In order to effectively coordinate a large number of volunteers in a crisis, good real-time communication is vital - ideas must be floated and consensus developed in a very short space of time. Answers to questions cannot wait.
Our experience involved two real-time communication tools, Skype and IRC. Both fell well short of ideal. From this experience I have derived a set of key features for the crisis real-time communication platform of the future.
Firstly, it must be easy to join. IRC is too difficult, requiring setup of clients, server names and ports etc. Similarly the Skype requirement for invites prevents people from easily joining (and of course, they must have Skype). Ideally, a web link should be all that is needed initially.
Channels must be named in a simple fashion based on their tasks. A channel for training should be "Training", etc. When such channels are created, they should be the only place in which the related issues are discussed, and relevant channels should be simple to find.
All individuals should be identified by their real names. While aliases are common on the internet, in a crisis mistaking one person for another can be a serious problem. Best to stick to one standard, and everyone has a name.
Ideally, individuals should be tagged with their primary role, be it "Developer", "Designer" or "Disaster Coordinator". A crisis brings together many unfamiliar people and understanding their role helps understand their perspective, adding context to their words.
The chat software must be able to operate in the background on a computer. It should not demand attention in normal operation, and yet when someones name is typed (or perhaps the @name 'callout'), it should be able to generate a bell and highlight so that they can answer questions promptly.
The ability to review the complete history as well as solid searching are core functions. These allow participants to get up to speed quickly with discussions that have happened overnight or even while they were at lunch, regardless of whether their computer was logged in at the time.
Finally, and almost without saying, the chat system must be utterly reliable, running off a completely different platform from that of the primary crisis response software so that systems admins etc can continue to coordinate in the face of system failure.
The very definition of crisis involves the unexpected. All the fancy tools and processes in the world will not help if they cannot be adapted to meet the precise nature of the problem at hand, and that adaption places heavy demands on communication between members of the volunteer team. Powerful real-time communications are a vital part of the crisis tool kit.