One Firefighter Dies and Another Injured in Natural Gas Line 

Explosion— Wisconsin 

Page i

2018-12 • 7/1/2021

Executive Summary

On July 10, 2018, a 34-year old paid-oncall/volunteer fire Captain died, and another 

firefighter was injured in a building 

explosion while responding to a report of a 

natural gas leak. At 1820 hours the local 

combination fire department was dispatched 

for a report of gas odor at an intersection 

approximately 1 block away from the fire 

station. The initial arriving crew 

immediately began evacuating the 

surrounding buildings. Meeting resistance 

from civilians who were unwilling to 

evacuate businesses in the area, the Incident 

Commander called for additional personnel 

to respond to the station. A Captain with the 

fire department arrived following the 

staffing request, along with several other 

firefighters. After checking in with the 

Incident Commander, the Captain, along 

with firefighters from the initial responding 

crew, entered a building near the suspected leak to control utilities in the basement. As the crew was 

exiting, the building exploded. One firefighter walked away from the blast with minor injuries. 

Firefighters on-scene searched for the Captain and the other firefighter in the pile of rubble from the 

building. The injured firefighter was found buried up to his face, conscious and moving. He was 

transported to the hospital in critical condition having sustained multiple fractures to his jaw and head. 

The Captain was found face down in the rubble. Crews worked to extract the Captain, loaded him into 

a waiting Advanced Life Support (ALS) staffed ambulance, and performed cardiopulmonary 

resuscitation until they reached the hospital where he later passed away from his injuries. 

Site of Natural Gas Explosion

(Fire Department Photo) 
Page iii

One Fire Fighter Dies and Another Injured in Natural Gas Line Explosion—

Wisconsin

Report # F2018-12

Contributing Factors

• Sub-contractor performing unpermitted directional boring for underground utility 

• Natural gas leak caused by directional boring 

• Natural gas line explosion 

• Responders working in blast radius to evacuate civilians lingering in the area

• Captain and crew entered building previously evacuated during primary search to attempt to 

control utilities

Key Recommendations

• Fire departments should refer to the 2020 Emergency Response Guidebook [USDOT 2020] 

and operate outside of the hot zone once civilians are evacuated

• Fire departments should ensure that Incident Commanders continuously evaluate the risk 

versus gain when making operational decisions during evacuation operations. 

• Fire departments should ensure that firefighters are trained in situational awareness, personal 

safety, and accountability. 

• Fire Departments should ensure that their members (and specifically their hazardous materials 

teams) are provided and trained in the latest tactics and equipment for detecting and 

responding to hazardous materials situations, including gas leaks.

Additionally, governing municipalities (federal, state, regional, and local) should: 

Work with civilians to educate them on the hazards of gas leaks and the need to immediately 

evacuate when public safety workers (fire and police) direct them to do so

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 reports 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 Web site at www.cdc.gov/niosh/fire or call toll free 1-800-CDC-INFO (1-800-232-4636).
Page 1 

One Fire Fighter Dies and Another Injured in Natural Gas Line Explosion—

Wisconsin

Report # F2018-12

Introduction

On July 10, 2018, a 34-year old paid-on-call/volunteer Captain died and another firefighter was injured 

in a building explosion while responding to a report of an outside odor of natural gas. The Captain had 

arrived on-scene in response to a second call-back for additional resources following the need for a 

rapid evacuation spanning several blocks. The Captain and a crew of two firefighters went to control 

utilities in the basement of a building that had undergone a primary search and evacuation. As the crew 

was leaving the building, an unknown ignition source caused an explosion of the building, partially 

burying the Captain and one firefighter in the rubble. The buried firefighter was located, removed from 

a debris pile, and taken by EMS to a local hospital with significant injuries. The Captain was located 

with a pulse, which was lost upon loading him into an awaiting ambulance. Crews transported the 

Captain to a local hospital where he was later pronounced deceased. The third firefighter from the crew 

sustained minor injuries and was treated and released. The Chief remained on-scene until the Captain 

was transported, and he was treated at the hospital for a concussion sustained from falling debris down 

the street from the blast.

On July 29, 2018, a Safety Engineer and two Safety and Occupational Health Specialists from the 

NIOSH Fire Fighter Fatality Investigation and Prevention Program traveled to Wisconsin to investigate 

the incident. Photographs of the incident scene post clean-up were taken (See Photos 1 and 2). NIOSH 

investigators met with representatives from the City Police Department, City Building Officials, and 

Officers from the Fire Department. Interviews were conducted with fire department personnel who 

responded to the incident, as well as emergency medical personnel and the medical examiner assigned 

to the case. NIOSH investigators reviewed the department’s standard operating procedures (SOPs), the 

victim’s training records, and police photographs of the scene. NIOSH investigators were accompanied 

by the Chief, Fire Marshall, and Building Official to inspect the incident scene.
Page 2

One Fire Fighter Dies and Another Injured in Natural Gas Line Explosion—

Wisconsin

Report # F2018-12

Photo 1. Side Alpha of Pub prior to explosion.

(Photo from Google Maps)

Photo 2. Site of explosion. Note the building/origin of the explosion was destroyed during the 

blast

(NIOSH Photo)
Page 3 

One Fire Fighter Dies and Another Injured in Natural Gas Line Explosion—

Wisconsin

Report # F2018-12

Fire Department 

The combination department involved in this incident has two fire stations serving a primary 

geographical response area of 94 square miles and responds to approximately 1700 emergency 

incidents per year. A total of 45 volunteer members, 13 career firefighters, and 6 part-time firefighters 

serve a population of about 43,000 residents. 

