Major Event Preparedness

Your level of investment for major events depends upon your location and risk assessment. You need to invest enough to stay on air through critical events, ensuring power to your sites throughout.

The greatest barrier to effective emergency response is low levels of preparedness – lack of training, and being unfamiliar with emergency operating procedures. Technical issues come second.

This section outlines measures to prepare for major events, whether they are planned exercises, natural or man-made disasters.

Planning and preparation

Planning for critical events on a daily basis is much better than figuring it out when you are under duress! To predict emergency coverage and performance requirements you can look to local event history – is your jurisdiction at risk from floods, hurricanes, forest fires, blizzards, or earthquakes? Of course you will also need to plan for risks such as terrorist attack, multiple motor vehicle accidents, plane crashes and civil unrest.

  • Identify, protect and prioritize your critical user groups in advance, and build them into your talkgroup structure.
  • You will not have enough channels for all your users in extreme situations so your disaster planning must limit network access to critical users only.
  • Define the complexity of your interoperability needs with a matrix – who needs to talk to whom?
  • Plan how you will use encryption. Can you communicate effectively with all the necessary agencies and groups?
  • Estimate how long different disaster scenarios might leave you without power, fuel or support. You may have to be independent for 72 hours or more.
  • Invest in transportable networks that can be rapidly deployed.
  • Maintain a cache of radios that all your mutual aid partners can use. A strike team needs to know where the caches are.
  • Keep cached radios programmed, maintained and updated with the rest of your fleet – don’t discover this has not happened when you are under pressure.
  • Schedule and practice simulated emergencies with your interoperability partners annually. Take a lead from fire departments, who do this well.
  • Ensure your procedures are thoroughly documented, easy to follow and easy to find. Ideally, they will be in both electronic and hard copy.


Often, low-risk system equipment gets the attention and funding, while crucial equipment is neglected. Ironically, most money is spent on standby controllers, which are seldom used. When you prioritize, keep in mind what breaks most often. These are:

  • power (poor quality unprotected mains, un-maintained UPS or DC battery banks, un-tested generators, generators with insufficient fuel supplies),
  • antenna systems (bad lightning protection, poor grounding, poor design),
  • backhaul (operator/technician errors),
  • poor wiring (people tripping over cables in shelters or other equipment rooms).


While your level of investment for events depends on your location and risk assessment, there are some basic principles you should build in to your day-to-day planning.

  • Eliminate single points of network failure.
  • You will lose power – plan for it with dual redundancy (AC then battery then generator).
  • Estimate how long different scenarios may leave you without power.
  • Invest enough to stay on air through critical events, ensuring power to your sites throughout.
  • In a major disaster, telephone systems (especially cell phone systems) frequently fail.
  • Plan for a scenario in which your computer systems (including CAD) are not available.

Site equipment

Even with the best planning, you may be without some sites in a disaster. Good planning and system design can mitigate the effects of this on your communications.

A generator may take five to seven minutes to fire up, which may leave officers without communication at a critical time. In an emergency, utilities and propane companies may not have power to pump fuel.


What will happen to your ability to communicate if you lose a site? Some systems use geographically-distributed back-up sites (typically, mutual aid channels). Others over-provision the sites so that every important area of operations is covered by more than one site. While this is highly recommended, it is expensive and creates technical challenges, especially in multicast system configuration, requiring finely-tuning roaming performance of subscriber units.


The basic rule of thumb is to have enough capacity to handle three times more traffic than your typical weekly busy hour. Any more than this becomes impractical and costly, while less is likely to be insufficient. Verify this against your circumstances: for a smaller rural agency it may be overkill, for a large metropolitan area, you may want to plan more capacity.

In every case, you need to limit traffic on your system to those who need to be involved. Contingency plans for emergencies should include means to cut off “roamers” and anyone that does not need to participate. Depending on your configuration, allowing people to monitor activities while they are scanning means additional groups will load, which may choke your system.

Be prepared to completely isolate a site in an emergency, especially on larger multi-site systems as it will likely improve capacity for the incident.

  • Allow access to sites and groups as needed only.
  • Limit monitoring/scanning.
  • Limit the number of groups on the system.
  • Enforce incident discipline of communications.
  • Train your people to ensure they understand what is required of them.

Ultimately though, your system design should not require any substantial changes on how it is used in an emergency, if emergency capacity has been factored into the system design.

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