 

Instructor I and Instructor II
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Captain Killed and Six Firefighters Injured at a Propane Explosion in an 

Office Building–Maine

Report # F2019-16

• NFPA 1035, Standard on Fire and Life Safety Educator, Public Information Officer, Youth 

Firesetter Intervention Specialist and Youth Firesetter Program Manager Professional 

Qualifications, Fire Life Safety Educator I. 

Note: The Pro Board is a non-profit corporation that was incorporated in 1990 as the “National 

Board on Fire Service Professional Qualifications.” The organization is commonly known as the Pro

Board.

Fire Inspector certifications are through the NFPA.

Hazardous materials training and certification is provided through the Maine Emergency Management 

Agency, State Emergency Response Commission (SERC). The SERC supports training of first 

responders and emergency managers across the state. Training is coordinated regionally through the 

16-county local emergency planning committees. The SERC offers the following hazardous materials 

training, which complies with OSHA 29 CFR 1910.120, Hazardous Waste Operations and Emergency 

Response: 

• First Responder Awareness Level

• Hazardous Materials Operations Level

• Hazardous Materials Technician Level [OSHA 1990] 

The deputy chief of the fire and rescue department who served as incident commander of the incident 

had the following certifications: NFPA 1001, Standard for Fire Fighter Professional Qualifications, 

Fire Fighter I and Fire Fighter II. The deceased captain had the following certifications: NFPA 1001, 

Standard for Fire Fighter Professional Qualifications, Fire Fighter I and Fire Fighter II. The fire chief 

had the following certifications: NFPA 1001, Standard for Fire Fighter Professional Qualifications, 

Fire Fighter I and Fire Fighter II. 

Maine Bureau of Labor and Standards

The Maine Department of Labor, Bureau of Labor and Standards mandates that all firefighters be 

certified to meet the Interior Structural Firefighter - Minimum Training Requirements. This 75-hour 

course consists of 18 topics. 

• The History and Orientation of the Fire Service 

• Firefighter Qualifications and Safety

• Fire Service Communications

• Incident Management System 

• Fire Behavior

• Portable Fire Extinguishers 

• Firefighter Tools and Equipment 

• Response and Size-Up

• Forcible Entry 

• Ladders 

• Search and Rescue 

• Ventilation

• Water Supply 

• Fire Hose, Nozzles, Streams, and Foam 
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Report # F2019-16

• Firefighter Survival 

• Salvage and Overhaul 

• Firefighter Rehabilitation

• Fire Suppression 

The curriculum is based on training requirements from the Maine Department of Labor, Bureau of 

Labor and Standards and NFPA 1001, Standard for Fire Fighter Professional Qualifications. 

Based upon Maine state statutes, the following apply to each fire department in the state: 

• Maine MRSA (Maine Revised Statutes Annotated) Title 26 

§2102. Firefighter Training and Education 

• Maine MRSA Title 26

§2103. Standards for Equipment and Clothing 

• Maine MRSA Title 26 

§2104. Required Provision and Use of Protective Equipment 

Apparatus, Staffing, and Communications On September 16, 2019, at 0808 hours, the fire and rescue department was dispatched to a report of a 

possible propane leak at an office building. The following resources were dispatched at 0808 hours: 

• Car 1 (Fire Chief) (PAR 1)

• Engine 2 (PAR 3) 

• Tower 3 (PAR 3) 

The 9-1-1 center and communication center (identified as county dispatch) is operated by the county. 

County dispatch was managed by an interim director at the time of this investigation and staffed with 

11 dispatchers. County dispatch receives approximately 1100 calls annually. Dispatchers work tours of 

0600 hours to 1800 hours and 1800 hours to 0600 hours. The minimum staffing is two dispatchers per 

shift. All dispatchers are assigned permanent day or night tours and work three days the first week and 

four days the second week. 

The county 9-1-1 center and communication center dispatches for 17 fire departments, four municipal 

police departments, the county Sheriff’s Office, and the private EMS agency. The county dispatch 

transmits on a VHF frequency. The county is divided into County Fire North and County Fire South 

dispatch frequencies. The state fire channel is used for a tactical channel for working incidents. 

Building Construction

The structure involved in the incident served as a central office for an organization that provides 

residential and life skill support to individuals with intellectual and developmental disabilities since 

2003. The original building was one story with a partial basement and was approximately 2500 - 3000 

square feet (See Photo 1). 
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Captain Killed and Six Firefighters Injured at a Propane Explosion in an 

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Report # F2019-16

The organization identified the need for a larger facility due to training, meeting rooms, and 

administrative purposes. They purchased land to the east of the original structure for their expansion 

project. In the fall of 2018, the organization started construction of the expansion project (See 

Diagram 1) which included an addition and parking on all sides of the building. 

The addition included a basement for utilities and storage; a 1st floor with a large meeting room, 

offices, kitchen, and restrooms that adjoined the existing 1st floor offices; and a 2nd floor with offices 

and restrooms. The new basement did not connect with the existing basement in the original building. 

The basement had two rooms that were separated by a block wall (See Diagrams 2, 3 and 4).

During the renovation project, the existing propane tank (250 gallons), which was located on the Side 

Bravo/Side Alpha corner of the original building was removed. A new propane tank (500 gallons) was 

located on the southeast corner of the property approximately 100 feet from the Side Bravo/Side 

Charlie corner of the new addition. The propane tank was protected by a jersey barrier. 

Photo 1. The original structure that was purchased in 2003 and before the renovation 

project in 2018. 

(Photo adapted from Google Earth) 
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Captain Killed and Six Firefighters Injured at a Propane Explosion in an 

Office Building–Maine

Report # F2019-16

Diagram 1. Diagram shows the changes that were made to the structure during the 

renovation project. 

(Diagram courtesy of the Maine Office of the State Fire Marshal) 
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Captain Killed and Six Firefighters Injured at a Propane Explosion in an 

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Report # F2019-16

Diagram 2. Blue highlights the new basement as part of the renovation project. 

The green highlight is the existing basement with offices.

(Diagram courtesy of the Maine Office of the State Fire Marshal) 
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Captain Killed and Six Firefighters Injured at a Propane Explosion in an 

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Report # F2019-16

 Diagram 3. The floor plan of the 1st floor of the new and existing building. 

(Diagram courtesy of the Maine Office of the State Fire Marshal) 
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Captain Killed and Six Firefighters Injured at a Propane Explosion in an 

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Report # F2019-16

Diagram 4. The floor plan of the 2nd floor of the new building, which consisted 

primarily of offices. 

(Diagram courtesy of the Maine Office of the State Fire Marshal)
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Captain Killed and Six Firefighters Injured at a Propane Explosion in an 

Office Building–Maine

Report # F2019-16

The construction was completed, and the building was operational on July 1, 2019. The two-story 

office building with a full basement building was approximately 32 feet wide by 81 feet long. The 

building consisted of approximately 8,300 square feet.

Timeline of Construction and Renovation Project

The construction events that were relevant to this incident were:

• October 29, 2018: Building contractor broke ground for construction of the new 

structure. 

• June 20, 2019: Propane tank was placed on the building office property, ditching 

was completed for the propane supply line, and propane service 

company delivered 125 gallons of propane. 

• June 28, July 1- 2, 2019: Parking lot paved. The “service riser” or “anodeless riser” 

for the propane system was paved over by the paving company. 

• July 1, 2019: Construction project completed. Employees started moving 

furniture and office equipment into the building. 

• July 25, 2019: Propane company delivered 257.3 gallons of propane. 

• August 1, 2019: Company continued the moving process into the new building 

• September 1, 2019: Building opened for business. Note: The Third-Party Inspector 

 never certified the completion of the construction project.

• September 10, 2019: Four bollards were drilled into the ground on Side Bravo in the 

vicinity of the propane supply line entering the building. One of 

the bollards severed the propane supply running from the tank to 

the building. The bollards were installed to protect the three air 

conditioning units on Side Bravo of the building (See Photo 2). 

Note: The company that installed the bollards never requested 

Maine “Dig-Safe” to mark underground utilities. 

• September 12, 2019: Employees reported no hot water in the building. The hot water 

was supplied by the propane boiler. 

• September 13, 2019: Propane company notified by the building maintenance 

supervisor that the propane tank was empty. The propane 

company delivered 391.9 gallons. 

• September 16, 2019: Propane tank was discovered empty with frost on the bottom half 

of the tank and the ground around the tank at approximately 0805 

hours. The building exploded at approximately 0817 hours. 

Third Party Inspection Program

The Third-Party Inspection Program in Maine began in July 2011 and primarily takes the place of the 

municipal building inspector for towns that are required to enforce the Maine Uniform Building and 

Energy Code but have elected not to conduct inspections. In these towns, the applicant is responsible 

for hiring a building inspector to review their plans prior to commencing construction and to then 

conduct the necessary building inspections after construction is completed. The scope of the third-party 

inspector does not include the inspection of heating, air conditioning, and ventilation (HVAC); 

plumbing; and electrical, except for some items that may have requirements within the Maine Uniform 

Building and Energy Code, such as insulating hot water supply lines within the plumbing system 
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[MUBEC 2015]. These components are the responsibility of state and local inspectors and/or licensed 

tradesmen. After completion of the project, the inspector provides a report to the town certifying that 

the project satisfies all relevant code requirements and requests the town issue a certificate of 

occupancy.

The Third-Party Inspection Program uses the International Codes Council (I-Codes), which are 

international codes developed by the International Code Council (ICC). The ICC is a family of fifteen 

coordinated, modern building safety codes that help ensure the engineering of safe, sustainable, 

affordable, and resilient structures.

The Third-Party Inspection Program consists of a third-party inspector reviewing and approving the 

following steps during a construction project: 

• Construction plans and documents 

• Footing forms with reinforcement installed prior to concrete placement 

• Footings with concrete installed

Photo 2. The bollards (red circles) that were placed to protect the air conditioning units 

in the parking lot on Side Bravo of the office building. When the bollards were driven 

into the ground, one of the bollards severed the propane supply line.

(Photo courtesy of the Maine Office of the State Fire Marshal)
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Captain Killed and Six Firefighters Injured at a Propane Explosion in an 

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• Foundation forms with reinforcement installed prior to concrete placement 

• Foundation with concrete installed 

• Basement prior to concrete (checking drainage and vapor barrier), which often occurs at the 

same time as footings with concrete installed

• Framing of structure prior to covering (this is typically done several times as construction 

progresses) 

• Installation of exterior vapor barrier and wall and roof coverings 

• Fire caulking and sealing 

• Insulation prior to covering 

• Installation of interior finishes 

• Final inspection (includes finished building and all fire safety components such as fire alarm 

and sprinkler systems). 

The building’s maintenance supervisor contacted and hired a licensed third-party inspector for the 

renovation of this office building. The third-party inspector never received all the certified construction 

plans and never issued a notice to proceed for this project. A certificate of occupancy was never issued 

to this business by the town. 

Timeline 

The following timeline is a summary of events that occurred as the incident evolved. Not all incident 

events are included in this timeline. The times are approximate and were obtained by studying the 

dispatch records, audio recordings, witness statements, and other available information. This timeline 

also lists the changing fire behavior indicators and conditions reported, as well as fire department 

response and fireground operations. The timeline is not intended, nor should it be used, as a formal 

record of events.

Dispatch Communications & Fire 

Department Response

Time Fireground Communications & 

Fireground Operations

September 16, 2019 

The maintenance supervisor from the 

office building called the fire chief at 

the fire station and advised there was a 

possible propane leak in the building. 

0806 

Hours 
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Captain Killed and Six Firefighters Injured at a Propane Explosion in an 

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Dispatch Communications & Fire 

Department Response

Time Fireground Communications & 

Fireground Operations

Car 1 (Fire Chief) called county 

dispatch requesting the fire and rescue 

department be dispatched to the office 

building for a possible propane leak in 

an office building. FD Incident 2019-

275.

0807 

Hours

County dispatch dispatched the fire

and rescue department to the office 

building for a possible propane leak. 

Car 1, Tower 3, and Engine 2 were 

dispatched. 

08:08:47

Hours

Car 1 responded to the office building. 08:08:51 

Hours

Car 1 on-scene at the office building. 0810 

Hours

Car 1 met with the building 

maintenance supervisor.

Tower 3 responded to the office 

building. 

08:11:38 

Hours 

Tower 3 arrived on-scene. 0812 

Hours

Car 1 requested a technician from a 

local propane company respond to the 

office building. 

0813 

Hours

Car 1, the officer, and firefighter from 

Tower 3 were investigating inside and 

outside the structure to locate the 

source of the propane leak. 

Engine 2 responded to the office 

building. 

