Print Friendly, PDF & Email

Several large fire departments in the U.S. have determined that digital radio systems are not suitable for use on the fireground. One of the most significant problems they have identified occurs when using digital radios in noisy environments. The computer software in the radio that converts the spoken word to digital data cannot adequately distinguish between human voice and noise. The voice is masked by the noise much worse than analog radios.

In response to this issue, the International Association of Fire Chiefs (IAFC) created a Digital Problem Working Group (DPWG) to provide expert input to the National Institute of Standards and Technology which conducted tests in concert with NTIA to confirm the problem and identify potential solutions. The results of the study substantiated what the fire departments reported.

The NIST/NTIA tests were specific to the noises that could be expected at the scene of a fire or rescue incident, and focused on sounds from the following sources:

  • Fire truck pump panel
  • Firefighter Personal Alert Safety System (PASS) devices
  • In-mask low-air alarm
  • K12 circular saw
  • Chain saw

I believe this problem extends beyond the narrow scope of the noise sources that were tested by NIST/NTIA. Why would this problem be limited to radios used by firefighters and noises commonly heard at fire incidents? Similar problems could occur for police officers using digital radios in the following situations.

  • Low to moderate wind noise when a police officer is transmitting from a portable radio outdoors
  • Storm noise including wind and rain when a police officer is transmitting from a portable radio outdoors
  • Traffic noise when transmitting from a portable radio while standing outdoors next to a busy freeway
  • Transmitting from a mobile radio in a patrol car while a canine is barking loudly in the back seat
  • When transmitting from a handheld radio in the presence of a loud crowd of people or when loud music is present, such as rock concert
  • When transmitting from a mobile radio during a pursuit while siren noise is present

If you are a police officer or dispatcher and have personally experienced problems with digital radios in noisy environments, please click here to tell me your story.

Links to IAFC, NIST and NTIA documents related to the tests.

Related information: