Via Emergency Management Magazine: Best Practices for Constructing an Emergency Message

Message label.
Identification of emergency message

Who’s speaking.
Identification of the official agency issuing the warning and potentially any relevant associated agencies.

Who the Message is for.
Statement of the targeted audience for which the message is intended. This should include specific geographic location boundaries.

What they should do, by when.
Explicit instructions on what actions citizens should take and in what timeframe. This should also include an explicit statement describing people who are NOT to take action.

Why they should do it.
A statement on the risks associated with the emergency and what specific consequences may be faced if action is not taken.

Repeating of who the message is for and what they should do within the required time frame.

End: Message label and pending information.
Close out the message with the alert identification and any instruction on where additional information can be obtained or where citizens should look for updated information as the situation changes.

Here’s a cool post via lots of people, originating with Dr. Thomas Mileti, on what your emergency message should look like.

My take on this is that it’s very good, though a bit proscribed. A lot of times, we might not know all of the answers to all of those questions. In that case, it’s important to acknowledge that we don’t know some important point, but describe the process we are undergoing to get that information.

As if I’m one to comment on Dr. Mileti’s work.