08:13:51 

Hours

Engine 2 arrived on-scene. 08:14:43 

Hours

The officer (captain) and chauffeur of 

Engine 2 joined the crew of Tower 3 

and Car 1 inside the building. 
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Captain Killed and Six Firefighters Injured at a Propane Explosion in an 

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Dispatch Communications & Fire 

Department Response

Time Fireground Communications & 

Fireground Operations

0816 

Hours

The chauffeur of Tower 3 and a deputy 

chief (jumpseat of Engine 2) were

located on Side Bravo at the edge of 

the parking lot. 

0817 

Hours

An explosion occurred that destroyed 

the office building. 

A town police department sergeant 

(PD3) radioed a Mayday on the police 

department frequency to the county 

dispatch. 

PD3 arrived on-scene and informally 

assumed Command. 

Fire and rescue department’s deputy 

chief (Car 3) responded. 

0818 

Hours

Fire and rescue department’s Squad 1 

(PAR 3) responded to the building 

explosion. 

0820 

Hours

With the original firefighters 

incapacitated, PD3 informally assumed 

command and ordered a 13⁄4-inch 

hoseline into operation to knock down 

the active fire in the building debris. 

Also, PD3 assigned arriving resources 

to locate and treat patients.

The county dispatch dispatched an 

EMS Mass Casualty Incident response 

of five medic units to the incident - 

Medic 33, Medic 31, Medic 41, Medic 

32, and Medic 72. 

Medic 33 responded from the county 

fairgrounds. 

Fire and rescue department’s Engine 1 

(PAR 2) responded to the office 

building. 

0821 

Hours
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Dispatch Communications & Fire 

Department Response

Time Fireground Communications & 

Fireground Operations

Squad 1 arrived on-scene. 0822 

Hours

Medic 33 arrived on-scene. 

Engine 1 arrived on-scene and parked 

behind Engine 2. 

0823 

Hours

Triage on the firefighters inside and 

outside the building was started by 

civilians. 

Fire was showing from the building 

debris created by the explosion on the 

Side Alpha/Side Delta corner of the 

building. 

PD3 requested investigators from the 

Maine Office of the State Fire Marshal

respond. 

0824 

Hours

The EMS Director, who responded on 

Medic 33, assumed Medical Group 

Supervisor. 

A paramedic on Medic 33 assumed 

Triage, Treatment, and Transportation 

Unit Leader, which was located at the 

Side Alpha/Side Bravo corner of the 

parking lot near the highway. 

0827 

Hours

PD3 drove Engine 1, laying a 4-inch 

supply line from a hydrant on the state 

highway to Engine 2. 

Medic 34 and Medic 51 were 

dispatched and responded to the 

building explosion. 

0828 

Hours

 

Car 3 (PAR 1) arrived on-scene. 

Car 3 formally assumed Command. 

0829 

Hours

PD3 met with the Car 3 and provided 

an update. 

The EMS Supervisor pronounced the 

captain of Engine 2 deceased. 
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Dispatch Communications & Fire 

Department Response

Time Fireground Communications & 

Fireground Operations

Medic 31 arrived on-scene. 0830 

Hours

Civilians, EMS personnel, firefighters, 

and law enforcement officers were 

trying to locate and account for all 

injured firefighters and building 

occupants. 

The injured firefighters and building 

occupants were moved to the triage 

area near the highway on the Side 

Alpha/Side Bravo corner of the 

property. 

Medic 31 was enroute to the hospital 

with the captain and firefighter from 

Tower 3. 

0834 

Hours

Crews were still trying to locate and 

account for the deputy chief that 

responded on Engine 2. 

Medic 34 arrived on-scene. 0840 

Hours

Medic 51 and Medic 32 arrived onscene. 0846 

Hours

Medic 34 was enroute to the hospital 

with the fire chief.

Medic 51 was enroute to the hospital 

with the maintenance supervisor. 

0850 

Hours

Medic 32 was enroute to the hospital 

with the chauffeur of Engine 2. 

0852 

Hour 

Medic 41 was enroute to the hospital 

with chauffeur of Tower 3. 

Medic 31 responded back and arrived 

on-scene.

The first investigator from the Maine 

Office of the State Fire Marshal 

arrived on-scene.

0855 

Hours
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Captain Killed and Six Firefighters Injured at a Propane Explosion in an 

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Dispatch Communications & Fire 

Department Response

Time Fireground Communications & 

Fireground Operations

Medic 31 was enroute to the hospital 

with the deputy chief (Engine 2). 

0858 

Hours

Command advised county dispatch 

that the fire in the building was out. 

1000 

Hours

 

1145 

Hours

Investigators from the Maine Office of 

the State Fire Marshal and Office of 

State Medical Examiner started the 

recovery process of the captain of 

Engine 2. 

1225 

Hours

The captain of Engine 2 was removed 

from the building and transported to the 

Office of State Medical Examiner.

Note: When fire investigators secured 

each day of the investigation, law 

enforcement remained on scene for 

scene security. 

September 19, 2019 

Command was dissolved. All 

resources were cleared from FD 

Incident 2019-275. 

1350 

Hours 

Personal Protective Equipment 

The NIOSH investigators evaluated and inspected the personal protective equipment worn by the 

deceased captain of Engine 2 at the police department headquarters evidence room on October 24, 

2019. The captain was wearing his second set of turnout gear that he kept at home. The captain’s 

helmet could not be found. His turnout coat and turnout pants were intact but were not inspected due to 

body fluids. The turnout boots were in good condition. 

The personal protective equipment (turnout gear) was not considered a contributing factor to the 

fatality in this incident. NIOSH investigators conducted no further evaluation or testing of the turnout 

gear. 
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Weather 

At 0753 hours on September 16, 2019, the temperature was 55 degrees Fahrenheit (55o F), the dew 

point was 47 degrees Fahrenheit (47o F), the relative humidity was 74%, and the winds were out of the 

WNW at 6 miles per hour. The conditions were fair. There was a slight trace of precipitation in the 

previous 24 hours [Weather Underground 2019].

Investigation 

On September 16, 2019, at approximately 0750 hours, a maintenance employee for the company 

arrived at the office building. He started moving folding tables from the 1st floor of the building to the 

basement, which was in the new addition of the building. After several trips to the basement, he started 

to feel lightheaded, which he mentioned to the building’s maintenance supervisor. The maintenance 

employee wasn’t sure what caused him to feel lightheaded. Both employees were in the basement at 

this time, which was approximately 0805 hours. The maintenance supervisor advised he was going to 

evacuate all employees from the building. The lights were on in the basement, but the maintenance 

supervisor turned the lights off when he left. There were no offices in the basement, only utilities in 

this new section of the building. There was one office in the basement of the old section of the 

building, but it had a separate entrance. 

Upon exiting the building, the maintenance employee looked at the propane tank, which was located 

on the Side Bravo/Side Charlie corner of the property. The maintenance employee stated there was

frost on the bottom of the tank and on the ground. At approximately 0806 hours, the maintenance 

supervisor called the fire chief (Car 1) requesting the fire and rescue department respond to the facility 

due to a possible propane leak in the building. Approximately 12 employees were evacuated from the 

building and told to locate to the end of the parking lot on Side Delta. At approximately 0807 hours, 

Car 1 called county dispatch requesting the fire and rescue department be dispatched to the office 

building for a possible propane leak. At 0808 hours, county dispatch alerted the town’s fire and rescue 

department for a potential propane leak in an office building. The fire chief responded from fire 

headquarters at 0809 hours and arrived on-scene at 0811 hours. The fire chief parked in the parking lot 

near the highway entrance to the building. Tower 3 (PAR 3) was dispatched at 0811 hours and arrived 

at 0812 hours. Tower 3 pulled in the parking lot past the fire chief’s vehicle facing Side Alpha of the 

structure. The maintenance employee met Car 1 in the parking lot on Side Alpha and walked him to 

Side Charlie to meet with the maintenance supervisor. When Tower 3 arrived, Car 1 advised the crew 

to bring the multi-gas detectors to Side Charlie of the structure. At 0813 hours, Car 1 called county 

dispatch requesting the response of a service technician from the local propane dealer to this incident. 

The captain and firefighter from Tower 3 took the multi-gas detectors to Side Charlie to the propane 

tank. The deputy chief (jumpseat of Engine 2) met the chauffeur from Tower 3. They walked to Side 

Bravo near the end of the parking lot. The captain and chauffeur from Engine 2 went to Side Charlie to 

meet the fire chief and the crew from Tower 3. The firefighter from Tower 3 checked the atmosphere 

on Side Charlie with the multi-gas detector and nothing registered. The firefighter from Tower 3 

noticed frost on the lower half of the propane tank and on the ground around the tank. The firefighter 

checked each bollard with the multi-gas detector, and nothing registered on the multi-gas detector. Car 

1 then directed the crew from Tower 3 to enter the building (See Diagram 5). 
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Diagram 5. The initial response of the fire and rescue department. Firefighters are 

monitoring the area around the propane tank. Engine 2, Tower 3, and Car 1 are on 

Side Charlie. The time was approximately 0815 hours.
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Tower 3 surveyed the 1st floor, and nothing registered on the multi-gas detector. The crew from Tower 

3 then went to the basement. The firefighter on Tower 3 stated the multi-gas detector started alarming 

at 10% LEL at the top of the basement steps. As the firefighter started down the steps, the LEL started 

increasing. Once he reached the basement, the multi-gas detector read 100% LEL and went into full 

alarm. The firefighter from Tower 3 mentioned this to the captain of Tower 3. The captain of Tower 3 

was in the basement and noticed the boiler on the wall. He was near the stairwell and was only in the 

basement approximately 30 seconds before the explosion occurred. 

Prior to the explosion, the captain of Tower 3 was in the basement with the maintenance supervisor, 

the firefighter from Tower 3, and the chauffeur from Engine 2. Car 1 and the captain from Engine 2 

were on the 1st floor of the office building on Side Charlie. The deputy chief (Car 2) (jumpseat of 

Engine 2) and the chauffer of Tower 3 were located on Side Bravo of the building near the end of the 

parking lot. The time was approximately 0816 hours. 

At approximately 0817 hours, an explosion occurred which destroyed the 1st floor and 2nd floor of the 

new addition (See Photo 3). 

The force of the explosion knocked down and seriously injured the captain, two firefighters and the 

maintenance supervisor in the basement. Car 1 and the captain from Engine 2, who were on the 1st

floor, were blown into the basement. The chauffeur of Tower 3 was walking towards Side Alpha of the 

building when the explosion occurred. He was blown into the grass on Side Bravo. The deputy chief 

(Car 2) who was standing on Side Bravo was knocked down. After the explosion, the deputy chief (Car 

2) moved the chauffeur from Tower 3 towards the tire shop and started medical treatment on the 

chauffeur (See Photo 4). 
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Photo 3. Drone footage of the office building and surrounding area after the explosion. 

A mobile home park was located to the south of the building property.

(Photo courtesy of the Maine Office of the State Fire Marshal)
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At approximately 0818 hours, a town police department sergeant (radio designation “PD3”) called 

county dispatch to check on the status of the fire and rescue department due to a possible explosion. He 

left police department headquarters and started driving in the direction of the explosion. He turned onto

the state highway and could see a building had exploded, though he wasn’t sure which one. He arrived 

on-scene and advised the county dispatch that an explosion had occurred at an office building and 

provided the address. PD3 made a request for the power company and ambulances to respond. PD3

informally took command of the incident at this time. The time was approximately 0821 hours. Note:

The actions of PD3 were confirmed by footage from his body camera. Also, at 0821 hours, County 

dispatch transmitted an EMS Mass Casualty Incident response of five medic units to the incident. 

Medic 33, Medic 31, Medic 41, Medic 32, and Medic 72 were dispatched. Medic 33 responded from 

the fairgrounds which was less than a mile away (See Table 1). Engine 1 responded at approximately 

0821 hours with two firefighters.

Photo 4. Location of the firefighters and maintenance supervisor are denoted by the 

red “Xs” after the explosion. 

(Photo courtesy of the Maine Office of the State Fire Marshal)
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When PD3 arrived on scene, he parked his vehicle behind Engine 2 on the state road. Bystanders were 

starting to access the property to assist with injured firefighters and civilians. PD3 went to Side Bravo 

of the building due to power lines down on Side Delta. As he approached the building, he identified the 

entire building had been blown off the foundation. He could see the captain of Tower 3 and the 

firefighter from Tower 3 moving around in the basement of the new addition of the building. 

Bystanders were climbing into the basement of the building on Side Charlie to assist the injured 

firefighters and the facility’s maintenance supervisor. 

