I had no idea that the United Nations has already propagated six frequencies (and six repeater pairs), three in VHF, three in UHF, for disaster responders. These frequencies are not, in my experience, common knowledge among commercial radio vendors in the United States, and don’t appear to be referenced on the relevant pages on the FCC website, so it’s possible that we’re not a signatory to the agreement.

Here’s what’s brilliant about this idea – within certain distances along radio bands, it’s critical to have agreed-upon frequencies. And the cost keeps decreasing, as crystal-less, programmable radios which often have 16, 32, 64 or many more “channels” (frequencies or “repeater pairs” – two frequencies combined for signal boosting without feedback). So an international standard for all disaster workers to have at least three channels in common is, in and of itself, excellent policy.

An expert at the United Nations OCHA (Office of the Coordinator for Humanitarian Affairs), Hans Zimmermann, seems to have been the originator and proponent of have three frequencies in the V

HF band, and three in the U HF band, is brilliant. Simply put – VHF transmission tends to go farther, but is more easily interrupted by terrain and structures; UHF lacks the reach – the transmission distance – of VHF – but is more effective at penetrating buildings, such as high-rises like the former World Trade Center towers 1 and 2. Having both options makes it possible for responders to communicate over greater distances when unobstructed – and in and around large buildings, merely by switching amongst agreed-upon channels.To the extent that this proposal is adopted, it will save lives. This puts Mr. Zimmermann, in our view, on the same plane as John Snow and Joseph Lister. Let’s hope that this becomes the standard among responder organizations everywhere; we don’t know about the rest of the world – but we suspect that, among NGO responder groups in the United States, these frequencies aren’t well known.

Here are the frequencies, published on Relief Web: Emergency Telecommunications:

Narrow band frequencies for inter-agency coordination and safety and security communications in international humanitarian assistance, as adopted by the fifth WGET Plenary Meeting, Geneva, 20/21 May 1997, and revised by the eight WGET Plenary Meeting, Washington DC, 7 and 8 June 1999)

Within the spectrum allocated to land-mobile service in the VHF range:

• Primary Channel (A):
• Simplex: 163.100 MHz
• Duplex: Repeater transmits on 163.100 MHz
• Repeater receives on 158.100
• Alternative Channel (B):
• Simplex: 163.025 MHz
• Duplex: Repeater transmits on 163.025 MHz
• Repeater receives on 158.025 MHz
• Alternative Channel (C):
• Simplex: 163.175 MHz
• Duplex: Repeater transmits on 163.175 MHz
• Repeater receives on 158.175 MHz

Within the spectrum allocated to land-mobile service in the UHF range:

• Primary Channel (UA):
• Simplex: 463.100 MHz
• Duplex: Repeater transmits on 463.100 MHz
• Repeater receives on 458.100
• Alternative Channel (UB):
• Simplex: 463.025 MHz
• Duplex: Repeater transmits on 463.025 MHz
• Repeater receives on 458.025 MHz
• Alternative Channel (UC):
• Simplex: 463.175 MHz
• Duplex: Repeater transmits on 463.175 MHz
• Repeater receives on 458.175 MHz

Notes:

1. No CTCSS tone should be programmed on the receivers; for the transmitters a CTCSS tone is optional and might be useful if an already existing repeater on the above channels can be used. The most common CTCSS frequency appears to be 141.3 and this can be programmed on the transmitters (only) if the equipment has CTCSS capability.
2. Different from the regulations applicable to the maritime and aeronautical mobile services, there is no international allocation of channels within the land mobile services bands. The above frequencies are therefore not allocated or protected under international or national regulations; their registration in a footnote in the ITU Radio Regulations will however be sought in the next appropriate conference. The channels may be occupied by other services, including local/national services involved in a disaster relief operation. It is the responsibility of the Telecommunications Coordination Officer (TCO) to select one of the alternative channels, in case the primary channel is already in use.
3. The channels are named by letters in order to avoid confusion with the various channel-numbering systems used by the institutions concerned. The channel number corresponding to the Safety and Security Channels A, B and C should be clearly marked on each transceiver.

Via the United Nations’ ReliefWeb.