National 800MHz Mutual Aid Channels
The Federal Communications Commission, which controls the use and assignment of radio frequencies, designated five channels in the 800MHz band to be available across the nation for emergency communication between public safety users. These channels allow any public safety user with an 800MHz radio to interoperate with other responders that normally use a different system. These channels can also be used when public safety users respond to emergencies outside the coverage of the radio system they use normally.
The five channels were designated for specific uses. One was set aside as the calling or hailing channel to reach other field users and communication centers. The other four were designated as tactical or operational channels, to be used for user to user communication.
Initially, the FCC did not establish a common naming system for these mutual aid channels. Agencies across the nation began programming them into their radios and all named the channels differently.
One county may have named them as “Call” and “Tac 1” through “Tac 4”. An adjacent county may have named them “Mutual Aid 1” through “Mutual Aid 5.” The end result was, depending on who you tried to communicate with, the same channel had multiple names.
Eventually, a standard emerged calling these channels 8iCall and 8iTac 1 through 8iTac4. Many agencies decided not to reprogram their radios with the new names, resulting in more confusion.
With rebanding (what is that?) on the horizon, a new naming standard was developed. Butler County uses the new names, developed by the National Public Safety Telecommunications Council (NPSTC) in 2007, and has urged its neighbors to do the same as they complete rebanding. Our region and the state formally adopted the new national naming plan in 2010.
Download the NPSTC Standard Channel Nomenclature Report (PDF) on all public safety interoperability channels.
Medical Helicopters and Rebanding
Helicopters in our area, including Air Care and Care Flight, are now operating on the rebanded national mutual aid frequencies. See this post for more information.
Your typical assignment for a medical helicopter will be 8 TAC 92D and 8 TAC 94D in Zone C.
The guide on calling medical helicopters for dispatchers may be helpful to review.
Things to remember:
- These channels are for public safety emergency use only.
- These channels can be used nationally.
- 8 CALL 90 is normally for calling only. Operations should be conducted on a TAC.
- You may use 8 CALL 90 to attempt to hail a communications center in an emergency.
- Simplex/Direct mode is recommended for on-scene communication.
- Simplex/Direct mode is used for communication with helicopters.