Fire Tech Brief: 5 Reasons Why Fireground Radios 'Fail'

Nearly every fire or rescue incident hot wash or after-action report will list communication as something that can be improved. Whether from a technical side where communications did not work, or from a training side where there was a lack of radio discipline, it somehow always ends up on the list. For something that is key to our success, I have always struggled with just accepting the issue as a part of the job and have proactively looked for ways to improve the infrastructure, training, and understanding of the problems. I want to review four major areas and share a few pointers to improve fireground communications.

Physics of fireground radios

It has always amazed me how we spend so much time mastering our equipment but for something as critical as a radio, we rarely teach newer firefighters how a radio works. In simplest terms, radios are a small piece of a larger network to support vital communications. They use various forms of connection (VHF, UHF, 700MHz, or 800MHz) to reach towers, repeaters,  or other radios. They generally operate in two modes, trunked (radio to tower to radio) or direct (radio to radio). VHF and UHF radios are described as analog radios whereas the 700 and 800 MHz radios are considered digital radios. When you compare the wavelength of the two most common types (VHF and 800 MHz) the VHF signals have a larger wavelength which makes them better for longer distances and building penetration. The 800 MHz radio has a shorter wavelength, and their antennas have real gain to improve efficiency which allows for more frequent reuse and better clarity.

Building materials directly affect the radio signals where denser materials like reinforced concrete and steel framing block UHF, 700 MHz, and 800 MHz signals. Energy efficiency being built into the modern house also creates issues with radiant barrier plywood and low-E glass that absorb and reflect signals. While VHF has been the choice for decades, a lot of state-driven communication systems moved to the 800 MHz radio system due to the ability to also push data over the radio. These post-9/11 infrastructure improvements added a lot of coverage areas but also created an issue where users would see signal indicators even when the audio is unusable.

User error myths

We have all heard of user error being the label for anything that happens that was within a user’s control, however, there are a few myths that need to be reviewed.

• Users failed to key up the microphone properly - Stress, especially on the fireground, also creates conditions where communication can fail. Stress degrades fine motor control which leads to shortened push-to-talk button presses resulting in clipped or rushed communications. When we train, we often do not induce stress to replicate fire ground conditions which means, our communications are calmer and clearer.
• Users do not keep the radio microphone in optimum range from their mouth - We all know that SCBA facepieces distort our voices and, in some cases, even the regulator noise can drown out the message. A NIOSH study revealed that regulator noises in particular masked consonants which are critical to intelligibility. Several options have been created to help minimize these issues, but each come with their own added challenges or issues.
• Users were unable to reach their push to talk or difficult to understand - Most radios are designed for calm, upright users in low noise environments, whereas the fireground conditions rarely allow this optimum situation. I remember going through rapid intervention drills where we tested microphone placement in a variety of conditions, the worst being a simulated collapse where you were pinned to the floor. Even the most prepared firefighters may find themselves in a situation where they are unable to speak directly into the mic.

These are not user errors as much as they are human physiology and limitations of the equipment we use to communicate. While training can help users understand the limitations and best practices, there will be scenarios and situations that hit the limitations of the equipment.

Choices that make things worse

Speaking of equipment limitations, there are several choices that can make things worse. Your choice to use a radio pocket, leather radio strap, keeping the radio under your turnout coat or on top of it, each have pros and cons. Chest-mounted lapel mics pick up PASS alarms and hose stream noise whereas shoulder mounted mics limit communication if the user is not in prime position.

A department’s choice of where to set the threshold for noise cancellation can be too aggressive and remove speech, especially if they are also using voice amplification speakers. The choice to use noise cancellation mics is not a magical fix as they are best at filtering out steady noise compared to the chaotic fire ground noises. A department may have intended to filter out diesel engine, chainsaw, or siren noise but they can also inadvertently filter out things they wanted to hear. Apparatus driver operators commonly get access to headsets, which provide hearing protection and superior radio clarity. However, they also prevent the user from hearing environmental clues such as the sound of the pump or verbal communications from others on the scene.

Infrastructure false confidence

Infrastructure increases capability at the cost of reduced resilience. Adding repeaters, especially mobile repeaters, can improve gaps in the radio network but they also create a singular point of failure. Repeaters are highly susceptible to power loss, antenna damage, and overload that can disable the entire system. Changes to building codes require building systems in buildings that block radio communications which generally work well for the false alarm or medical calls however, under fire conditions, these systems cannot be relied on.

They are also built to a minimum standard which leaves dead zones especially in stairwells and basements. When evaluating the infrastructure, we rarely can assess them under the same conditions in which they will be most needed. Radio checks by crews who are in optimum conditions (upright, calm, and without background noise) lack heat, water, stress, noise, and movement. This leads to unrealistic expectations and trust that a system will work under emergency conditions.

What improves fireground communication?

As a techie, I am also a realist when it comes to overreliance on technology. While I could give you a list of tech options to help improve communications, I also believe that discipline beats technology in this case.

• Keep communications short and structured - It is easier to fill in the missing pieces of communication when everyone is expecting a particular format of communication. There are a ton of options out there, but I wanted to touch on a CAN (Conditions, Actions, Need) report. As an incident commander, this format helped me know what to expect from the communication. If it were cut short or started late due to a mic issue, I would ask for clarification, but it reduced the chaos of scene communication and established an effective communication tempo.
• Redundancy to radios is necessary - Face-to-face communication is always best but hose line tugs, hand signals, and maintaining crew integrity minimize communication failures. This also means having a good accountability system. Color coding and unit designators on helmets, helmet fronts, SCBA, can help reduce scene confusion.
• Train with Murphy – The ideal that what can go wrong will go wrong is not setting people up fail. It is real life fire ground conditions. Practice radio use with intentional interference. Normalize missed or garbled communications. Train on site, not always in the perfect environment and figure out what to do when things like a mobile repeater fail.

Conclusion

Communication is key to success in relationships, leadership, and especially on firegrounds. Take the time to learn about the technology that you rely on. Know where the towers are, know what every button on a radio does, know how your choices impact your ability to communicate and learn other ways to communicate.