Trending Topics

Portable gas meters: The essential ‘E’ in PPE you should use on every call

An action plan for first responders outlines the appropriate training and skill levels needed to operate portable gas meters


Remember, the “E” in PPE stands for equipment, and gas meters and detectors are essential to incident safety – they may just save your life.

Indianapolis Fire Department

Portable gas meters and detectors are vital pieces of PPE. Every firefighter, paramedic and EMT must be skilled and knowledgeable in their proper use.

“PPE? That’s my turnout gear or latex gloves or goggles, right? So why are you saying my portable gas meter is a piece of PPE?”

Remember, the “E” in PPE stands for equipment, and gas meters and detectors are essential to incident safety – they may just save your life.


Let’s first talk about carbon monoxide (CO), probably one of the most common gases for which any emergency responder must be on the lookout. CO gas is a byproduct of the burning of fossil fuels (e.g., wood, coal, petroleum products).

Some examples of where emergency responders can encounter a CO gas atmosphere include, but are not limited to, the following:

  • Damaged or improperly installed chimney flues;
  • Improperly vented emergency generators;
  • Propane or other natural gas stoves or heating equipment that are not working properly;
  • Vehicles left running in a garage with CO entering the living space; and
  • Individuals using a propane or natural gas stove to heat their home.

Learn how to spot the signs of CO poisoning.


The Firefighter Near-Miss Reporting System reminds, “Don’t let your guard down on routine medical calls,” and share two case studies of CO incidents involving first responders.

Incident 1 summary: Firefighters responded to a medical call on an unseasonably warm day where they encountered a female occupant complaining of heart palpitations. While assessing the patient, firefighters noted that her husband was lying on the sofa in another room with his feet on the back of the sofa. When they asked the woman if he was OK, she replied that he suffered from mild dementia and frequently took that position when he had a headache.

Firefighters retrieved the CO monitor. The initial reading indicated a CO level of 700 ppm, prompting firefighters to immediately evacuate the home. Once outside, a RAD-57 pulse/CO oximeter was used to evaluate the occupants of the home and all exposed responders. Those assessments revealed elevated CO levels for everyone who was monitored; some of the responders were beginning to actively experience the early effects of CO exposure. In all, the two occupants of the home and four additional responders were treated for CO poisoning.

The incident commander declared the incident as an MCI, as there were now possibly nine victims of CO poisoning. Firefighters in full PPE and SCBA conducted a thorough assessment of the home and found a peak CO reading of 1,600 ppm in the basement.

The firefighters later learned that the occupants had turned on several air conditioners in their home due to the heat. One A/C unit was pointed at the thermostat for the furnace, which activated the furnace. For some unknown reason, the occupant had disconnected the furnace from the chimney in the basement.

Incident #2 summary: Firefighters responded to a report of a juvenile who had reportedly become sick, vomited and then fainted in the pool area of a hotel. After the responding crew had only advanced a few feet into the pool area, the ambient CO monitor attached to their medical aid bag began alarming.

The firefighters evacuated everyone from the pool area, shut down the power and natural gas lines to the pool area, and requested additional CO meters to better monitor the environment. Those CO monitors provided CO levels of 400 ppm at the door and 500 ppm near the boiler room for the pool.

Firefighters expanded their CO monitoring to include the entire hotel hallways and readings of 135 ppm were recorded. IC ordered the evacuation of the hotel for a short time while positive pressure ventilation was employed to ventilate the hotel hallways and rooms.

Read more from these incidents and the full Near-Miss reports here.



Firefighters must also consider the hazards of carbon dioxide (CO2). In 2012, in “Deaths & Injury Incidents on the Rise at Restaurants Using Liquid CO2,” a post by Jack Benton in EHS Safety News America, highlighted a number of incidents where firefighters encountered CO2 gas.

According to Benton, the primary health dangers from exposure to CO2 gas are:

  • Asphyxiation: An unintentional release of any gas, particularly CO2 gas, in a confined or unventilated area can rapidly lower the concentration of oxygen to a level that is immediately dangerous to life or health. Firefighters and prehospital patient care providers must exercise caution when entering a truck or room where solid or gaseous CO2 is stored.
  • Concentrations greater than 10% in air: The relative amounts of products and reactants depend on their concentrations and can lead to chemical equilibria. The definition of chemical equilibrium is the point at which the concentrations of reactants and products do not change with time. It appears the reaction has stopped but in fact the rates of the forward and reverse reactions are equal, so reactants and products are being created at the same rate.

Read Next: Vaccine storage: A firefighter’s guide to dry ice handling and hazards


In March 2021, the NIOSH Firefighter Fatality Investigation and Prevention program (FFFIPP) urged fire departments to ensure that firefighters responding to natural gas or propane incidents:

  • Use gas detection equipment and do not rely upon their sense of smell to determine if propane or natural gas is present.
  • Understand that the odorant in natural gas or propane can fade.
  • Are trained on the proper calibration, maintenance, and use of gas detection equipment to determine if a potential explosive atmosphere is present.
  • Recognize that the lack of odor can result from the natural gas or propane contacting soil, concrete, and a wide variety of building materials such as drywall, wood, and new piping storage tanks.

Read the full advisory here.


With all the firefighters know about exposure risks, it’s essential that they take key steps to protect their health:

1. Know what meters are available for your use. While there are several different types of portable gas meters available, the 4-gas portable gas meter is a popular choice for fire departments. A 4-gas monitor can provide atmospheric readings for CO, oxygen, hydrogen sulfide (H2S) and lower explosive limit (LEL). Portable CO monitors have evolved into small portable units that can easily be attached to medical aid bags so that a monitor is always with prehospital patient care providers even before they make patient contact.

2. Become thoroughly skilled and knowledgeable with those meters. Read the manual provided by the meter’s manufacturer. Pay particular attention to the recommended calibration procedures and troubleshooting processes.

3. Train on how to effectively use the portable gas meters available for your use. David Loh, principal operations manager at Incident Ready, LLC, clarifies the Operations-level and Technician-level responsibilities in NFPA 472: “First and foremost, any first responder who is expected to respond to a known hazardous materials incident must be trained as an operational level responder as per OSHA 1910.120 (q) and or EPA 40CFR311. Metering/Air Monitoring is an Operations Level skill as outlined in NFPA 472’s Mission Specific competencies (Chapter 6).” Loh adds, “If a fire department has multi-gas meters, users must be trained to operate, understand physical properties, what the meter is telling them, and environments where they should not use a multi-gas meter.”

Further, make recurring training on your meters a part of your existing training program. Think of having properly operating gas meters and knowing how to use them on par with SCBA training.

4. Begin the ID and recognition process early. 911 call reporting incidents like “CO detector is sounding” or “car is running in the garage” should heighten a firefighter’s sense of situational awareness. Loh notes: “The initial impulse to open the electric overhead door or turn on a garage light could cause an explosion. Entering the garage without PPE and SCBA and multi-gas detection could be fatal to the first responder(s).”

5. Use your portable gas meters on every response that requires you to enter a structure. By the time you enter a home and evaluate what’s wrong with an occupant of the home, you can become part of the problem yourself. As Loh explains: “It’s one of the most important tools in our toolbox. Plainly stated, a CO [or CO2] environment is an IDLH environment, and minimal PPE worn should be to protect first responders from its respiratory, flammable and explosive properties. [Firefighters] must eliminate potential ignition sources, establish a hot, warm, and cold zones and [begin] ventilation [of the space]. EMS personnel should avoid rushing into any potential hazardous environment without appropriate PPE.”

6. Acknowledge every use of your portable gas meter has value. If you detect a hazardous gas, that’s a win! And if you don’t, you’ve just completed another training session, and that’s another win!


Portable gas meters and detectors are one of your most important pieces of PPE. Learn about the symptoms of poisoning, not only to recognize it in patients but also fellow crewmembers. And train on detection just as you would your bread-and-butter fireground operations.

Battalion Chief Robert Avsec (ret.) served with the Chesterfield (Virginia) Fire & EMS Department for 26 years. He was an instructor for fire, EMS and hazardous materials courses at the local, state and federal levels, which included more than 10 years with the National Fire Academy. Chief Avsec earned his bachelor’s degree from the University of Cincinnati and his master’s degree in executive fire service leadership from Grand Canyon University. He is a 2001 graduate of the National Fire Academy’s EFO Program. Beyond his writing for and, Avsec authors the blog Talking “Shop” 4 Fire & EMS and has published his first book, “Successful Transformational Change in a Fire and EMS Department: How a Focused Team Created a Revenue Recovery Program in Six Months – From Scratch.” Connect with Avsec on LinkedIn or via email.