There was active fire in the debris pile on top of the original office building. Due to the explosion, all 

fire and rescue department members that responded on the initial alarm were incapacitated. PD3

stretched a 13⁄4-inch hoseline from the bumper of Engine 2. A bystander, who was a volunteer 

firefighter, pumped Engine 2. PD3 passed the hoseline to the captain of Tower 3, who was still in the 

basement. The firefighter from Tower 3 had climbed out of the basement. Squad 1 from the fire and 

rescue department arrived on-scene at approximately 0822 hours. PD3 assigned one firefighter to take 

the hoseline and try and knock down the fire. The two other firefighters were assigned to locate and 

treat the injured firefighters. Engine 1 arrived on the scene at approximately 0823 hours. 

At 0824 hours, Medic 33 arrived on-scene. The agency’s EMS director, who responded on Medic 33, 

assumed the role of medical group supervisor. The paramedic on Medic 33 assumed the role of triage, 

treatment, and transportation unit leader, which was located at the Side Alpha/Side Bravo corner of the 

building’s parking lot near the state highway (See Photo 5). At this time, PD3 called county dispatch 

and requested the response of air ambulances and the state fire marshal’s office. He organized and 

supervised bystanders to get medical supplies and backboards to move the injured firefighters and 

civilian. PD3 also checked on the status of all the office building employees. He assigned a patrol 

officer, who had arrived at the same time of Squad 1, to get the names of the employees. Also, PD3

assigned resources to check the status of the occupants in the trailer park located behind the office 

building. 

PD3 realized that Engine 2 was nearly out of water and went to Engine 1 to lay a 4-inch supply line 

from a hydrant located approximately 400 – 500 feet east of the office building on the state highway. A 

volunteer firefighter pulled the 4-inch supply line off Engine 1 and wrapped the hydrant. PD3 drove 

Engine 1 to the office building parking lot. He disconnected the supply line and hooked the supply line 

into the intake connection on Engine 2. The volunteer firefighter hooked the supply line to the hydrant 

and charged the supply line providing Engine 2 with water. The time was approximately 0827 hours. 
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At 0828 hours, the county dispatch dispatched Medic 34, and Medic 51 to respond to the building 

explosion (See Table 1). Note: Except for Medic 33, all medic units responded from their assigned 

stations, which were in other jurisdictions.

Medic 

Unit

Dispatch Enroute OnSceneEnroute to 

Hospital

At 

Hospital

Back at 

Scene

InService

Medic 33 0821 0821 0823 N/A N/A N/A 1230

Medic 31 0821 0821 0830 0834 0841 0855 1230

Medic 41 0821 0821 0850 0855 0905 N/A N/A

Medic 34 0828 0828 0840 0850 0900 N/A N/A

Medic 51 0828 0828 0846 0850 0900 N/A N/A

Medic 32 0821 0821 0846 0852 0858 0900 1000

Medic 72 0821 0821 0910 N/A N/A N/A 1000

Photo 5. The ambulance is located at the triage, treatment, and transportation unit 

after the explosion. All patients were transported to the hospital from this location. 

(Photo courtesy of the Maine Office of the State Fire Marshal) 

Table 1. The table shows the times for dispatch, enroute, on-scene, enroute to the 

hospital, at the hospital, back at the scene, and in-service.
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The fire and rescue department’s deputy chief (Car 3), who is the county’s emergency manager,

responded from out of town and arrived on-scene at approximately 0829 hours. The deputy chief 

assumed Command which was in the parking lot on the Side Alpha/Side Bravo corner of the building 

near the state highway. The immediate priority of Command was to account for all the firefighters that 

responded to the incident and their condition, plus the employees of the office building. Car 3 assigned 

a fire chief from a neighboring department to be the accountability officer (resource status) to account 

for all first responders on-scene. 

The EMS medical group supervisor (the EMS Director) went into the basement where the captain of 

Engine 2 was located. He pronounced the captain deceased at approximately 0829 hours. Command 

was trying to locate and account for the deputy chief that responded on Engine 2. The deputy chief 

(Car 2) was accounted for at 0834 hours. 

Injured firefighters and the civilian were moved to the triage, treatment, and transportation unit which 

had been established at the corner of the property near the state highway. Medic 31 arrived on-scene at 

0830 hours and then transported the captain from Tower 3 and the firefighter from Tower 3 to the local 

hospital at 0834 hours. Medic 34 arrived on-scene at 0840 hours. Medic 51 and Medic 32 arrived onscene at 0846 hours. The fire chief was transported by Medic 51 and the maintenance supervisor was 

transported by Medic 34 at 0850 hours. At 0852 hours, Medic 32 was enroute to the hospital with the 

chauffeur of Engine 2. At 0854 hours, Medic 41 transported the chauffeur of Tower 3. At 0855 hours, 

Medic 31 returned to the scene. Medic 31 transported the deputy chief (Car 2) from Engine 2 to the 

hospital at 0858 hours. This completed the patient care and transportation component of this incident. 

Command advised county dispatch of this benchmark. Also, Command started to demobilize fire and 

EMS resources that were on-scene. Also, Command advised the county dispatch to cancel all other 

responding resources. The scene was secured awaiting the arrival on investigators from the Maine 

Office of the State Fire Marshal. The first investigator from the Maine Office of the State Fire Marshal

arrived at 0855 hours. Others continued to arrive throughout the morning. 

The fire was completely extinguished and declared out by Command at approximately 1000 hours. The 

state medical examiner and investigator arrived on-scene at approximately 1115 hours. At 1145 hours, 

investigators started the recovery process for the captain from Engine 2. This process was completed 

by 1225 hours and the captain was transported to the Maine Office of the State Medical Examiner in 

Augusta, Maine. 

At 1350 hours on September 19, 2019, Command was dissolved, and all resources were clear from the 

scene. 

Contributing Factors

Occupational injuries and fatalities are often the result of one or more contributing factors or key 

events in a larger sequence of events that ultimately result in the injury or fatality. NIOSH 

investigators identified the following items as key contributing factors in this incident that ultimately 

led to the fatalities:

• Lack of locating and marking of underground utilities prior to digging or excavation
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• Installation of vertical protective posts (Bollards) that severed the propane supply line 

• Lack of pressure testing an empty tank by the propane company 

• Odorant fade or scrubbing of ethyl mercaptan by soil and concrete

• Lack of scene size-up and risk assessment 

• Lack of incident management

• Lack of understanding a multi-gas monitor’s capability

• Improper gas sampling, monitoring, and detection 

• Lack of hazardous materials training and recertification.

Cause of Death

According to the death certificate, the medical examiner listed the victim’s cause of death as due to 

blunt force injuries to the head and torso associated with blast injuries. The manner of death was 

accidental.

Recommendations 

Recommendation #1: Fire departments responding to a hazardous materials incident should ensure 

that a scene size-up and initial risk assessment are performed. In addition, fire departments should 

establish isolation zones and ensure a continuous risk assessment is conducted throughout the 

incident.

 

Discussion: At this incident, fire and rescue members responded to the report of an odor of propane. 

The fire chief arrived on-scene followed by Tower 3 and Engine 2. Five of the seven firefighters went 

immediately to Side Charlie and operated in this area and near the propane tank. Eventually the five 

firefighters entered the building. At this time, the propane leak was not identified. Several firefighters 

noticed the frost on the lower part of the propane tank and ground but did not communicate this 

information to the fire chief. The firefighter from Tower 3 stated the multi-gas detector started 

alarming at 10% LEL at the top of the basement steps. The firefighter stated that the LEL continued to 

increase as he descended down the steps. Once he reached the basement, the multi-gas detector was 

reading 100% and went into full alarm. The firefighter stated at no time did he smell ethyl mercaptan. 

Unlike a fast paced, offensive structural firefighting incident, a hazardous materials incident should 

start out in the defensive strategy. 

The key point to remember is that a hazardous materials response begins with identification. 

Familiarity with hazardous materials recognition and identification processes is an essential skill for all 

responders. For incidents dealing with any hazardous material, including propane and natural gas, the 

size-up process starts with the dispatch center. For any known propane emergency response, the 

dispatch center should attempt to obtain all pertinent information from the person reporting a propane 

leak incident. This information should include (if known): 

• Involved material(s) name, type, and/or class 

• Amount of material involved and the size of tank 

• Problem (leak, spill, fire, etc.) and its location
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• Number of people injured or exposed [Fire and Rescue Departments of Northern Virginia 

2014]. 

The dispatcher should remain on the phone with the caller to gain additional information after entering 

the call for dispatch. Any additional information should be relayed to responding units after dispatch. 

A representative from all agencies that may have a responsibility at the incident need to be contacted 

and asked to meet the fire department personnel at safe location at the scene. If the response call is 

generated by a responsible party with a knowledge of the hazardous situation, the responsible party 

should be instructed to meet the dispatched units at a safe location [Blue Card 2018]. 

First due companies must start the research process while enroute. This process involves using the 

Department of Transportation, Pipeline and Hazardous Materials Safety Administration, Emergency 

Response Guide (ERG) to identify: 

• Material properties

• Safe staging distances

• Evacuation distances 

• Isolation and protective zones distances (hot, warm, and cold zone determinations) [ERG 

2016]. 

Hazardous materials incident sites are classified into hazard zones. The different hazard zones identify 

the competency levels required perform operations in a specific zone. These zones are:

• Hot zone: an immediately dangerous to life and health (IDLH) environment which is 

contaminated with products that require the full use PPE when operating in this zone. 

• Warm zone: a defined area just outside of the hot zone that has the potential to become IDLH 

 contaminated that requires a defined level of use of PPE when operating in this zone. 

• Cold zone: a defined safe area outside of the warm zone that has little or no chance of 

becoming IDLH contaminated where no PPE is required. The cold zone is where the incident 

command, support personnel and uncommitted resources are all located. 

The first arriving company should respond to the scene, upwind/uphill (whenever possible), in a 

defensive manner. All other companies should respond directly to a staging location designated by the 

first due unit or the dispatch center. This area should be upwind and a sufficient distance away from 

the incident to keep the scene clear and maintain good access to the incident site. If a representative 

from the propane company is not on-scene, the incident commander should ask the dispatch center for

their estimated time of arrival [Fire and Rescue Departments of Northern Virginia 2014]. 

The initial radio report should be performed from the front seat of an engine company or the first 

arriving resource. Once the radio report has been given and the dispatch center acknowledges the 

report, the company officer of the first arriving engine or first arriving resource can be out of the 

apparatus and start to conduct a reconnaissance of the incident scene. The size-up report should 

include: 

• Result of a 360-degree size-up (if performed)

• Information on the size, location, and identity of material(s) involved 

• Confirmation of the wind direction 
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• Accountability location

• Any immediate safety concerns.

The wind direction can be retrieved from different areas, but it is very important the wind direction is 

confirmed during the initial size-up. Wind can be redirected by trees, structures, the terrain, or other 

barriers.

Other information should be identified through the size-up/recon process and be reported on the 

follow-up report or subsequent conditions, actions, and needs (CAN) reports. Major reporting items 

include: 

• Involved material(s) identity

• Size and overall amount of the material

• Inside vs. outside 

• Where are the materials stored: building, vehicle, tanker, train, airplane, in a field 

• Hazards of the material to the public 

• Explosion hazards 

• How have the material(s) been dispersed after the trigging event 

• Is the material continuing to be released [Blue Card 2018]. 

The basic level of any hazardous materials operations should meet the requirements of 29 CFR 

1910.120, Hazard Waste Operations and Emergency Response (HAZWOPER) Operations Level and

should follow this standard incident action plan (IAP): 

• Operate in a DEFENSIVE manner

• Provide for the safety of all personnel and the public 

• Evacuate exposed areas if necessary

• Identify and isolate the hot and warm zones

• Deny any entry

• Attempt to identify the products involved 

• Upgrade the assignment based on the incident’s hazard profile 

• Contain the release from a safe distance, and keep it from spreading

• Protect exposures [OSHA 1990]. 

Atmospheres that may have potentially flammable or explosive vapors include but are not limited to: 

a reported natural gas or propane leak, a reported combustible liquid fuel spill, a suspected 

contaminated environment, and confined space which may also be oxygen deficient or enriched. 

To ensure a proper risk evaluation is conducted, incident commanders should perform the following 

actions:

• Conduct an appropriate size-up and determine resource needs. 

• Establish initial isolation zones – initial isolation and protective action distances per the 

Emergency Response Guide recommendations.

• If multiple victims are present or expected, determine the best location to establish a gross 

emergency decontamination corridor and ensure an adequate water supply. Companies laying 

supply lines should maintain situational awareness and not be forced into an untenable position. 
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• All personnel exiting the apparatus shall have personal protective equipment (PPE) in place 

including self-contained breathing apparatus (SCBA); immediate transition to “on air” may be 

necessary. The officer and driver shall don PPE and SCBA as soon as possible after arrival.