The department owned the following apparatus at the time of the incident: 

• 2001 Engine 1 pumper 

• 2013 Engine 3 with 776-gallon water capacity and 1500 GPM pumping capacity

• 2007 Engine 8 

• 2017 E-One Typhoon 

• 2007 Ladder 2 

• 1999 Squad 5 

• 1999 Brush Truck 

• 1992 Brush Truck 

• 1997 Tender 

• 2017 Ladder 1 

• 2016 SUV

• 2017 SUV

• 2006 SUV

Among many other topics, the department’s extensive Standard Operating Procedures included 

sections on Radio Communications, National Incident Management System/Incident Command 

System (NIMS/ICS), Gas Meters, Incident Response, Mayday, Structure Fire Procedures, and 

Training. 

Training and Experience

To become a volunteer member, applicants submit a written application and photocopy of their 

personal identification. Applicants spend 2 nights at the fire department as an observer watching drills. 

Following a background check, applicants are required to get medical clearance via a physical, as well 

as pass a physical agility test. Mandatory training within the first year includes Bloodborne Pathogen 

training, Basic Life Support CPR for the healthcare provider, NIMS/ICS Series Courses (100, 200, 300 

and 400), and training on radio operations. 

Probationary members are assigned a mentor for a minimum of 1 year. The state of Wisconsin requires 

60 hours of entry level training. After entry level training, probationary members obtain SCBA 

training. Members must obtain state certification as Fire Fighter I and advance to Fire Fighter II before 

the individual can go interior or be “on-air” at a fire incident. These courses meet NFPA 1001 Standard 

for Fire Fighter Professional Qualifications. All firefighters with this department are at least Fire 

Fighter I certified [NFPA 2019]. 
Page 4 

One Fire Fighter Dies and Another Injured in Natural Gas Line Explosion—

Wisconsin

Report # F2018-12

Firefighter/Rank Years of 

Experience

Training/Certification

Chief 30 years Entry Level Firefighter, Firefighter I, Firefighter II, 

Driver Operator Pumper, Fire Inspector, Fire 

Instructor, Fire Instructor EXP, Safety Officer, Fire 

Officer I, Fire Officer II, NIMS 100, 200, 300, 400, 

700, and 800, HAZMAT Operations, Chief Fire 

Officer Certified

Bachelor’s Degree in Fire Science, NFPA 1670 

Technical Rescue Technician

Assistant Chief/Incident 

Commander 

45 years Entry Level Firefighter, Firefighter I, Firefighter II, 

Fire Inspector, Safety Officer, NIMS 100, 200, 300, 

400, 700, and 800, HAZMAT Operations

Captain (deceased) 15 years Entry Level Firefighter, Firefighter I, Firefighter II, 

Driver Operator-Pumper, Driver Operator-Aerial, 

Fire Instructor, Safety Officer, Fire Officer 1, NIMS 

100, 200, 300, 400, 700, and 800, HAZMAT 

Operations 

Fire Fighter 1 (injured) 5 years Entry Level Firefighter, Firefighter I,Firefighter II, 

Driver Operator-Pumper, Fire Inspector, NIMS 100, 

ICS 700, HAZMAT Operations

Fire Fighter 2 (minor 

injuries)

10 months Firefighter I, NIMS 100 &200, ICS 700 & 800

Equipment and Personnel 

The fire department responded with one engine (Engine 3) staffed with 5 firefighters and one 

command vehicle (Car 2) staffed by an Assistant Chief.

While the initial responding crew began evacuating the buildings in the area surrounding the gas leak, 

the Assistant Chief/Incident Commander requested a call back for any available firefighters to respond 

to the station. Ladder 1 responded once a crew assembled at the fire department after the explosion. 

While this crew was assembling, the Captain grabbed his gear and walked from the firehouse to the 

intersection where the gas leak was occurring. 
Page 5 

One Fire Fighter Dies and Another Injured in Natural Gas Line Explosion—

Wisconsin

Report # F2018-12

The fire department is located approximately 2 blocks northeast of the site of the gas leak/explosion. 

Several firefighters responded to the scene on foot due to the proximity. The apparatus was initially 

parked within steps of the leak, then rapidly moved back when the location of the gas leak was 

established. 

Structure/Blast Area

The initial report of gas odor came from a pizza parlor at the intersection of two city roads, 

approximately 1 block down from where underground boring was taking place. The pizza parlor was 

directly across the street from the building that exploded. The area is a main street in a historic city, 

consisting of older, multi-story brick buildings (ordinary type 3 structures) which housed restaurants 

and businesses on the first floor, and many with apartments or additional business offices on the upper 

floors. To the northwest side of the intersection, there was a bar/pub (explosion site). Across the street

from the explosion site to the east is a multipurpose building that houses a confection restaurant and 

apartments. To the southeast of the intersection where the explosion occurred is a building shared by 

the Department of Corrections and a Mexican restaurant. To the west on the other side of the street was 

the pizza parlor. Given the time of day, the restaurants in the area were full of patrons during the 

“dinner rush.”

The building that exploded was a 2-story brick structure built in 1883. The building was 4,222 sq. ft 

above grade with a 2,257 sq. ft footprint including porches, entries, and garages. The building also had 

a below grade cellar with access directly inside the side Delta entryway.

