Lifted from SurvivalBlog and modified.

Industry has developed a procedure called "Process Hazard Analysis". If you’re responsible for the safe operation of a facility of some kind, you gather your engineers, technicians and operators together and discuss the risks involved in running your plant. Big picture it works like this; you pick an event, and rank how likely it is to happen, the severity of the consequences if it did, and any safeguards in place to prevent that particular event from happening. With this prioritized list you are able to see where to put your maximum effort. If you think of an “event” as a condition that produces an undesirable result, then you can see how we can apply this process to our preparedness efforts.

Make 6 columns down a piece of paper. Title the first "category/event", the second "Likelihood", the third "Consequences". "Safeguards", "Total" and "Action" are the titles for columns 4, 5, and 6.
The rankings for the “likelihood” and “severity” columns will be 1 through 5, with 1 representing "highly unlikely" (for likelihood) and "Insignificant" (for consequences), 3 representing "Probable" and "Serious but Repairable", and 5 representing "Highly Probable" and "Financial Ruin/Fatality". (I'll include a complete list of the rankings I use in an appendix at the end of this article).

So, for example, if I picked a category of "Civil Unrest" and an event of "Riots", my thought process would go like this: There has never been a riot in my hometown and it's very unlikely there ever will be, so "Likelihood" would get a rank of 1. I live a ways out of town so, even if there was a riot in town, it's very doubtful that it would spread to my place, so "Consequences" gets a 1. I have locks and an alarm system and a big dog, so I'm "Confident" in my safeguards, I'll give them a 3. You can see that I don't need to spend a lot of resources preparing for riots. On the other hand, you may live in a neighborhood that has experienced nearby riots. You rankings would come out different and perhaps indicate that you should spend some time thinking about how to mitigate that risk. Note however, that a category of "Civil Unrest" with and event of "Burglary" would rank higher in my situation, because that particular event has happened in my area.

Had I chosen a category of "Natural Disasters" and an Event of “Forest Fire", my likelihood rank would be 5 (because forest fires have occurred in my area). The consequence rank would be 5, because the worst case consequence is a fatality. My safeguards, (detectors, and extinguishers) are adequate but could use improvement, so safeguards get a 2. Add column 2 (likelihood) and 3 (severity) and subtract column 4 (safeguards) and I have a total of 8 out of a possible 10, a high priority. You can see through this extreme example that, it makes more sense for me to focus my efforts on upgrading my fire plan, than it does preparing for a riot. I should probably place a higher priority on fire extinguishers than firearms, hard to do given the emotion of today’s situation. Examination of your situation may well result in a different conclusion. The important thing is that emotion is removed from the decision making process.

We all have a tendency to “lock up” when faced with an intimidating task. It is my hope that, by introducing this decision making process, you can remove the paralyzing emotions from the decisions that must be made. By thoughtfully following the process, you’ll create a touchstone that will anchor you when self-doubt or well-meaning friends criticize your actions, and you are tempted to procrastinate or worse. If your beliefs don't impact your actions then they're just worthless mental baggage. How many times have you heard the word "unprecedented" lately? That means that we have never been in this situation before, not in all of mankind's history. So we really have no idea how this will end. There is still time to act, the canoe hasn't tipped yet. Use this matrix to assess where you are in the preparedness process and, most importantly, act on your decisions.

Add the Likelihood and Severity numbers, and subtract from that the safeguard number for a personalized risk ranking of a specific event.
You can see that, events with high likelihood, severe consequences and low safeguards are going to require action, say any event with a total risk ranking of 8 or more. Total risk of 5-7 deserves some serious consideration. Total risks of less than 4 are low priorities. If you decide an event requires action, it may be possible to add safeguard points, and diminish the risk, with simple lifestyle changes before committing resources that could be better used elsewhere.

The following is an example of a Crisis Decision Matrix. (Modify to fit your particular situation.)

Category	Event Likelihood	Consequences	Safeguards	Total	Action
	1. Has not happened to you or in your area 2. Improbable/unlikely 3. Possible 4. Probable, likely 5. Has happened to you / in your area.	1. No significant consequence 2. Disagreeable, minor physical/financial loss 3. Significant but repairable 4. Major injury, financial hardship 5. Financial ruin, fatality	1. None 2. Low confidence, needs improvement 3. Confident, has been adequate 4. Extremely confident 5. Absolute confidence	Likelihood + Consequences –Safeguards = Total
Civil Unrest –Riot	1	1	3	-1	None
Civil Unrest – Burglary	5	3	4	4	Look into improving my security system with cameras and a DVR
Natural Disasters – Fire	5	5	2	8	Need to improve fire detection ability and devise family contingency plans for specific fire scenarios. Research “Firewise” principles for structures in high risk areas.
Zombies - Romero	1	5	2	4	Look into improving security and preparation
Zombies - Rage	1	5	2	4	ditto