• At least one 13⁄4-inch handline should be placed on the ground, charged, and manned for 

emergency decontamination, chemical contaminant triage, and standoff protection. 

• Consider the use of positive pressure ventilation (PPV) to assist keeping the product in the hot 

zone [Fire and Rescue Departments of Northern Virginia 2014]. 

Once the initial size-up and risk assessment has been completed, the isolation zones are established, 

the strategy and incident action plan are defined and in place, the risk assessment becomes a 

continuous process. 

Electricity

A critical element of the emergency response to a propane or natural gas leak inside a structure is to

ensure that electricity is never turned on or off in a structure. This includes any other type of 

flammable gas leak or any type of flammable liquid leak inside a structure. 

If a leak is suspected/confirmed, the proper procedure is to evacuate all fire department members and 

secure the building. Incident commanders should request the response of the local power or utility 

company to secure or shut-off the power outside the hazard zone. 

 

Recommendation #2: Fire departments should ensure incident commanders initiate a defensive 

strategy and communicate the incident action plan (tactics) during initial operations of a hazardous 

materials incident. The strategy and IAP are revised based upon the tactical objectives taken to 

mitigate the hazard. 

Discussion: Unlike a fast paced, offensive structural firefighting incident, a hazmat incident should 

start out in the defensive strategy. Protective actions are those steps taken to preserve the health and 

safety of emergency responders and the public during an incident involving the release of hazardous 

materials. The specific IAP should identify the method of hazard control and the resources necessary to 

accomplish this goal. 

Overall operational strategies for a hazardous materials incident can be divided into the following 

categories: 

• Offensive operations: 

o Responders take direction action on the material, container, or equipment involved. This is 

a hazmat technician level operation, and a Site Safety Control Plan (ICS 208 HM) must be 

completed (See Appendix One). 

• Defensive operations 

o Responders seek to confine the incident in a given area without directly contacting the 

hazardous material involved. 

• Nonintervention operations: 

o Responders take no direct actions on the problem or situation. The main strategy for this 

incident would be to protect life and property by evacuation [IFSTA 2017]. 
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These separate strategies create a simple, understandable plan that describes how close the responders 

will get to the incident’s hazards. The overall strategic decision is based on the incident’s critical 

factors weighed against the risk management plan (e.g., risk a lot, risk a little, or risk nothing). 

The defined strategy describes the overall approach to incident operations and drives the IAP 

established by an incident commander at each incident. The IAP provides the tactical assignments 

required to achieve the offensive/defensive objective. The order of occurrence is key—the strategic 

goals are developed first followed by the tactical objectives that can be assigned to responding 

companies. At each incident, the incident commander should start with a standard placement-oriented 

operational plan that develops a strong, dependable foundation for command and control of the 

incident. This is the purpose of the IAP [Brunacini 2002; Brunacini, AV and Brunacini, N 2004; Blue 

Card 2018]. 

NFPA 1561 defines an IAP as a verbal plan, tactical worksheet, written plan, or combinations thereof 

that reflects the overall incident strategy, tactics, risk management, and firefighter safety that are 

developed by an incident commander. NFPA 1561, Standard on Emergency Services Incident 

Management System and Command Safety [NFPA 2020b] requires the following regarding an IAP: 

• 5.3.16.1. The incident commander shall be responsible for developing and/or approving an 

incident action plan (IAP). 

• 5.3.16.2. This IAP shall be communicated to all staged and assigned members at an incident.

• 5.3.16.3. For Type IV and Type V incidents, the incident commander shall communicate the 

IAP verbally to all on-scene resources.

• 5.3.24 The incident commander shall be responsible for reviewing, evaluating, and revising the 

IAP and overall strategy of the incident. 

All known hazmat incidents will start in the defensive strategy. 

The initial defensive tactical priorities include: 

• Define the hazard zone 

• Isolate the hazard zone

• Search and evacuate exposures 

• Protect exposures. [Blue Card 2018] 

The IC should follow the standard IAP for a hazmat incident: 

• Provide for the safety of all personnel and the public 

• Evacuate exposed areas if necessary 

• Identify and isolate the hot and warm zones 

• Deny entry 

• Attempt to identify the products involved 

• Upgrade the alarm assignment based on the incident’s hazard profile 

• Contain the release from a safe distance, and keep it from spreading 

• Protect exposures 

The IC can delegate responsibility to a geographic divisional or functional group supervisor. The 

specific supervisor is responsible for carrying out the tactics within their assignment. When a 
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supervisor completes or makes progress, they shall inform the incident commander with conditions, 

actions, and needs (CAN) report. For example, the incident commander assigns an officer as hazmat

group supervisor. The incident commander or hazmat group supervisor then assigns a hazmat entry 

leader to facilitate overall entry operations of assigned personnel within the exclusion or the hot zone. 

This entry leader gives updates through the hazmat group supervisor to Command on conditions, 

actions, and needs. Note: A hazardous materials decontamination leader or site access control leader 

can also perform these duties. When the command officer arrives on-scene, an update from the initial 

incident commander can occur (face-to-face or by radio). The command officer will then assume 

command at a stationary location. By following this process, the initial incident commander, and the 

subsequent incident commander will be in a stronger position to manage an emergency event during an

incident [FIRESCOPE 2017]. In addition to using a tactical worksheet, the hazmat group supervisor, 

and the hazmat assistant safety officer should develop and complete an ICS 208 Hazardous Materials 

(HM) Site Safety and Control Plan ICS Form 208 HM, Site Safety and Control Plan (fema.gov) (See 

Appendix One).

When a command officer (e.g., battalion chief, district chief, deputy chief, or fire chief) arrives onscene, he/she should automatically assume a standard stationary, exterior, and remote command 

position. The command officer will immediately assume Command and begin functioning as the 

incident commander. Command officers generally establish and continue command and control 

functions inside their vehicles or at the rear of the vehicle, which has a command board and/or a 

tactical worksheet. To effectively command an incident, the incident commander should be in the most 

advantageous position possible. The best position is a fixed, visible, and accessible location. This can 

be accomplished by utilizing the incident commander’s staff vehicle, a designated command vehicle, 

or fire apparatus. An acceptable alternative is utilizing the rear area of a sport utility vehicle or pick-up 

truck type vehicle. This method will provide the incident commander with an area that is quiet and free 

of distractions. It is vital for the incident commander to be able to hear all radio transmissions, 

especially from those operating in the hazard zone. The best way to accomplish this is using a radio 

communication headset. [NFPA 2020b]. 

With any plan, the first order of business is to move upwind and uphill. Evacuating the immediate and 

adjacent areas, establishing isolation zones through access control, and using the Emergency Response

Guide throughout the initial response are invaluable actions regardless of the level of threat [ERG 

2016]. 

After the product(s) of the release have been identified and the scope of the incident has been 

established, it is critical that Command make a resource determination based on the following: 

• Can the current level of dispatched resources adequately control the incident’s problems? 

• Is another agency required to control the incident’s problems (gas company, clean-up company, 

etc.)? 

• Does a hazmat unit (technician level or above) need to be consulted to control the incident’s 

problems? 

• Are additional technician level hazmat resources are needed to control the incident’s problems? 

• Is an entire hazmat team needed to control the incident’s problems [Blue Card 2018]? 
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Continuously performing size-up, evaluation, and revision, ensures that firefighters can operate safely, 

complete the tactical priorities, and go home unharmed after the event. This standard front-end 

approach ensures incident operations remain under control and assures incident operations occur 

within a structured plan. When the incident commander performs the standard command functions 

from the very beginning of the incident, it provides a basis for any revisions required to match the 

strategy and incident action plan to the current incident conditions. The ongoing evaluation of the 

incident’s critical factors is the basis for managing the current strategy and IAP and keeping it current 

(positions always match conditions). Hazmat incidents provide the incident commander with the 

discretionary time needed to make critical decisions.

The key to an appropriate hazmat response is to subscribe to a particular set of tactical responses, 

standardized in their approach and straightforward in their application. 

Recommendation #3: Fire departments should ensure firefighters are trained to understand the 

scrubbing or odorant fade of ethyl mercaptan from propane and natural gas. This training includes 

the use of multi-gas detectors to determine if a potential explosive atmosphere is present. 

Discussion: Prior to this incident, the propane supply line was severed on September 10, 2019, by a 

company that installed four bollards on Side Bravo of the office building parking lot. The bollards 

were 10 feet in length and one of the bollards the propane supply line when driven into the ground. 

Approximately 391 gallons leaked into the ground. The propane tank was filled again on September 

13, and approximately another 300 gallons leaked into the ground. During this time, no employees 

smelled ethyl mercaptan. 

Ethyl mercaptan is a clear liquid that is added to natural gas and propane to give it a distinct odor. The 

odor is described as smelling like a rotten egg or rotten cabbage. This liquid is added prior to 

transportation as a safety precaution to help detect a gas leak because natural gas and propane are 

odorless. Anosmia (inability to smell), hyposomnia (reduced sense of smell), and nasal inflammation 

can interfere with the ability to smell ethyl mercaptan [Roberson, E. 2001; NIOSH 2021]. 

The odor of ethyl mercaptan fades or is scrubbed due to oxidation, adsorption, or absorption. Leaking 

natural gas or propane from underground lines loses the odor of ethyl mercaptan as it passes through 

soils and concrete. Materials such as drywall, plywood, and new piping for natural gas or propane will 

also adsorb the odor until the material becomes saturated. See Safety Advisory: Odor Fade in Nature 

Gas and Propane, DHHS (NIOSH) Publication Number 2021-106 | NIOSH | CDC. Odor fade is 

generally more common in new, large-diameter steel pipes and storage tanks; however, odor fade can 

also occur in smaller- diameter gas lines made of polyethylene. For new natural gas or propane 

installations, many gas installation companies perform pipe pickling or pipeline conditioning to 

saturate the new gas installations prior to use. Likewise, new storage tanks and new components of 

natural gas or propane installations should be conditioned prior to use [CPSC 1987]. 

On the morning of September 16, 2019, a maintenance worker was moving tables to the basement of 

the office building. He complained of dizziness and being light-headed. The maintenance supervisor 

called the fire and rescue department at 0806 hours. When the fire and rescue department arrived on-
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scene and firefighters started their investigation, no one smelled ethyl mercaptan. The facility 

maintenance work and several firefighters noticed frost on the bottom portion of the tank and the 

ground underneath the propane tank. The building exploded at approximately 0817 hours. 

During the investigation conducted by the Maine Office of the State Fire Marshal, investigators dug up 

the propane supply line two days later and found a high concentration of ethyl mercaptan in the soil. 

The soil, concrete, and building materials absorbed the propane creating odorant fade. Propane has an 

expansion ratio of 270:1. The vapor density of propane is 1.56, making it heavier than air. Propane will 

seek low areas and accumulate until it dissipates or finds an ignition source. Propane has a LEL of 2.3 

and an upper explosion limit (UEL) of 9.5, and one gallon of liquid weighs 4.23 pounds. Propane has 

an ignition temperature between 920° F and 1,120° F [FRDNV 2014, Airgas 2018] (See Appendix 

Two). 

Propane in its natural form is colorless and odorless and ethyl mercaptan is added to propane for leak 

detection. Department of Transportation requires any combustible/flammable gas in a distribution line 

to be odorized or have a natural odorant. It states that a person with a normal sense of smell should be 

able to detect a concentration in air of 20% of the lower explosive limit. The mercaptan is added at a 

rate of one pound per 10,000 gallons of liquid propane. This equates to a one part per billion. The

odorization of propane is addressed by a myriad of Federal and State laws and regulations, as well as, 

by accepted industry standards and practices. When offered and transported in commerce, the 

Hazardous Materials Regulations specifies that all propane in cargo and portable tanks be effectively 

odorized using either 1.0 pound of ethyl mercaptan, 1.0 pound of thiophane, or 1.4 pounds of amyl 

mercaptan per 10,000 gallons of propane, in the event of an unintended release or leak to indicate the 

presence of gas. The Hazardous Materials Regulations do not, however, require propane to be odorized 

if odorization would be harmful in the use or further processing of the propane, or if odorization will 

serve no useful purpose as a warning agent in such use or further processing. Essentially, this 

exception applies to propane being transported to industrial end-users [Federal Register 2013]. 