The explosion occurred during business hours. Prior to evacuation, there were approximately 40 

civilians inside of the structure

Personal Protective Equipment 

The Detective Sergeant investigating the incident reported to the NIOSH investigators that the Captain 

(victim) was wearing his issued structural firefighting coat, pants, boots, and helmet when he was 

found at the scene of the incident. Both the Captain and injured firefighter were wearing an SCBA at 

the time of the explosion, but neither were “on air” during the response/explosion. NIOSH 

investigators examined and photographed all available structural firefighting clothing being held at the 

city evidence department under custody of the Police. The PPE were not determined to be a 

contributing factor in this incident

Weather

At the time of the report of gas odor in the area, the temperature was around 74 degrees and sunny with 

a 4-mph breeze from the north. Weather does not appear to be a contributing factor in this incident 

[Weather Underground, 2018]. 
Page 6 

One Fire Fighter Dies and Another Injured in Natural Gas Line Explosion—

Wisconsin

Report # F2018-12

Directional Boring

A 5-inch gas main was punctured by a sub-contractor during unpermitted underground boring to locate 

underground utilities, causing natural gas to collect in the sewers and basements of the surrounding 

buildings. An unknown ignition source caused the trapped gas to ignite and explode in the building 

while the firefighters were exiting.

Timeline

This timeline is provided to set out, to the extent possible, the sequence of events according to the 

recorded radio transmissions. Times are approximate and were obtained from review of the dispatch 

records, witness interviews, and other available information. Times have been rounded to the nearest 

minute. This timeline is not intended, nor should it be used, as a formal record of events. 

1820 hours

Gas line hit. Gas leak reported at a pizza parlor at the main intersection in the downtown area. 

1821 hours

Fire department dispatched. 

1822 hours

Engine 3 with 5 firefighters and Car 2 with an Assistant Chief arrived on-scene. The Assistant Chief 

established incident command on the east side of the scene. Firefighters noticed a heavy odor of gas in 

the area and immediately got readings of 6-7% of lower explosive level (LEL) on gas monitors as they 

exited the fire apparatus.

The driver of Engine 3 moved the apparatus east, away from the intersection. The rest of the crew 

broke into 2 teams and immediately began to evacuate civilians from businesses and apartments. The 

Incident Commander requested a staffing call-back for any available firefighters to respond

1824 hours

IC called the gas company who gave him a 30 minute estimated time of arrival (ETA) for the response 

crew.

Police were requested to assist with traffic control.

Fire crews continued to evacuate civilians and check gas levels in the surrounding building, noting 

high readings coming from the sewers along the streets. Crews reported being able to hear hissing out 

of the sewer grates.

 
Page 7

One Fire Fighter Dies and Another Injured in Natural Gas Line Explosion—

Wisconsin

Report # F2018-12

1835 hours

The Fire Chief arrived on-scene. Command remained with the Assistant Chief. The Fire Chief 

switched up crews, putting one experienced firefighter with each newer firefighter (3 teams of 2) and 

they continued evacuating buildings. The Chief met with the Detective Sergeant on scene and had him 

move a perimeter 5 blocks out and moved Command back to the firehouse

1845 hours

The Captain arrived at the fire department, grabbed his gear, pulled a gas meter from Truck 2, and 

walked down to the intersection. The Captain teamed up with a 2-man crew from Engine 3 to control 

utilities in the basement of a building consisting of a bar on the first floor with apartments above. 

1905 hours

A power utility company representative arrived on-scene as the Captain and 2 firefighters were exiting 

the building.

The building exploded, and structure fires ignited. 

Gas leak continued.

1906 hours

Assistant Chief/Incident Commander called for a personnel accountability report (PAR).

A firefighter who rushed to the pile of rubble radioed the Chief that he saw a firefighter buried in the 

rubble. A second firefighter who came to the call back helped uncover the buried firefighter, then 

helped him to his feet and moved him about 1 block north away from the pile towards the fire 

department. The second firefighter met with a third firefighter from the basement crew and transferred 

patient care to him. The second firefighter returned to the pile. 

MABAS box alarm was called for structure fire. (Fire and EMS mutual aid) 

1912 hours

The Advanced Life Support EMS crew on-scene took over care of the injured firefighter and 

transported him to the hospital with serious injuries.
Page 8

One Fire Fighter Dies and Another Injured in Natural Gas Line Explosion—

Wisconsin

Report # F2018-12

Firefighters continued arriving on scene and began digging through the pile searching for the Captain. 

An Assistant Chief who took over operations on the pile told crews to drop their SCBA to expedite the 

search.

Two fire fighters moved from the pile to drop their SCBA and spotted the Captain face down in the 

rubble near the edge of the pile. One of the firefighters felt a carotid pulse prior to the crew securing 

the Captain to a backboard and moving him to a waiting ambulance. The pulse was lost before the 

ambulance was in-route to the hospital and the ALS crew began cardiac arrest protocol.

Unified Command established. 

1927 hours 

1 block radius evacuation completed. 2 block radius evacuation initiated. 

1951 hours

Evacuation area expanded to 5-block radius. 

2005 hours

The Captain was pronounced deceased at the hospital

2042 hours

Evacuation area expanded to 1⁄2 mile radius. 

2135 hours

5th MABAS box alarm called. 

0245 hours

Gas shut off. All clear issued for firefighters to work hand lines at the explosion site/city road 

intersection. Utility company continued to purge additional gas lines. 

