What's in Our Air - Shelby Willis, Divison Chief EMS Largo Fire

What’s in our Air?

Recently our department added an air monitoring policy to our standard operating procedures. The policy instructs personnel to monitor any environment that is determined to be immediately dangerous to life and health. Shortly after this policy was put in place the department mitigated two structure fires that taught our personnel first-hand the importance of air monitoring. The circumstances surrounding these calls were not unusual, nor were the fires anything other than what we have been doing for many, many years. However, without the addition of this policy our department and the personnel could have changed forever.

Brittany Bay Apartments
In the middle of the night, a structure fire call comes in for a second floor apartment fire, fully involved. The apartment was located in a large complex that houses 20+ buildings with 8 apartments per building. The apartments are located with 4 upstairs and 4 down. A central stairwell ran through the middle of the complex and provided the only means of ingress and egress for the residents and the firefighters.

The fire was located in the upstairs left apartment. The fire was contained to that unit, but the unit was fully involved upon arrival and sustained a lot of damage. The entire building was evacuated and all the residents were safely removed from the building.

Our department had just begun a new air monitoring program and much of our personnel were unfamiliar with the process. In-house training had recently been conducted on the
air monitoring policy and the new monitoring equipment. Department personnel were familiar with the dangers of carbon monoxide, but the department did not have a history of monitoring for other gases at fire scenes. The training had placed a large emphasis on hydrogen cyanide gas and our ability to monitor for its presence.

The personnel at that scene did a great job that night. They contained the fire to the unit of origin and no one was injured. Post-fire, the safety officer requested that the fire unit be monitored to determine air quality for crews on scene. The apartment was well ventilated and it was determined safe for the fire inspectors to be allowed access to the structure.

Subsequently, the residents were getting anxious to return to their homes. Past practice would have fire crews checking for extension in all surrounding units, pretty standard procedures. Ventilation would have been requested based on the amount of damage seen and the amount of smell present. If it smelled bad, we ventilated. If there was no damage and no smell the residents could return. Luckily, this was a past practice. The department's air monitoring policy required all units to be assessed, monitored and only when the units tested safe could the residents return.

All units checked out with the exception of the lower unit on the opposite side of the building. This unit had cyanide levels above 20 ppm and required extensive ventilation before it was determined safe for the occupants to return.

Our department learned first-hand how important it is to monitor the environment. Past practice would have allowed every resident in that building to return to their homes by the smell test alone. Lucky for us, past practice no longer comes into play for our department.


The second call occurred almost a year following the implementation of our air monitoring policy. Our personnel by this time were well versed in the process and it was no longer a question of “Should we monitor?” but “What did you get when you monitored?”

A fire occurred in a small apartment complex when a resident left a pot cooking on the stove and left the home. A bystander noticed smoke coming from the apartment and called in the fire. Upon the arrival of the fire crews there was no visible smoke or fire from the outside, and upon entry the crews reported light to moderate smoke inside the apartment.

Further investigation revealed that a pot on the stove had caught the cabinet above on fire. The fire was out, but the cabinets had smoldered for several hours. The interior crews called for ventilation and air monitoring. This type of call has the potential to get fire crews excited. A fire in an apartment and it is not known if a resident is home. Quickly the excitement is lost when it is revealed to be “just a pot on the stove”.

However, this is particularly the type of call that has the potential to harm unsuspecting fire crews and kill the homeowners.

The air quality in this unit would not have permitted survival by the resident and would have incapacitated the fire crews in a short amount of time. The CO level in the apartment read 160 ppm and an HCN level of 30 ppm. Fortunately, the resident was not home and crews went into the structure on air and maintained that level of protection until the air quality reached a zero for CO and HCN.

As one of the department’s Health and Safety Officers I cannot help but wonder what would have happened if we had allowed the residents to return to the apartment building without testing the air quality, or if our crews attempted to mitigate the kitchen fire without an SCBA.

The point of this article is not to show how good or bad we are or were. It is to show how important it is to know the environment in which we work every day - for our safety and the safety of those we protect.

Shelby Willis
Division Chief Emergency Medical Services
Largo Fire Rescue
Largo, Florida

Largo Fire Rescue has 6 stations and 145 paid career personnel. The fire district covers 30.5 square miles of Urban/Suburban area and run approximately 22,000 calls annually with 10 ALS units and 2 BLS units.