Training on sampling, monitoring, and detection is a critical component of this process. Firefighters 

trained to the Operations Level of 29 CFFR 1910.120, HAZWOPER, can conduct atmospheric 

monitoring with a multi-gas detector designed to monitor oxygen levels, presence of carbon monoxide, 

hydrogen sulfide, and LEL of flammable gases. Annual continuing education training provides 

opportunities for firefighters and fire officers to maintain their competencies for sampling, monitoring, 

and detection at a hazardous materials incident. The training should include discussion regarding the 

use of turnout gear and SCBA during the sampling, monitoring, and detection function. 

Recommendation #4: Fire departments should ensure that firefighters wear proper PPE including 

SCBA when entering an IDLH environment involving propane and natural gas. 

Discussion: NFPA 1500, Standard on Fire Department Occupational Safety, Health, and Wellness 

Program states in Paragraph 7.1.1.1, “A risk assessment for the need and, if necessary, selection of 

protective ensembles, ensemble elements, and protective equipment shall be conducted in accordance 

with 29 CFR 1910.132, Personal Protective Equipment.” In Paragraph 7.1.1.2, “The selection of 

applicable protective ensembles, ensemble elements, and other protective equipment shall be based on 
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a selection program containing a risk assessment in compliance with 29 CFR 1910.132, Personal 

Protective Equipment and all applicable NFPA standards.” In Paragraph 7.1.2, “Protective ensembles, 

ensemble elements, and other protective equipment shall be used whenever the member is exposed or 

potentially exposed to the hazards for which it is provided.” Also, in Paragraph 7.1.3 of NFPA 1500, 

states, “The fire department shall require all members to wear or use all protective ensembles, 

ensemble elements, and other protective equipment specific to the operation in which members are 

engaged” [NFPA 2021]. 

With the development of a defensive strategy and the incident action plan for an incident with a report 

on an odor of propane, the process starts at the hazmat operations level. All members should be in a 

minimum of full structural protective clothing including SCBA. Personnel working in a suspected 

ignitable atmosphere should be backed up by a staffed protective hand line, which should be at a 

minimum of 13⁄4-inch hoseline. The number of exposed personnel will be kept to an absolute minimum 

[FRDNV 2014; NFD 2007]. 

Recommendation #5: Fire departments should have a SOP/SOG (standard operating 

procedure/standard operating guideline) for conducting sampling, detection, and monitoring at 

propane and natural gas emergencies. 

Discussion: For all propane and natural gas emergencies, fire departments should develop and 

implement a SOP/SOG for this process that is compliant with OSHA requirements. There should be at 

least two 4-gas meters (oxygen levels, presence of carbon monoxide, hydrogen sulfide, and LEL of 

flammable gases – O2, CO, H2S, and LEL) placed in operation by the engine company or truck 

company firefighters. Firefighters should obtain enough gas concentration readings for Command to 

evaluate the hazard and take appropriate action. These readings are used to define a proper isolation 

perimeter and the isolation zones (hot, warm, and cold) [FRDNV 2014]. The standard response action 

for isolation zones is defined by OSHA 1910.120 – HAZWOPER. 

Monitoring is conducted in a methodical process with firefighters operating in full PPE, including 

SCBA. Also, a covering hoseline should be deployed to protect the firefighters conducting the 

monitoring. The first meter readings should be taken on the exterior of the building. These readings 

will determine the course of action. [VBFD 2019b, VBFD 2019c] (See Appendix Three). 

Multi-gas meters measure a percentage of the LEL. Readings should be interpreted as follows: 

• Atmospheres where the quantity of flammable/explosive gas is less than 10% of the LEL, 

personnel may, with caution, continue to mitigate the hazard. 

• Atmospheres where the quantity of flammable/explosive gas is between 10% and 25% of the 

LEL, continuous monitoring and the full ensemble of personal protective equipment is 

required. Personnel may continue with caution to operate seeking the source or mitigating the 

hazard. 

• Atmospheres where the quantity of flammable/explosive gas is greater than 25% of the LEL, 

personnel shall immediately withdraw from the area to the cold zone and consult the expert 

advice of the HAZMAT team. In addition to a withdrawal, the tactical considerations should 
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include ventilation or the application of Class B foam to fuel spills for vapor suppression 

[VBFD 2019a]. 

Any incident that involves a potential hazardous atmosphere is the responsibility of the fire 

department. The first arriving resource should establish command and work within the scope of their 

training, initially taking the actions to determine the scope of the situation requiring an emergency 

response. A key component of this process is to identify the need for additional resources early in the 

incident. 

After the product(s) of the release have been identified and the scope of the incident has been 

established, it is critical that Command make a resource determination based on the following: 

• Can the current level of dispatched resources adequately control the incident’s problems? 

• Is another agency required to control the incident’s problems (gas company, clean-up company, 

etc.)?

• Does a hazmat unit (tech level or above) need to be consulted to control the incident’s 

problems? 

• Are additional technician level hazmat resources needed to control the incident’s problems? 

• Is an entire hazmat team needed to control the incident’s problems [Blue Card 2018]? 

If the decision is made to put firefighters on the inside of the building, this causes a revision to the 

strategy and IAP. Also, this should require a change from the hazmat operations level to the hazmat 

technician level. Command needs to communicate this to all firefighters and other first responders onscene [Blue Card 2018]. 

Recommendation #6: Fire departments should ensure that firefighters are properly trained and 

certified to understand the capabilities of the department’s multi-gas detectors, especially catalytic 

LEL combustible gas senor performance.

Discussion: Understanding how combustible sensors detect gas is critical to correctly interpreting 

readings and avoiding misuse of instruments that include a LEL combustible gas sensor. 

Different gases and vapors have different LEL concentrations. Below the LEL, the ratio of combustible 

gas molecules to oxygen is too low for combustion to occur. In other words, the mixture is "too lean" 

to burn. Most (but not all) combustible gases and vapors also have an upper limit of concentration 

beyond which ignition will not occur. The UEL is the maximum concentration of combustible gas or 

vapor in air that will support combustion. Above the UEL, the ratio of gas to oxygen is too high for the 

fire reaction to propagate. In other words, the mixture is "too rich" to burn. The difference in 

concentration between the LEL and UEL is commonly referred to as the flammability range. 

Combustible gas concentrations within the flammability range will burn or explode provided that the 

other conditions required in the fire tetrahedron (adequate oxygen, adequate fuel, a source of ignition, 

and sufficient molecular energy to sustain the fire chain reaction) are met [AP 1018 2013]. 
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Whenever readings exceed 10% LEL an explosion and fire hazard is possible. This is the least 

conservative (or highest acceptable) alarm set point for instruments used for monitoring combustible 

gases and vapors. 

Catalytic-bead sensors require at least eight to ten percent oxygen by volume to detect accurately. A 

combustible sensor in a 100% gas or vapor environment will likely produce a reading of zero percent 

LEL. This is the reason that testing protocols for evaluating confined spaces specify measuring oxygen 

first and then combustible gases and vapors. For this reason, confined space instruments that contain 

catalytic-bead sensors should also include a sensor for measuring oxygen. If the instrument being used 

does not include an oxygen sensor, the firefighter should be especially cautious when interpreting 

results. A rapid up-scale reading followed by a declining or erratic reading may indicate that the 

environment contains insufficient oxygen for the sensor to read accurately. It may also indicate a gas 

concentration beyond the upper scale limit for the sensor, the presence of a contaminant which has 

caused a sudden inhibition or loss of sensitivity in the sensor, or other conditions which prevent the 

sensor or instrument from obtaining proper readings [AP 1018 2013]. 

A combustible gas sensor may be calibrated to any number of different gases or vapors. Where 

possible, the user should calibrate the instrument to achieve the level of sensitivity required for the 

substances to be measured (Note: See Recommendation 7). When interpreting the reading on a 

combustible gas indicator, the readings represent the percentage of LEL. 

The important thing to remember is that the LEL is stated as a percentage of concentration of a gas in 

the atmosphere while the meter reading displayed is a percentage of the specified LEL concentration. 

Because methane has an LEL of 5 percent concentration in air, a reading of “10” indicates that the 

concentration is only 10 percent (or 1/10th) of the 5 percent concentration in air that would be needed 

to reach the LEL. Likewise, a reading of “5” indicates that the concentration is only 5 percent (or 

1/20th) of the concentration needed to reach the 5 percent LEL.

 

Regardless of the LEL value, a reading of 10 percent or more of that value is cause for concern, as 

stated in OSHA Standard 29 CFR 1910.146, Permit-Required Confined Spaces, which considers 10 

percent or more of any LEL to be a hazardous atmosphere [OSHA 1993]. 

As with the readings discussed earlier for methane, for this particular gas, a reading of 5 percent LEL 

is 1/20th of the concentration in air that would be needed to reach the LEL (1/20th of 20 percent LEL 

is equal to 1 percent concentration). Likewise, a reading of 25 percent LEL is equal to 1/4th of the LEL 

concentration of 20 percent, or a 5 percent concentration of the gas in the atmosphere [See Chart 1] 

[De Lisi 2010]. 
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Another concern with using a combustible gas indicator is that readings provided by the monitor are 

accurate only when attempting to measure the same gas used during calibration procedures. Since the 

sensitivity of combustible gas sensors varies with exposure to different types of atmospheres, any 

attempt to measure the concentration of gases other than that used during calibration will result in a 

reading that is likely greater or less than the actual concentration. Remedying this situation will require 

the use of a correction factor or relative response curve specific to the gas or vapor measured to obtain 

more accurate results [De Lisi 2010]. To better understand this, consider an analogy to time zones 

where a clock set to Eastern Standard Time in New York is accurate only in that time zone. To use that 

same clock in California, you would have to subtract three hours from the time displayed. 

 

Some atmospheric monitors can perform these adjustments internally based on the appropriate relative 

response or correction factor. To ensure proper adjustment, it may be necessary to compare the 

displayed reading on some instruments to a chart or graph provided by the manufacturer, and then 

manually calculate the actual reading [De Lisi 2010]. For example, if a combustible gas indicator of an 

atmospheric monitor is calibrated with methane, readings when the instrument is used to detect 

methane will be “correct.” However, if this same instrument is used to detect the presence of propane 

gas, it is necessary to use a correction factor. 

 

If the correction factor for propane is “1.5,” all readings obtained with the atmospheric monitor when 

measuring propane must then be multiplied by 1.5. Therefore, a reading of 1 percent LEL is actually 

1.5 % of the LEL, whereas a reading of 6 percent LEL is actually 9 % of the LEL, determined by 

multiplying 6 percent x 1.5. Likewise, when using an atmospheric monitor calibrated to methane to 

Chart 1. A chart based on a gas with a LEL of 20 percent and is read left to right.
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measure the concentration of gasoline vapors, calculations using a correction factor will be necessary 

to adjust the readings accordingly [De Lisi 2010]. 

 

Recommendation #7: Fire departments should ensure that multi-gas detectors are properly 

maintained per the manufacturer’s recommendations. 

Discussion: The calibration process is important to maintaining and operating a multi-gas detector. Fire 

department members should have a thorough understanding of the selection, care, and maintenance of 

multi-gas detectors. Most importantly, firefighters and other first responders should follow the 

manufacturer’s use and maintenance guidelines to ensure the multi-gas detector will operate as 

intended. Using the multi-gas detector and understanding the sensor technology using LEL is an 

important component of air sampling and air monitoring. The oxygen level is very significant to the 

detection of the LEL [ISEA 2010]. 

Calibration is a two-step procedure. In the first step the instrument is exposed to contaminant free 

"fresh" air (that is, air which contains 20.9 % oxygen and no combustible gas), turned on, and allowed 

to warm-up fully. The combustible sensor should read zero. If necessary, the combustible sensor is 

adjusted to read zero. Instrument manuals and other support materials usually refer to this step as the 

"fresh air zero." The second step is to expose the sensor to a known concentration of calibration gas, 

and (if necessary) adjust the readings to match the concentration. This is called making a "span 

adjustment." A "span adjustment" sets the sensitivity of the sensor to a specific gas. Always follow the 

manufacturer's instructions when calibrating or adjusting the instrument [AP1018 2021]. 

Bump testing and calibration testing are essential for fire departments that operate direct-reading 

portable multi-gas detectors to check oxygen levels and monitor for toxic or combustible gases. A 

bump test determines whether a direct-reading portable multi-gas detector can detect the presence of a 

possibly hazardous gas. The bump test is simple and should only take about one minute. The test 

should be performed daily prior to use of each installed sensor. A full calibration should be performed 

at least monthly to ensure direct-reading portable multi-gas detector equipment is accurate.

 

Direct-reading portable multi-gas detectors fall under the guidance of the International Safety 

Equipment Association [ISEA]. In 2010, the ISEA released a statement on how to improve consistency 

in the use, testing, and proper maintenance of direct-reading portable multi-gas detectors. The 

statement discussed the differences between a bump test (calibration check) and full calibration test 

plus how and when to conduct each test [ISEA 2010]. 