0621 hours

All first due Fire Department personnel fully withdrawn from the response
Page 9 

One Fire Fighter Dies and Another Injured in Natural Gas Line Explosion—

Wisconsin

Report # F2018-12

Investigation

On July 10, 2018, a 34-year old paid, on-call Captain died and another firefighter was injured in a 

building explosion while responding to a report of a natural gas leak. The deceased Captain was 

responding to a call-back to re-staff the fire station during a gas leak response. At 1821 hours, dispatch 

was notified of a possible gas leak at the intersection of 2 city roads approximately 2 blocks from the 

fire station. At 1825 hours, Engine 3 responded with 5 firefighters, along with Car 2 driven by the 

Assistant Chief on shift at that time.

The initial report of gas odor came from a pizza parlor at the intersection of two city roads 

approximately 1 block down from where underground boring was taking place. The area is a main 

street in a historic city, consisting of older, multi-story brick buildings which housed restaurants and 

businesses on the first floor, and many with apartments or additional business offices on the upper 

floors. To the northwest side of the intersection, there was a bar/pub (explosion site). Across the street 

to the east is a multipurpose building that houses a confection restaurant and apartments. To the 

southeast of the intersection is a building shared by the Department of Corrections and a Mexican 

restaurant. To the west on the other side of the street was the pizza parlor (see Diagram). Given the 

time of day, the restaurants in the area were full of patrons during the “dinner rush.” 

Diagram. Overview of intersection where explosion occurred. Depicts site of explosion, area 

where boring line pierced gas main, and the direction of the boring line
Page 10

One Fire Fighter Dies and Another Injured in Natural Gas Line Explosion—

Wisconsin

Report # F2018-12

Upon arrival, firefighters noticed a heavy odor of natural gas in the area. The Assistant Chief 

established incident command towards the east side of the scene. When getting off the engine, 

firefighters reported gas meter readings of 6-7% LEL. The driver of Engine 3 moved the apparatus east 

from the intersection and the suspected source of the leak. The rest of the crew divided into 2 crews 

and immediately began evacuating civilians from the businesses and apartments surrounding the 

intersection. Crews reported elevated gas readings in all the buildings in a two-block radius of the 

intersection.

At 1825 hours over the radio, the Assistant Chief requested a staffing call-back for any available 

firefighters to respond. The Assistant Chief/IC then called the gas company and was given a 30-minute 

estimated time of arrival for a gas utility crew to respond. At this time, city police officers were onscene providing traffic control and helping keep civilians out of the area. The first responding fire 

crews continued to evacuate civilians and check gas levels in the buildings, noting high readings 

coming from the sewers along the streets. Crews reported that they were able to hear hissing out of the 

sewer grates.

At approximately 1835 hours, the Fire Chief arrived on scene and made adjustments to the evacuation 

crews in order to keep one experienced firefighter with each lesser experienced firefighter. After a 

brief discussion with a police department Sergeant, the decision was made to expand the evacuation 

area and continue evacuating civilians from all buildings. Evacuations were difficult due to civilians 

lingering in dining establishments and refusing to evacuate. Crews also encountered multiple 

individuals walking into the hot zone via side streets and alleyways. This forced crews to remain in 

the hot zone longer. The fire department in this incident effectively evacuated the buildings within the 

hot zone, preventing more casualties that could have resulted from the blast.

At approximately 1845 hours, the Captain arrived at the fire department. One firefighter was preparing 

to bring a ladder truck down to the scene. The Captain had a brief conversation with him, then grabbed 

a gas meter and walked to the scene on foot. When the Captain arrived on scene, he checked in with 

the Assistant Chief/IC and discussed going back into one of the previously evacuated buildings in 

which he was a commercial tenant, to control utilities in the basement. The Captain stated he was 

familiar with the utilities in the structure. Along with two other firefighters, he re-entered and went to 

the basement. They discussed shutting off the power in the building, and the Captain expressed 

concern that the gas meter was alarming at 100%. The crew decided to exit the structure. One 

firefighter headed around the back of the building’s exterior to look for a gas shut off valve. As the 

Captain and the other firefighter were stepping out of the threshold on Side Delta, the building 

exploded (approximately 1905 hours). 

The Chief, who was approximately 1 block down from the blast, immediately called for a PAR. He 

suffered a concussion and mild hearing loss following the blast. Another firefighter, who was standing 

on the sidewalk up from the building when the explosion occurred, turned to the pile of burning rubble 

and saw the firefighter (who was with the Captain in the basement) partially buried. At approximately 

1906 hours, he radioed to the Chief that there was a firefighter down. The injured firefighter slowly sat 

up and was assisted away from the pile. The injured firefighter was medically evaluated by a third 
Page 11 

One Fire Fighter Dies and Another Injured in Natural Gas Line Explosion—

Wisconsin

Report # F2018-12

firefighter who had also been in the basement with the Captain. Patient care was then transferred to the 

first arriving EMS ALS crew.

At this time, other firefighters began searching the pile of rubble for the missing Captain. Engine 3 

began flowing water on what was left of the building, which was becoming more involved in fire. 

Engine 3 utilized a deck gun to put water on the fire. As the search continued, an Assistant Chief who 

had responded to the station call-back, and was operating on the pile, instructed the crews to remove 

their Self-Contained Breathing Apparatus (SCBA) because it was slowing down the search operation. 

The firefighter who had found the first downed firefighter and the firefighter who was part of the 

Captain’s basement crew went to drop their SCBA when they saw the reflective trim of the Captain’s 

boot in the rubble. The Captain was found lying face down, with his right boot and head visible in the 

debris. The rest of his body was covered in rubble. 

A firefighter reported feeling a faint carotid pulse on the Captain as they were removing him from the 

pile. The Captain was loaded onto a backboard and transferred to a waiting ALS crew. No pulse was 

detected in the ambulance and the crew immediately began resuscitative efforts. The Captain was 

pronounced dead at the hospital at 2005 hours. 

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:

• Sub-contractor performing unpermitted directional boring for underground utility 

• Natural gas leak caused by directional boring 

• Natural gas line explosion

• Responders working to evacuate lingering civilians within blast radius at time of explosion 

• Captain and crew entered building previously evacuated during primary search to attempt to 

control utilities

Cause of Death

According to the Medical Examiner’s report, the Captain’s cause of death was multiple blunt impact 

injuries.
Page 12 

One Fire Fighter Dies and Another Injured in Natural Gas Line Explosion—

Wisconsin

Report # F2018-12

Recommendations

Recommendation #1: Fire departments should use the 2020 Emergency Response Guidebook and 

ensure that collapse/explosion control zones are established when dealing with a potential explosion 

hazard. 

Discussion: During operations dealing with a gas leak and the possibility of an explosion, apparatus 

should be positioned outside the hazard area (330 feet/100 meters per the fire department’s SOP and 

the Department of Transportation Emergency Response Guidebook [USDOT 2020]. Positioning 

should include a barrier, if possible, and water supply considerations. 

Once a building within the hazard area has been evacuated, firefighters should not re-enter until it has 

been cleared as safe to do so. All efforts to evacuate immediate hazard areas should be performed 

swiftly and efficiently to limit first responder exposure to potential explosions.

In this incident, the Captain and two firefighters re-entered a previously evacuated structure within the 

hot zone to turn off utilities in the building. The explosion occurred just as the decision was made to 

expand the already established hot zone, and as the Captain and firefighters were exiting the structure.

Recommendation #2: Fire departments should ensure that Incident Commanders continuously 

evaluate the risk versus gain when making operational decisions during evacuation operations.

Discussion: The initial size-up conducted by the first arriving officer allows the officer to assess the 

conditions and to assist in planning the response strategy. The following general factors are important 

considerations during a size-up: occupancy type involved, potential for civilians in the structure, 

hazardous conditions, exposures, and time considerations such as the time of the incident, length of 

time before arrival, and time elapsed [IFSTA, 2013]. The Incident Commander must perform a risk 

analysis to determine what hazards are present, what the risks to personnel are, how the risks can be 

eliminated or reduced, and the benefits to be gained from interior or offensive operations [Kipp and 

Loflin 1996]. The size-up must include continued assessment of risk versus gain during incident 

operations. According to NFPA 1500 A.8.3.3, “The acceptable level of risk is directly related to the 

potential to save lives or property. Where there is no potential to save lives, the risk to the fire 

department members must be evaluated in proportion to the ability to save property of value. When 

there is no ability to save lives or property, there is no justification to expose fire department members 

to any avoidable risk, and defensive fire suppression operations are the appropriate strategy” [NFPA 

2018a]. 

In this incident, the building that the Captain and 2 firefighters re-entered had already undergone a 

primary search and evacuation. The decision to expand the hot zone was made while the Captain and 

firefighters were exiting, and the building exploded. 

Recommendation #3: Fire departments should ensure that firefighters are trained in situational 

awareness, personal safety, and accountability. 
Page 13 

One Fire Fighter Dies and Another Injured in Natural Gas Line Explosion—

Wisconsin

Report # F2018-12

One of the most critical responsibilities firefighters face on an emergency scene is maintaining 

situational awareness. All firefighters operating at an incident should maintain situational awareness 

and conduct a continuous risk assessment throughout the incident. The opposite of situational 

awareness is tunnel vision where the firefighters become so focused on a task, firefighting, or other 

operational assignments that they fail to sense changes in their environment. Firefighters can maintain 

their situational awareness by training with and trusting their tools and detection instruments, 

communicating with fellow crew mates and command, and continuously looking, listening, and feeling 

around for new or unusual sounds or vibrations. 

Essentials of Fire Fighting and Fire Department Operations defines situational awareness as an 

awareness of the immediate surroundings. On an emergency scene, every firefighter should be trained 

to be constantly alert for changing and unsafe conditions, regardless of whether a safety officer has 

been designated for that incident [Essentials of Fire Fighting and Fire Department Operations 2008].

To assist with “go or no-go” decision making, the International Association of Fire Chiefs, Safety, 

Health and Survival section developed the “Rules of Engagement for Structural Fire Fighting.” While 

this incident was not initially a structure fire, the Rules can be applied to a variety of scenarios to assist 

both the firefighter and the Incident Commander in risk assessment. 

One principle applied in the Rules is that firefighters and the company officers are the members most 

at risk for injury or death and will be the first to identify unsafe conditions and practices. The Rules 

integrate the firefighter into the risk assessment decision making process. Where it is not safe to 

proceed, the rules allow a process for that decision to be made while still maintaining command unity 

and discipline [IAFC 2016]. 

In this incident, the IC and Fire Chief working with the Police supervisor continued to reevaluate 

conditions. Due to migrating natural gas in the 150-year-old infrastructure “Hot Zones” were difficult 

to establish due to elevated readings in multiple buildings. Additionally, police and fire crews having 

to deal with breaches from curious residents entering the area from alleyways and other locations that 

could not be controlled. Police perimeters were moved out three blocks from the initial response 

location. Command Location was moved five times during the operation. 

