In December 2014, the National Institute of Standards and Technology (NIST) released the results of a study testing the effects of high temperatures on the performance of handheld portable radios (PDF). These tests were conducted after portable radio performance problems were noted in several line-of-duty firefighter fatalities investigations by the National Institute for Occupational Safety and Health (NIOSH).
In 2012, NIOSH released a report on the line-of-duty deaths of San Francisco Fire Department Lieutenant Vincent Perez and Firefighter Paramedic Anthony Valerio, both of whom died during a single-family-residence structure fire on June 2, 2011. The NIOSH report recommended that "first responder radio manufacturers, research/design facilities and standard setting bodies should continue research and efforts to improve radio system capabilities."
The study tested portable radios from seven manufacturers using four different thermal classes. The testing regime had four thermal classes that included the exposure of portable radios to heightened temperatures over limited time periods.
The test for thermal class I (212˚F over 25 minutes) saw all radios operating throughout the period with frequency stability.
Radios tested under the thermal class II scenarios (320˚F for 15 minutes) did not fare as well. Four of the seven radios were not able to transmit throughout the entire test period. Although the three remaining radios transmitted throughout the time period, they experienced more than five PPM deviations from the carrier frequency in the mean maximum-power frequency.
Testing under thermal class III and IV were not completed as they both included exposure to higher temperatures.
The National Fire Protection Association (NFPA) performance standard for firefighter portable radios states that "portable radios shall be manufactured for the environment in which they are to be used and shall be of a size and construction that allow their operation with the use of one hand."
The NIST study also stated that many portable radio manufacturers list the maximum operating temperatures of 60˚C (140˚F) for radios used by firefighters. The chasm between the current standards and the operational needs of firefighters is a key focus of the new NFPA 1802 standard on personal portable (hand-held) two-way radio communications devices for use by emergency-service personnel in the hazard zone.
In a July 2014 interview with Radio Resources Media Group, NFPA 1802 Chair Bob Athanas stated, "for many years there have been issues with portable radios not being robust enough to survive the environments that we work in daily. Now we have a chance, with both user and industry input, to ensure that we can create a new standard for firefighter radios."
The ability to communicate under adverse field conditions remains a critical topic for the health and safety of all public safety. The ever-changing environment where firefighters are required to work requires continued research to keep them safe. As communications hardware solutions evolve, it is vital that we ensure they are suitable and reliable for the public safety community.