The ISEA definitions are: 

• Bump Test (Function Check) - A qualitative function check where a challenge gas is

passed over the sensor(s) at a concentration and exposure time sufficient to activate all 

alarm indicators to present at least their lower alarm setting. The purpose of this check is to

confirm that gas can get to the sensor(s) and that all the alarms are functional. This 

is typically dependent on the response time of the sensor(s) or a minimum level of response 

achieved, such as 80% of gas concentration applied. Note this check is not intended to provide 

a measure of calibration accuracy.
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• Calibration Check - A quantitative test utilizing a known traceable concentration of test gas

to demonstrate that the sensor(s) and alarms respond to the gas within manufacturer’s 

acceptable limits. This is typically ±10-20% of the test gas concentration applied unless 

otherwise specified by the manufacturer, internal company policy, or a regulatory agency. 

• Full Calibration – The adjustment of the sensor(s) response to match the desired value 

compared to a known traceable concentration of test gas. This should be done in accordance 

with the manufacturer's instructions [ISEA 2010]. 

According to manufacturer’s instructions, users should perform a bump test and calibration check 

every day before anyone uses the direct-reading portable multi-gas. The direct-reading portable multigas detector’s manufacturer’s guidelines—plus internal fire department procedures and OSHA 

regulatory requirements—determine exactly how and how often to fully calibrate direct-reading 

portable multi-gas detectors. Full calibration is also necessary if a bump test or calibration check fails. 

You can perform a full calibration twice, but after two “fails,” the device must be pulled from use. Full 

calibrations should also take place after the following types of exposures: 

• Different operator or working environment 

• Extreme environmental, storage, and operating conditions 

• Highly concentrated target gases and vapors

• Solvent vapors and corrosive gases 

• Poisons and inhibitors [OSHA 2013].

When testing a device, use the following guidelines: 

• Perform the calibration in fresh air

• Choose a test environment with conditions that match your workplace 

• Use a recommended gas mixture, which should meet the National Institute of Standards and 

Technology 

• Check the gas’s expiration date 

• Always refer to your product manual for specifics [OSHA 2014]. 

The atmosphere in which an instrument is used can have an effect on catalytic-bead sensors. Poisoning 

or degraded performance can occur when combustible sensors are exposed to certain substances. 

Commonly encountered substances that degrade LEL sensor performance include silicones, lead 

containing compounds (especially tetraethyl lead), sulfur containing compounds, substances containing 

phosphorus and halogenated hydrocarbons. Combustible sensors can also be affected by exposure to 

high concentrations of ignitable mixtures. 

Age and usage can also affect the sensitivity of combustible sensors. Chronic exposure to low levels of 

poisons or inhibitors acts cumulatively. This usually means that the sensitivity must be increased when 

calibration occurs. In the extreme, the sensor may require replacement. This again demonstrates that 

regular calibration is essential to the safe use of combustible sensors. 

For many combustible sensors, if sensitivity is lost due to poisoning, it tends to be lost first with 

regards to methane. This means that a partially poisoned sensor might still respond accurately to other 

combustible gases while showing a significantly reduced response to methane. This is a particularly 
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important concern for instruments used to monitor atmospheres associated with confined spaces, where 

methane is by far the most encountered combustible gas [AP1018 2013]. 

Employers should keep calibration records for the life of each instrument. This record enables 

operators to quickly identify a direct-reading portable gas monitor that has a history of excessive 

maintenance/repair, or is prone to erratic readings, and to track drift of the sensors to determine when 

they need replacement [OSHA 2013]. Even without an incident, testing and maintenance data can track 

other valuable information, and new technology makes recordkeeping easier and more valuable than 

ever. Digital tracking and remote monitoring are just some newer technologies that automatically track 

and allow the user to manage the department’s bump tests and calibrations. Some direct-reading 

portable multi-gas detectors can even be paired with GPS devices so that Command always knows 

where firefighters are located. If firefighters have been exposed or if a man-down alarm indicates that a 

firefighter experienced a health emergency, Command knows exactly where to send help and what 

kind of help to send. 

Recommendation #8: Fire departments that respond to propane and natural gas emergencies should 

comply with the requirements of 29 CFR Part 1910.120, Hazardous Waste Operations and 

Emergency Response.

Discussion: Hazardous materials training and certification is completed through the Maine Emergency 

Management Agency, State Emergency Response Commission (SERC). The SERC supports training 

of first responders and emergency managers across the state. Training is coordinated regionally 

through the 16-county based local emergency planning committee. The SERC offers the following 

hazardous materials training, which complies with 29 CFR 1910.120, Hazardous Waste Operations 

and Emergency Response: 

• First Responder Awareness Level

• Hazardous Materials Operations Level

• Hazardous Materials Technician Level

• Hazardous Materials Specialist

The necessary components of 29 CFR 1910.120, Hazardous Waste Operations and Emergency 

Response that need to be addressed include: 

• Occupational Safety and Health Program. Each hazardous waste site mitigation and clean-up 

effort will require a site-specific occupational safety and health program headed by the site 

coordinator or the employer's representative. The purpose of the program will be the protection 

of employees at the site and will be an extension of the employer's overall safety and health 

program work. It will provide the overall means for planning and implementing the needed 

safety and health training and job orientation of employees who will be working at the site. The 

program will provide the means for identifying and controlling worksite hazards and for 

monitoring program effectiveness. The program will need to cover the responsibilities and 

authority of the site coordinator for the safety and health of employees at the site, and the 

relationships with contractors or support services as to what each employer's safety and health 

responsibilities are for their employees on the site [OSHA 1990]. 
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• Training. The training programs for employees to fulfill the requirements of paragraph (e) of 

this standard (included below) should address: the safety and health hazards employees should 

expect to find on hazardous waste clean-up sites; what control measures or techniques are 

effective for those hazards; what monitoring procedures are effective in characterizing exposure 

levels; what makes an effective employer's safety and health program; what a site safety and 

health plan should include; hands on training with personal protective equipment and clothing 

they may be expected to use; the contents of the OSHA standard relevant to the employee's 

duties and function; and employee's responsibilities under OSHA and other regulations. 

Supervisors will need training in their responsibilities under the safety and health program and 

its subject areas such as the spill containment program, the personal protective equipment 

program, the medical surveillance program, the emergency response plan, and other areas.

o 1910.120(e)(3) 

Initial training. 

1910.120(e)(3)(i) 

General site workers (such as equipment operators, general laborers, and supervisory 

personnel) engaged in hazardous substance removal or other activities which expose or 

potentially expose workers to hazardous substances and health hazards shall receive a

minimum of 40 hours of instruction off the site, and a minimum of three days actual 

field experience under the direct supervision of a trained experienced supervisor. 

o 1910.120(e)(3)(iii) 

Workers regularly on site who work in areas which have been monitored and fully 

characterized indicating that exposures are under permissible exposure limits and 

published exposure limits where respirators are not necessary, and the characterization 

indicates that there are no health hazards or the possibility of an emergency developing, 

shall receive a minimum of 24 hours of instruction off the site, and the minimum of one 

day actual field experience under the direct supervision of a trained, experienced 

supervisor. 

o 1910.120(e)(3)(iv) 

Workers with 24 hours of training who are covered by paragraphs (e)(3)(ii) and 

(e)(3)(iii) of this section, and who become general site workers or who are required to 

wear respirators, shall have the additional 16 hours and two days of training necessary 

to total the training specified in paragraph (e)(3)(i).

o 1910.120(e)(7)

Emergency response. Employees who are engaged in responding to hazardous 

emergency situations at hazardous waste clean-up sites that may expose them to 

hazardous substances shall be trained in how to respond to such expected emergencies.

o 1910.120(e)(8)

Refresher training. Employees specified in paragraph (e)(1) of this section, and 

managers and supervisors specified in paragraph (e)(4) of this section, shall receive 

eight hours of refresher training annually on the items specified in paragraph (e)(2) 

and/or (e)(4) of this section, any critique of incidents that have occurred in the past year 

that can serve as training examples of related work, and other relevant topics.

o 1910.120(e)(9)

Equivalent training. 
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Employers who can show by documentation or certification that an employee's work 

experience and/or training has resulted in training equivalent to that training required in 

paragraphs (e)(1) through (e)(4) of this section shall not be required to provide the 

initial training requirements of those paragraphs to such employees and shall provide a 

copy of the certification or documentation to the employee upon request. However, 

certified employees or employees with equivalent training new to a site shall receive 

appropriate, site specific training before site entry and have appropriate supervised field 

experience at the new site. Equivalent training includes any academic training or the 

training that existing employees might have already received from actual hazardous 

waste site experience [OSHA 1990].

Note: National Fire Protection Association standards NFPA 472, Standard for Competence of 

Responders to Hazardous Materials/Weapons of Mass Destruction Incidents and NFPA 1072, 

Standard for Hazardous Materials/Weapons of Mass Destruction Emergency Response Personnel 

Professional Qualifications are excellent resource documents to aid fire departments and other 

emergency response organizations in developing their training program materials. NFPA 472 provides 

guidance on the skills and knowledge needed for first responder awareness level, first responder 

operations level, HAZMAT technicians, and HAZMAT specialist. It also offers guidance for the officer 

in charge of a hazardous material incident. NFPA 1072 identifies the job performance requirements 

for personnel at the scene of a hazardous materials/weapons of mass destruction incident, including 

the following levels: awareness, operations, operations specific, hazardous materials technician, and 

incident commander [NFPA 2018b, NFPA 2017b].

• Decontamination. Decontamination procedures should be tailored to the specific hazards of the 

site and will vary in complexity and number of steps, depending on the level of hazard and the 

employee's exposure to the hazard. Decontamination procedures and PPE decontamination 

methods will vary depending upon the specific substance, since one procedure or method will 

not work for all substances. Evaluation of decontamination methods and procedures should be 

performed, as necessary, to assure that employees are not exposed to hazards by reusing PPE. 

References in Appendix D may be used for guidance in establishing an effective 

decontamination program. In addition, the United States Coast Guard's Manual, Policy 

Guidance for Response to Hazardous Chemical Releases, United States Department of 

Transportation, Washington, DC (COMDTINST M16465.30) is a good reference for 

establishing an effective decontamination program [OSHA 1990].

• Emergency Response Plans. States, along with designated districts within the states, will be 

developing or have developed emergency response plans. These state and district plans should 

be utilized in the emergency response plans called for in the standard. Each employer should 

assure that its emergency response plan is compatible with the local plan. The major reference 

being used to aid in developing the state and local district plans is the Hazardous Materials 

Emergency Planning Guide, NRT - 1. The current Emergency Response Guidebook from the 

U.S. Department of Transportation, CMA's CHEMTREC and the Fire Service Emergency 

Management Handbook may also be used as resources.
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Employers involved with treatment, storage, and disposal facilities for hazardous waste, which 

have the required contingency plan called for by their permit, would not need to duplicate the 

same planning elements. Those items of the emergency response plan may be substituted into 

the emergency response plan required in 1910.120 or otherwise kept together for employer and 

employee use [OSHA 1990].

• Monitoring. Frequency and types of air monitoring, personnel monitoring, and environmental 

sampling techniques and instrumentation to be used, including methods of maintenance and 

calibration of monitoring and sampling equipment to be used. Note: See Recommendation #6 

and Recommendation #7. 

•

Monitoring the air with appropriate direct reading test equipment for (i.e., combustible gas 

meters, detector tubes) for IDLH and other conditions that may cause death or serious harm 

(combustible or explosive atmospheres, oxygen deficiency, toxic substances.) Visually 

observing for signs of actual or potential IDLH or other dangerous conditions [OSHA 1990].

• Personal Protective Equipment Programs. The purpose of personal protective clothing and 

equipment (PPE) is to shield or isolate individuals from the chemical, physical, and biologic 

hazards that may be encountered at a hazardous substance site.

As discussed in Appendix B of 29 CFR 1910.120, no single combination of protective 

equipment and clothing can protect against all hazards. Thus, PPE should be used in 

conjunction with other protective methods and its effectiveness evaluated periodically.

The use of PPE can itself create significant worker hazards, such as heat stress, physical and 

psychological stress, and impaired vision, mobility, and communication. For any given 

situation, equipment and clothing should be selected that provide an adequate level of 

protection. However, over-protection, as well as under-protection, can be hazardous and should 

be avoided where possible. Two basic objectives of any PPE program should be to protect the 

wearer from safety and health hazards, and to prevent injury to the wearer from incorrect use 

and/or malfunction of the PPE. To accomplish these goals, a comprehensive PPE program 

should include hazard identification, medical monitoring, environmental surveillance, selection, 

use, maintenance, and decontamination of PPE and its associated training.