The Captain was assigned to utilities due to his knowledge of the buildings in the area which housed 

his restaurant/pub business. Although the building had previously been evacuated by the first 

responding crew, the Captain requested to re-enter the structure to control utilities as called for in the 

department’s SOPs. The IC utilized an accountability board upon arrival, and regained control of 

accountability post explosion. 

Recommendation #4: Fire Departments should ensure that their members (and specifically their 

hazardous materials teams) are provided and trained in the latest tactics and equipment for 

detecting and responding to hazardous materials situations, including gas leaks. 
Page 14 

One Fire Fighter Dies and Another Injured in Natural Gas Line Explosion—

Wisconsin

Report # F2018-12

Discussion: While gas meter training was not determined to be a contributing factor in this incident, it 

is an industry best practice to remain up to date on the latest technology, knowledge, and tactics when 

responding to highly technical emergencies. 

Regarding natural gas emergencies, firefighters must be thoroughly trained in the use of their 

combustible gas indicators and/or 4 gas meters. Training must include information on understanding

cross sensitivities, alarm points, proper sampling techniques, and limitations of the specific instrument. 

Fire departments often respond to natural gas leaks, and LEL monitors are an essential tool for helping 

establish whether it is safe to enter a structure when a natural leak is suspected. 

LEL monitors require maintenance (including frequent calibration) and proper training in their use to

be accurate and effective in the field. Manufacturer guidelines should be followed in maintaining and 

calibrating these technical devices. Understanding the proper use and reading requires routine training 

by qualified personnel. Inadequate training and maintenance will put firefighters at risk. 

New technologies emerge frequently, and it is up to the fire department to determine if they are 

applicable to their response area. For example, fire departments could consider using laser based 

natural gas detectors. This type of gas detector allows firefighters to greatly speed up their size-up and 

increases safety because it has a 100-foot range with sensitivity in the ppm range keeping them out of 

an Immediately Dangerous to Life and Health (IDLH) area. 

When conducting natural gas emergency training, the implementation of action levels built into the 

training SOP is important. Once a firefighter is proficient with use of the department’s chosen gas 

meter, training can then move on to what tactics they are supposed to implement based on the readings 

they obtain. This includes understanding how to interpret the data they are gathering and making 

responsive tactical decisions.

Recommendation #5: Cities and municipalities should work with civilians to educate them on the 

hazards of gas leaks and the need to immediately evacuate when public safety officials direct them 

to. 

Discussion: Time is of the essence when conducting an evacuation during a natural gas leak, or any 

hazardous situation. The occurrence of a natural gas leak is a low frequency event civilians encounter. 

This means that many may not understand the urgency to evacuate when there is no visible indication 

of danger, such as with a fire. It is crucial that public education programs are developed, tailored to, 

and distributed to residents of communities serviced by natural gas. 

Focus areas of such programs could include: 

• Identifying and reporting signs of a natural gas leak 

• What to do in the event of a gas leak

• How to prevent natural gas leaks from occurring in your home or business 
Page 15 

One Fire Fighter Dies and Another Injured in Natural Gas Line Explosion—

Wisconsin

Report # F2018-12

City officials play a critical role in emergency management. Preparing communities for a disaster or 

major emergency event takes careful planning and a thorough account of resources immediately 

available. By taking these things into consideration and developing protocols for mandatory 

compliance during an emergency, first responders will be able to conduct efficient operations that have 

the potential to save lives. The task of developing ordinances that communities are both aware of and 

responsible to uphold falls to the city officials and public health leaders in communities.

In this incident, the first responding crews from both the fire and police departments did an outstanding 

job conducting an efficient evacuation prior to the explosion. There is no doubt that dozens of lives 

were saved due to their efforts. It was reported that some crews were met with resistance when asking 

patrons to evacuate businesses in the hot zone. This resistance, along with individual civilians reentering the evacuation zone via back alleyways and side streets, forced the decision of Incident 

Command to remain in the hot zone until the all clear was given. City Emergency Managers and Fire 

Departments should take every opportunity to educate the public and encourage civilians to comply 

with directions from first responders. The quicker crews and civilians can get out of the immediately 

hazardous area, the less likely it will be that anyone is injured in the event of an explosion. 

NOTE: The following recommendations are not considered to be contributing factors for this 

incident, but they are good practices to include in fireground operations.

Recommendation #6: Fire departments should ensure an effective personnel accountability system 

is used to account for all firefighters and first responders assigned to any incident.

Discussion: Personnel accountability on a fireground means identifying and tracking all personnel 

working at the incident. A fire department should develop its own system and standardize it for all 

incidents. Accountability on the fire ground can be maintained by several methods: a passport system, 

a system using individual tags assigned to each firefighter, a riding list provided by the company 

officer, an SCBA tag system, or an incident command board [IFSTA 2013]. Some personal alert safety 

system (PASS) devices incorporated into SCBA can communicate automatically with a 

command/control module at the incident command post, establishing an automatic accountability 

system. NFPA 1500 and NFPA 1561 contain guidelines for the development of an accountability 

system for fireground and other emergency operations [NFPA 2014, 2018a]. 

As an incident escalates, additional staffing and resources will be needed, adding to the burden of 

tracking personnel accountability. At this point a tactical worksheet should be established with an 

assigned accountability officer or chief’s aide. In large incidents, this can also be used at the division 

level, with resources being assigned and tracked at the division level. 

An important aspect of a personnel accountability system is the personnel accountability report (PAR). 

A PAR is an organized on-scene roll call in which each supervisor reports the status of their crew when 

requested by the Incident Commander. The use of a personnel accountability system is recommended 

by NFPA 1500 Standard on Fire Department Occupational Safety and Health Program and NFPA 
Page 16

One Fire Fighter Dies and Another Injured in Natural Gas Line Explosion—

Wisconsin

Report # F2018-12

1561 Standard on Emergency Services Incident Management System. A functional personnel 

accountability system requires the following:

• development of a departmental SOP

• training all personnel

• strict enforcement during emergency incidents [NFPA 2014, 2018a]

The control of the personnel accountability system should be assigned to an individual responsible for 

maintaining the location and status of all assigned resources (resource status) at an incident. This is a 

separate role from the duties of the Incident Commander. The Incident Commander is responsible for 

overall command and control of the incident. Due to the importance of responder safety, this function 

would be assigned to a personnel accountability officer or resource status officer. This function can be 

staffed by the chief’s aide, staff assistant, field incident technician, chief officer, or other responder 

familiar with the department’s accountability system [NFPA 2014].

There are many different methods and tools for accounting resources. Some examples are as follows:

• command boards,

• tactical worksheets,

• apparatus riding lists,

• electronic bar-coding systems,

• accountability tags or keys (e.g. PASSPORT System) [NFPA 2014]

Different methods and tools for resource tracking and accountability can be used in conjunction with 

one another to facilitate the tracking of responders by both location and function. The components of 

the personnel accountability system should be modular and expand with the size and complexity of the 

incident [NFPA 2014].

With an accountability system in place, the Incident Commander may readily identify the location and 

time of all firefighters on the fireground. A properly initiated and enforced personnel accountability 

system that is consistently integrated into fireground command and control enhances firefighter safety 

and survival by helping to ensure a more timely and successful identification.

There has been much technological advancement in accountability systems. There are currently 

available PASS systems that have the capacity to act as a standard PASS device but also transmit a 

signal to the command console when the fire fighter has gone into alarm. Additionally, the Incident 

Commander can signal any and all fire fighters through their PASS device when there is a need to 

evacuate a structure.

In this incident, command initially set up an accountability system to which firefighters checked in at 

the command vehicle as they arrived on scene. Prior to the explosion, there was a functional 

accountability system in place with Incident Command, and the span of control was adequate. After 

the explosion occurred and rescue operations began, firefighters arrived on foot to the scene and 
Page 17 

One Fire Fighter Dies and Another Injured in Natural Gas Line Explosion—

Wisconsin

Report # F2018-12

headed straight for the pile. It was noted that it was unclear who all had responded until after the 

recovery was made. Once recovery was accomplished, accountability was regained, and command 

boards immediately came into play. Accountability is not considered a contributing factor to this 

fatality. However, when effective accountability is established early and maintained throughout the 

incident it can lead to an organized response. 

Recommendation 7: Fire departments should consider developing Flammable Gas Response SOPs 

jointly with utility experts and conduct annual joint training with utility companies to maintain 

familiarity with protocols. 

Discussion: When dealing with flammable gas emergencies (i.e. natural gas, propane gas), the 

responding fire department has the responsibility for protecting the emergency responders as well as 

civilians in cooperation with the local utilities. It is imperative that fire department procedures, 

training, and equipment all support this mission. Operational procedures that are standardized, clearly 

written, and mandated to each department member establish accountability, increase command, and 

improve effectiveness.

It is important to understand the difference between a policy and a procedure. A department policy is a 

guide to decision-making that originates with or is approved by top management in a fire department. 

Policies define the boundaries within which the administration expects department personnel to act in 

specified situations. A procedure is a written communication closely related to a policy. A procedure 

describes in writing the steps to be followed in carrying out organizational policies. SOPs are standard 

methods or rules in which an organization or a fire department operates to carry out a routine function. 

Usually these procedures are written in a policies and procedures handbook and all fire fighters should 

be well versed as to their content. [IFSTA 2013] 

When developing new SOPs or re-visiting established SOPs, consider including outside organizations 

who would also be involved in the response. In the case of a flammable gas leak, Fire Department

procedures should consider and mirror utility best practices for response and control, as these may very 

well be similar both tactically and strategically. By including local utility experts, the outcome will be 

a well-rounded SOP that clearly outlines the roles and responsibilities for firefighters and utility 

workers on the scene of a gas emergency. Fire department operational plans, trainings, strategies, and 

tactics should anticipate firefighters being on scene without utility assistance for extended periods of 

time and utilize utility professional guidance for how to proceed in these circumstances. 

As with any new or updated SOP, fire departments should conduct annual training to ensure fire 

fighters are familiar with the various responder roles outlined in the procedure. Utility technicians, fire 

department officers, and frontline firefighters should train on common techniques/procedures to ensure 

good on scene effectiveness and cooperation ensuring a unified effort. Training should be classroom 

based and hands-on using common/realistic natural gas emergency scenarios the fire department is 

expected to mitigate before utility assistance arrives.

In this incident, the fire department had SOPs in place for responding to natural gas emergencies. 

While SOPs are not considered a contributing factor to this fatality, co-development of technical SOPs 
Page 18 

One Fire Fighter Dies and Another Injured in Natural Gas Line Explosion—

Wisconsin

Report # F2018-12

with utility experts is considered an industry best practice and would be beneficial to fire departments 

nationwide. 