The written PPE program should include policy statements, procedures, and guidelines. Copies 

should be made available to all employees, and a reference copy should be made available at 

the worksite. Technical data on equipment, maintenance manuals, relevant regulations, and 

other essential information should also be collected and maintained [OSHA 1990].

• Incident Command System (ICS). Paragraph 1910.120(q)(3)(ii) requires the implementation of 

an incident command system. The ICS is an organized approach to effectively control and 

manage operations at an emergency incident. ICS is implemented for emergency response to all 

incidents, both large and small, that involve hazardous materials.

The Incident Command System (ICS) is a management system designed to enable effective and 

efficient domestic incident management by integrating a combination of facilities, equipment, 
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personnel, procedures, and communications operating within a common organizational 

structure. ICS is normally structured to facilitate activities in five major functional areas: 

command, operations, planning, logistics, finance, and administration. It is a fundamental form 

of management, with the purpose of enabling incident managers to identify the key concerns 

associated with the incident—often under urgent conditions—without sacrificing attention to 

any component of the command system. Officers who may be expected to be in charge at an 

incident should be fully knowledgeable of their department’s incident command system. They 

should know where and how to obtain additional assistance and be familiar with the local 

district's emergency response plan and the state emergency response plan [OSHA 1990].

Note: NFPA 1561, Standard on Emergency Services Incident Management System and Command 

Safety serves as an excellent resource on how to effectively command and control and emergency 

incident including a hazardous materials incident.

• Site Safety and Control Plans. The safety and security of response personnel and others 

operating at an emergency response incident site should be of primary concern to the incident 

commander. The use of a site safety and control plan could greatly assist those in charge of 

assuring the safety and health of employees on the site.

A comprehensive site safety and control plan [using the ICS Form 208 HM] ICS Form 208 

HM, Site Safety and Control Plan (fema.gov) should include the following: summary analysis 

of hazards on the site and a risk analysis of those hazards; site map or sketch; site work zones 

(clean zone, transition or decontamination zone, work or hot zone); use of the buddy system; 

site communications; command post or command center; standard operating procedures and 

safe work practices; medical assistance and triage area; hazard monitoring plan (air 

contaminate monitoring, etc.); decontamination procedures and area; and other relevant areas. 

This plan should be a part of the employer's emergency response plan or an extension of it to 

the specific site [OSHA 1990].

• Medical surveillance programs. Workers handling hazardous substances may be exposed to 

toxic chemicals, safety hazards, biologic hazards, and radiation. Therefore, a medical 

surveillance program is essential to assess and monitor workers' health and fitness for 

employment in hazardous waste operations and during the course of work; to provide 

emergency and other treatment as needed; and to keep accurate records for future reference.

The medical surveillance program shall be instituted by the employer for the following 

employees: 

o All employees who are or may be exposed to hazardous substances or health hazards at or 

above the established permissible exposure limit, above the published exposure levels for 

these substances, without regard to the use of respirators, for 30 days or more a year.

o All employees who wear a respirator for 30 days or more a year or as required by 29 CFR

1910.134.

o All employees who are injured, become ill or develop signs or symptoms due to possible 

overexposure involving hazardous substances or health hazards from an emergency 

response or hazardous waste operation and members of HAZMAT teams. 
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o Medical examinations and consultations shall be made available by the employer to each 

employee prior to assignment and at least once every twelve months for each employee 

covered unless the attending physician believes a longer interval (not greater than 

biennially) is appropriate [OSHA 1990]. 

Note: This should include a health maintenance program which meets the requirements of NFPA 

1582, Standard on Comprehensive Occupational Medical Program for Fire Departments. 

• Recordkeeping. Training providers should maintain records listing the dates courses were 

presented, the names of the individual course attendees, the names of those students 

successfully completing each course, and the number of training certificates issued to each 

successful student. These records should be maintained for a minimum of five years after the 

date an individual participated in a training program offered by the training provider. These 

records should be available and provided upon the student's request or as mandated by law 

[OSHA 1990]. 

Recommendation #9: Fire departments should use a personnel accountability system requiring a 

check-in and check-out procedure with a designated accountability officer or the incident 

commander. 

Discussion: Note: Although there is no evidence that the following recommendation would have 

prevented this fatality, it is being provided as a reminder of a critical firefighter safety component to be 

to be utilized during incident operations. At this incident, arriving first responders were tasked with

locate and accounting the initial responding firefighters and office employees. This process took 

approximately 30 minutes to complete. There was an influx of first responders and citizens that were 

not accounted for initially until the deputy chief arrived on-scene and established a designated 

accountability officer. 

A personnel accountability system is a system that readily identifies both the location and function of 

all members operating at an incident scene [NFPA 2021]. The philosophy of the personnel 

accountability system starts with the same principles of an incident management system—company 

unity and unity of command. Unity can be fulfilled initially and maintained throughout the incident by 

documenting the situation status and resource status on a tactical worksheet. 

An integral part of the accountability system is to make sure that the firefighters assigned and 

operating in the hazard zone are accounted for, starting with the initial operations through the entire 

incident. Also, a process should be in place to periodically make sure that all members operating in the 

hazard zone are accounted for by this system. 

 

NFPA 1561, Standard on Emergency Services Incident Management System and Command Safety, 

states in Paragraph 8.12.4, “The incident commander and members who are assigned a supervisory 

responsibility that involves three or more companies or crews under their command shall have an 

additional member(s) (e.g., staff aide) assigned to facilitate the tracking and accountability of the 

assigned companies or crews” [NFPA 2020b]. 
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A functional personnel accountability system requires the following: 

• Development and implementation of a departmental standard operating procedure/standard 

operating guideline

• Necessary components and hardware, such as an accountability board, individual name tags, 

and company name tags

• Training for all members on the operation of the system

• Strict enforcement during emergency incidents.

A functional personnel accountability system should be able to identify:

• all members operating in the hazard zone (who)

• the location of all members in the hazard zone (where)

• the conditions in the hazard zone (conditions)

• the actions being taken in the hazard zone (actions)

• the paths of access and egress in and out of the hazard zone (exits)

• and assign rapid intervention crew(s) (RIC).

There are many different methods and tools for resource accountability. Some examples are: 

• Tactical worksheets

• Command boards 

• Apparatus riding lists 

• Company responding boards 

• Electronic bar-coding systems 

• Accountability tags or keys (e.g., PASSPORT System) [NFPA 2020b]. 

Resource accountability should be assigned to personnel who are responsible for maintaining the 

location and status of all assigned resources at an incident. As the incident escalates, resource status 

would be placed under the Planning Section. This function is separate from the role of the incident 

commander who is responsible for the overall command and control of the incident. Due to the 

importance of responder safety, resource status should be assigned to a dedicated member as the size 

and complexity of the incident dictates. Several positions could function in this role including an 

incident command technician, staff assistant, chief officer, or other designated member. As the incident 

escalates and tactical-level management components (e.g., divisions or groups) are assigned, the 

resource status officer (accountability officer) works with the division or group supervisors to maintain 

an on-going tracking and accountability of members [FIRESCOPE 2015]. A properly initiated and 

enforced personnel accountability system enhances firefighter safety and survival. 

An important aspect of a personnel accountability system is the personnel accountability report, an onscene roll call in which each supervisor reports the status of their crew when requested by the incident 

commander [NFPA 2020b]. The personal accountability report should be conducted every 15–20 

minutes or when benchmarks are met. 

For the personnel accountability system to properly function, the process should include a SOP/SOG

that defines each function’s responsibility and the necessary hardware required to ensure this process is 
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successful on the fireground. Also, a training component, including both classroom and practical, 

should be conducted to ensure this process functions properly during emergency incidents. 

Recommendation #10: Fire departments should develop and implement a SOP/SOG on the use and 

deployment of rapid intervention crews.

Discussion: Note: Although there is no evidence that the following recommendation would have 

prevented this fatality, it is being provided as a reminder of a critical firefighter safety component to be 

to be utilized during incident operations. In order to ensure compliance with 29 CFR 1910.134 

Respiratory Protection [OSHA 1998], fire departments must maintain a rapid intervention crew (RIC) 

or company when members are operating in an IDLH or potentially IDLH atmosphere [NFPA 2018]. 

In some organizations, they can be known as a rapid intervention team or firefighter assist and search 

team (FAST).

The RIC function should be incorporated into the department’s incident management system and the 

personnel accountability system [NFPA 2020a]. The needs of critical fireground operations and 

staffing should be continuously evaluated regarding firefighter safety. Resource assignments should 

always be made with the goal of having the RIC function in place. When the incident commander 

needs additional resources, the consideration of deploying the RIC for an operational assignment 

without additional resources on-scene to function as the RIC should be carefully assessed [NFPA 

2020a]. 

The following restrictions regarding the use of RIC/FAST should be considered by the incident 

commander during fireground operations: 

• The RIC should not be used for firefighting operations 

• The RIC is dedicated to assist and, if necessary, rescue members who become lost, trapped, 

distressed, or involved in other serious life-threatening situations 

• The RIC should not be used to provide relief for operating companies until the fire/incident has 

been declared “under control” by Command 

• If assigned by a superior officer to other than RIC duties, the RIC unit officer should remind 

such officer of RIC designation [Toledo Fire & Rescue Department 2012; TSFRS 2014]. 

When incident commanders order the RIC to work, the incident commander should immediately assign 

another on-scene company to stand by as the RIC. At a minimum, the incident commander should 

request an additional alarm and designate a company or companies to function as RIC. The 

remainder of the companies should report to staging. If no units are available, the incident commander 

should assign at least two members to act as a rapid intervention team while awaiting a special-called 

RIC to arrive. An engine company may be designated as the RIC pending arrival of an additional 

ladder company or rescue company. This ensures compliance with OSHA’s “2 In/2 Out” rule under 29 

CFR 1910.134, Respiratory Protection [OSHA 1998]. 

Many fire departments have a defined response plan for the dispatch of an additional company (engine, 

truck, squad, rescue, and/or command officer) to respond to an incident and stand by as the RIC. Based 

upon the complexity, magnitude, configuration of the structure or geographical layout of the incident, 
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the incident commander may deploy additional RIC/Firefighter Assist and Search Team (FAST) by 

location or function [NFPA 2020a]. 

Upon arrival or upon appointment, the RIC officer should confer with the incident commander. The 

RIC officer should establish an area to stage the rapid intervention team and the necessary RIC 

equipment. The RIC equipment should include: 

• Tool staging tarp 

• Rescue SCBA (RIC Pack) 

• Forcible entry tools such as a Halligan bar or other pry tool 

• Stokes basket 

• 150-foot rope for search and rescue 

• Wire cutters

• Rebar cutter

• Saws 

• Thermal imager 

• Emergency strobe lights 

• Life-saving rope/life belt 

• Elevator keys for buildings with elevators [FDNY 2011; LAFD 2001; TSFRS 2014]. 

It is important to stage all necessary RIC equipment in an expedient manner. The RIC officer, 

accompanied by one member of the RIC/FAST, should perform an incident scene survey while the 

remaining RIC members assemble the RIC equipment. If the size of the structure does not allow for a 

360-degree survey of the building, this fact should be relayed to the incident commander as soon as 

possible. This should be a benchmark for Command to designate another RIC/FAST to effectively 

cover all sides of the building. 

During this survey, the RIC officer and members should look for ways in and out of the structure, 

including window configuration, fire escapes, and construction features. The RIC officer should note 

the feasibility for placement of ground ladders for rescue or escape purposes. The RIC officer should 

be responsible for setting up and securing a suitable secondary egress for interior crews. This may 

include laddering multiple sides of the structure. Once the RIC has determined the need for an egress 

ladder, the window glass should be removed. This should only be done after conferring with Command 

that the removal of the window will not affect firefighting operations. Once approved by Command, 

the egress ladder should be placed at the window. The location of the egress ladder(s) should be 

announced over the radio by the RIC officer [Toledo Fire & Rescue Department 2012].

After the above tasks are completed, the RIC officer should inform Command that a 360-degree survey 

is complete and the RIC is ready to intervene, if necessary. Once the incident scene survey has been 

completed and the RIC equipment is in place, the entire RIC should be in an area immediately 

accessible to the building for rapid deployment plus maintaining radio contact with Command. The 

RIC officer should brief all members of the RIC as to the results of his/her incident scene survey. The 

RIC should operate as one unit. Additional crews may be added to or in support of the team as 

necessary. When more than one company is added as part of the rapid intervention team, a rescue 

group should be formed with a rescue group supervisor [Toledo Fire & Rescue Department 2012]. 