Recommendation #8: Fire departments should ensure that firefighters wear a full array of turnout 

clothing and personal protective equipment, including Self-Contained Breathing Apparatus 

(SCBA), appropriate for the assigned tasks. 

Discussion: While PPE is not considered a contributing factor to this incident, it is notable in this 

discussion. NFPA 1500 Standard on Fire Department Occupational Safety and Health Program

contains the general recommendations for firefighter protective clothing and protective equipment 

[NFPA 2018a]. Chapter 7.1.2 states “protective clothing and protective equipment shall be used 

whenever the member is exposed or potentially exposed to the hazards for which it is provided.” 

Chapter 7.2.1 states “members who engage in or are exposed to the hazards of structural firefighting 

shall be provided with and shall use a protective ensemble that shall meet the applicable requirements 

of NFPA 1971 Standard on Protective Ensembles for Structural Fire Fighting and Proximity Fire 

Fighting [NFPA 2018b].

The fire department in this incident provides members with a full array of turnout gear and SCBA that 

are in accordance with NFPA 1971. During the search and rescue operation of this incident, 

firefighters were instructed to remove their SCBA while searching on the burning pile of rubble to 

speed up recovery efforts. The fire Captain was in full structural turnout gear.

Recommendation #9: Fire departments should provide manual personal alert safety system (PASS) 

or tracking devices to locate potentially missing firefighters when Self-Contained Breathing 

Apparatus (SCBA) are not utilized. 

Discussion: While this is not considered a contributing factor to the Captain’s death, often firefighters 

can and do carry out their duties at a hazard scene without donning or activating their SCBAs. In this 

scenario, an SCBA with the integrated PASS device would not be activated since the SCBA would not 

be turned on. If an unexpected explosion or collapse occurs, there may not be an indication that a 

firefighter is down because the PASS would not be activated. The use of a manually activated device 

in these types of situations may be helpful to pinpoint a firefighter’s location. 

In this incident, the Captain was missing, and firefighters were looking for him in the rubble. He was 

found when members from the search crew saw the reflective portion of his right boot. An active 

PASS alarm may have alerted search crews to his location more effectively.

Recommendation #10: Building officials should be included in emergency management services 

planning committee drills. 

Discussion: Disaster preparation does not solely fall on the shoulders of first responders and 

emergency managers. Building and code officials can have a major role to play in pre-incident 

planning. Emergency management services planning committees should include fire, police, EMS, and 

building officials. Knowledge of current and past construction permits, changes to major structures, 
Page 19 

One Fire Fighter Dies and Another Injured in Natural Gas Line Explosion—

Wisconsin

Report # F2018-12

utility work, and city records can help enhance preparations and pave the way to a smooth emergency 

operation. 

Building officials should be encouraged to participate in pre-incident planning committees and be 

involved during inter-operational drills. By doing so, weaknesses may be identified, such as the 

inability to quickly pull building blueprints or building permits due to old or outdated filing systems, 

and then be improved for better access. This will provide first responders important building 

information quicker and allow the Incident Commander to make well informed operational decisions.

References

1. USDOT [2020]. 2020 Emergency Response Guidebook. Washington, DC: U.S. Department of 

Transportation, Pipeline and Hazardous Materials Safety Administration, 

https://www.phmsa.dot.gov/hazmat/erg/emergency-response-guidebook-erg

2. IFSTA [2013]. Essentials of Fire Fighting, 6th ed. Oklahoma State University. Stillwater, OK: 

Fire Protection Publications, International Fire Service Training Association. 

3. Kipp JD and Loflin ME [1996]. Emergency incident risk management. New York, NY: Van 

Nostrand Reinhold. 

4. NFPA [2019]. NFPA 1001: Standard for Firefighter Professional Qualifications. 2008 ed. 

Quincy, MA: National Fire Protection Association.

5. NFPA [2014]. NFPA 1561 Standard on emergency services incident management system. 2014 

ed. Quincy, MA: National Fire Protection Association. 

6. NFPA [2018a]. NFPA 1500 Fire department occupational health and safety standards 

handbook. 2018 ed. Quincy, MA: National Fire Protection Association. 

7. NFPA [2018b]. NFPA 1971 Standard on protective ensembles for structural fire fighting and 

proximity fire fighting. 2018 ed. Quincy, MA: National Fire Protection Association 

8. IAFC [2012]. Rules of engagement for structural firefighting. Fairfax VA: International 

Association of Fire Chiefs, Safety, Health, and Survival Section 

9. Weather Underground [2018]. Weather Underground Weather History 

https://www.wunderground.com/history/daily/us/wi/madison/KMSN/date/2018-7-10 

Investigator Information

This incident was investigated by Karis Kline, Safety and Occupational Health Specialist, Timothy R. 

Merinar, Safety Engineer and Steve Miles, Safety and Occupational Health Specialist, with the Fire 

Fighter Fatality Investigation and Prevention Program, Surveillance and Field Investigations Branch, 

Division of Safety Research, NIOSH located in Morgantown, West Virginia. An expert technical 
Page 20 

One Fire Fighter Dies and Another Injured in Natural Gas Line Explosion—

Wisconsin

Report # F2018-12

review was provided by Chief Jerry Knapp. A technical review was also provided by the National Fire 

Protection Association, Emergency Response and Responder Safety (ERRS) Division.

Additional Information

Rules of Engagement for Firefighter Survival

Disclaimer

Mention of any company or product does not constitute endorsement by the National Institute for 

Occupational Safety and Health (NIOSH). In addition, citations to Web sites 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 Web sites.