Another consideration for Command is to request the response of an advanced life support (ALS) 
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engine company or truck company as a component of the RIC Group. The members of the advance life 

support company are trained to operate in an IDLH atmosphere and can function as part of the RIC, 

plus they can provide advanced life support to affected firefighters [FDNY 2011]. 

The RIC officer and RIC members will coordinate with Command to formulate rescue plan 

contingencies and continue to monitor the radio and fireground conditions. RIC protection is not a 

passive assignment. This is a process of ongoing information gathering and diligent scene monitoring 

until the unit is released by the incident commander. The RIC function is a critical component for 

firefighter safety. 

To ensure that firefighters and fire officers are properly trained to conduct RIC operations, they should 

meet the requirements of NFPA 1407, Standard for Training Fire Service Rapid Intervention Crews 

[NFPA 2020a]. NFPA 1407 provides rapid intervention techniques and maneuvers pus necessitates a 

vast knowledge of tools and equipment and their applications. A well-trained and well-equipped RIC 

with just the basics in equipment is a safety net at structural fires, but the crew must be knowledgeable 

in technical rescue skills as well. The training programs should cover risk assessment, deployment, and 

activation of RICs, radio communications procedures, the integration of firefighter Maydays and their 

rescues into departmental incident management system, and full and operable personnel accountability 

system. [NFPA 2020a].

Recommendation #11: Fire departments should ensure that their radio communication system can 

provide adequate coverage based on the demands of an incident and complies with NFPA 1561, 

Standard on Emergency Services Incident Management System and Command Safety and NFPA 

1221, Standard for the Installation, Maintenance, and Use of Emergency Services Communications 

Systems. 

Discussion: Note: Although there is no evidence that the following recommendation would have 

prevented this fatality, it is being provided as a reminder of effective radio communication operations. 

At this incident, the county dispatch dispatched on the VHF frequency. The county is divided into 

County Fire North and County Fire South dispatch frequencies. The state fire channel is used for a 

tactical channel for working incidents. The state fire channel is a non-repeater channel and is not 

recorded. 

NFPA 1221, Standard for the Installation, Maintenance, and Use of Emergency Services 

Communications Systems, supports the National Incident Management System (NIMS) requirements 

for interoperability; reliability, scalability, and portability; and resilience and redundancy among 

communications systems. The standard establishes a benchmark for communication equipment 

installation, maintenance, and testing/use, which are critical to ensure that communications remain in 

place for emergency management/response personnel and to mitigate the chance of disruptions during 

an incident. NFPA 1221 supports the components of an interoperability plan by requiring that 

emergency services organizations develop policies and SOPs/SOGs for use of communications 

equipment. The standard ensures that communications equipment is properly functioning. Practicing 

preventive maintenance, as called for in the standard, helps emergency management/response 

organizations avoid high replacement costs for communications equipment [NFPA 2019]. 
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Effective fireground radio communication is an important tool to ensure proper command and control 

of an incident plus firefighter safety and health. The radio system must be dependable, consistent, and 

functional to ensure that effective communications are maintained, especially during emergency 

incidents. Fire departments should have a Communications SOP/SOG that outlines the communication 

procedures for fireground operations. Fire departments should ensure that the department’s 

communications division and communication center and/dispatch center are part of this process. 

Another important aspect of this process is an effective education and training program for all 

members of the department. 

Radio frequency usually refers to the radio frequency of the assigned channel. A radio channel is 

defined as the width of the channel depending on the type of transmissions and the tolerance for the 

frequency of emission. A radio channel is normally allocated for radio transmission in a specified type 

of service or by a specified transmitter. Fire departments should ensure that an adequate number of 

radio channels are available. Multiple radio channels are necessary at large-scale or complex incidents, 

such as a commercial structure fire, mass-casualty incident, hazardous materials incident, or special 

operations incident [FIRESCOPE 2017; NFPA 2020b]. 

NFPA 1561 Standard on Emergency Services Incident Management System and Command Safety, 

Paragraph 6.1.2, requires, “The communications system shall have the capacity to provide one dispatch 

radio channel and a separate tactical radio channel for initial use at the incident.” Paragraph 6.1.3 

states, “When a division or group has been implemented, the communications system shall have the 

capacity to provide a dispatch radio channel, a command radio channel, and a tactical radio channel.” 

Fire departments should preplan for not only large-scale or complex incidents, but also for the ability 

to handle daily operations. SOPs/SOGs, radio equipment (e.g., mobile radios, portable radios), other 

hardware (e.g., mobile data terminals, laptop computers, CAD system), and dispatch and 

communications protocols should be in place to ensure that these additional channels are available 

when needed [NFPA 2020b]. 

Every firefighter and company officer should take responsibility to ensure radios are properly used. 

Firefighters must have their portable radio and have the portable radio turned on and on the correct 

channel. A company officer must ensure that all members of the crew comply with these requirements. 

Portable radios should be designed and positioned to allow a firefighter to monitor and transmit a clear 

message [IAFF 2010;].

A fire department should provide the necessary number of radio channels relating to complex or largescale incidents needing multiple tactical channels. NFPA 1561 Standard on Emergency Services 

Incident Management System and Command Safety states in Paragraph 6.1.4, “The communications 

system shall provide reserve capacity for complex or multiple incidents.” This would require fire 

departments to preplan radio channel usage for all incident levels based upon the needs of an 

emergency incident including large-scale or complex incidents [NFPA 2020b]. 

When a fire department responds to an incident, incident commanders should forecast for the incident 

to determine if there is potential for it being a complex or long-term operation that may require 

additional resources, including demands on the communications system. As incidents increase in size, 
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the communication system must keep up with the demands of the incident. The incident commander 

must be able to communicate with company officers and division/group supervisors [FIRESCOPE 

2015]. Before communications become an issue, the incident commander must consider options for 

alleviating excessive radio traffic. Several options are: 

• Assign non-fireground resources (e.g., Staging, Rehab) to a separate tactical channel or talkgroup channel 

• Designate a command channel, which is a radio channel designated by the fire department to 

provide for communications between the incident commander and the division/group 

supervisors or branch directors during an emergency incident 

• For incidents involving large geographical areas, designate a tactical channel or talk-group for 

each division [NFPA 2020b]. 

NFPA 1561, Paragraph 6.2.2 states, “Clear text/plain language shall be used for radio 

communications.” The intent of the use of clear text/plain language for radio communications is to 

reduce confusion at incidents, particularly where different agencies work together [NFPA 2020b]. 

Recommendation #12: States should ensure anyone (including homeowners) using power tools or 

other digging equipment that will penetrate the ground call “811 or 811 Dig Safe” three business 

days (72 hours) prior to digging to identify if any buried utilities are present and mark their 

location(s). 

Discussion: Prior to this incident, four bollards were installed at the office building on September 10, 

2019, on Side Bravo in the parking lot to protect the heat pumps next to the building. The contractor 

that installed the bollards did not contact “811 Dig Safe” prior to digging the holes for the bollards. 

811 is the national call-before-you-dig phone number. Anyone who plans to dig should call 811 or go 

to their state 811 center’s website at least three business days before digging to request that the 

approximate location of buried utilities be marked with paint or flags to avoid unintentionally digging

into an underground utility line [CGA 2021]. Hitting a buried line while digging can disrupt utility 

service, cost money to repair, and cause serious injury or death. 

“811 DigSafe” operates in the states of Maine, Vermont, Rhode Island, New Hampshire, and the 

Commonwealth of Massachusetts. The Public Utilities Commission is the agency that oversees the 

“811 DigSafe” program in Maine. Utility locators will show the approximate horizontal location in 

advance of any type of digging or excavation by locating and marking underground facilities. This 

information helps anyone digging or excavating around underground facilities stay safe. Maine state 

code clearly provides for marking for all underground utilities. Communications with “811 DigSafe” is 

necessary to provide the mapping of underground utilities to prevent accidents from occurring [811 

Dig safe 2020]. 

“811 DigSafe” offers an Excavator Manual, A Guide to Safe Excavation Practices in Massachusetts, 

Maine, New Hampshire, Rhode Island, and Vermont. [DigSafe 2020] The purpose of this document is 

to provide anyone who is going to conduct any type of excavation with a basic understanding of the 
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responsibilities of each state concerning safe excavation practices and the protection of underground 

facilities.

Recommendation #13: Local and state enforcement agencies should ensure that a leak test of the 

piping system is conducted in accordance with the requirements of NFPA 54, National Fuel Gas 

Code, and NFPA 58, Liquefied Petroleum Gas Code, whenever propane service is initiated or 

restored.

Discussion: At this incident, when the propane tank was refilled and returned to service, a leak test of 

the piping system was never performed, which was required by NFPA 54, National Fuel Gas Code and 

NFPA 58, Liquefied Petroleum Gas Code. 

NFPA 54, National Fuel Gas Code, covers the appliances and piping downstream of the second-stage 

regulator, while NFPA 58, Liquefied Petroleum Gas Code, covers the propane tank and piping up to 

the second-stage regulator. Both codes require that the piping system shall be checked for leakage

immediately after the gas is turned on into a new system or into a system that has been initially 

restored after an interruption of service. [NFPA 2018a; NFPA 2017a]. 

When there is propane in a tank, there is constant pressure in the system. When the amount of fuel 

goes down, so does the pressure. Loss of pressure can cause leaks because of the expansion and 

retraction of the piping compound in the propane system. Whenever there is an interruption in service, 

such as running out of propane, a leak test will reveal any leaks in the piping. A leak test reveals any 

leaks that may have formed during the shutdown period. 

Leak testing should be performed by a certified technician. 

NFPA 54, Annex C, and NFPA 58, Annex L, suggest methods for checking for leaks [NFPA 2018a, 

NFPA 2017a]. 

NFPA 54, Annex D, provides guidelines for emergency procedures where an investigation discloses a 

concentration of gas inside a building [NFPA 2018a]. 

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Virginia Beach VA; Virginia Beach Fire Department.

Investigator Information

This incident was investigated by Murrey E. Loflin, Investigator; Stephen T. Miles, Safety and 

Occupational Health Specialist; and Jeffery Funke, Lead Occupational Health Manager with the

NIOSH Fire Fighter Fatality Investigation and Prevention Program, Surveillance and Field 

Investigations Branch, Division of Safety Research located in Morgantown, WV. An expert technical 

review was provided by Master Fire Fighter Mark Hundley, Hazardous Materials Specialist with the 

Virginia Beach Fire Department and Captain Kevin Okonski, Hazardous Material Technician with the 

Houston Fire Department. A technical review was also provided by the National Fire Protection 

Association, Public Fire Protection Division. 

Disclaimer 

Mention of any company or product does not constitute endorsement by the National Institute for 

Occupational Safety and Health, Centers for Disease Control and Prevention. In addition, citations to 

websites external to NIOSH do not constitute NIOSH endorsement of the sponsoring organizations or 

their programs or products. Furthermore, NIOSH is not responsible for the content of these websites. 

All web addresses referenced in this document were accessible as of the publication date.

 
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Report # F2019-16

Appendix One

Site Safety and Control Plan

ICS 208 HM 
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Office Building–Maine

Report # F2019-16
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Captain Killed and Six Firefighters Injured at a Propane Explosion in an 

Office Building–Maine

Report # F2019-16

Appendix Two

Example Safety Data Sheet – Propane
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Report # F2019-16
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Office Building–Maine

Report # F2019-16
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Office Building–Maine

Report # F2019-16
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Captain Killed and Six Firefighters Injured at a Propane Explosion in an 

Office Building–Maine

Report # F2019-16
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Captain Killed and Six Firefighters Injured at a Propane Explosion in an 

Office Building–Maine

Report # F2019-16
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Captain Killed and Six Firefighters Injured at a Propane Explosion in an 

Office Building–Maine

Report # F2019-16
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Captain Killed and Six Firefighters Injured at a Propane Explosion in an 

Office Building–Maine

Report # F2019-16
Page 67

Captain Killed and Six Firefighters Injured at a Propane Explosion in an 

Office Building–Maine

Report # F2019-16
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Captain Killed and Six Firefighters Injured at a Propane Explosion in an 

Office Building–Maine

Report # F2019-16
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Captain Killed and Six Firefighters Injured at a Propane Explosion in an 

Office Building–Maine

Report # F2019-16
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Captain Killed and Six Firefighters Injured at a Propane Explosion in an 

Office Building–Maine

Report # F2019-16
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Captain Killed and Six Firefighters Injured at a Propane Explosion in an 

Office Building–Maine

Report # F2019-16

Appendix Three

Atmospheric Monitoring Investigation Checklist