Most survivalists,preppers, etc., make judgements based on the Rule of 3's. The rulesare: 3 minutes without air, 3 hours without shelter (in extremeenvironments), 3 days without water, 3 weeks without food. Those arebasically the limits of how long you have before you are dead. Nowkeep in mind that that is how long before you die. While I mayphysically survive for 3 minutes without air, I can tell you that Ican only hold my breath about 45 seconds, and much less if doinganything physical. You may be alive at 3 days without water, butafter 24 hours you are a hurting unit, and brain damage starts atabout 48 (less if you are physically active or in a hot environment).Yes, you can live for 3 weeks without food, but you will be verymiserable after day 1, and extremely weak within 3-4 days. Alive?Yes, but not effective, not to mention miserable. Still, it is a goodway to look at priorities.





Best way to startout in basic preparedness is to assess your situation. No twohouseholds are exactly alike, no two situations are exactly alike,and no two emergency plans are exactly alike. Some questions you maywant to ask yourself include: What is most likely to happen to causedisruption? What is the closest hazard (nuclear plant, train tracks,fertilizer plant, etc. Something that would cause significantproblems) to you. Are you rural, urban, or suburban? What level orpreparedness do you feel is appropriate? What is your financialability to start preparedness? What lifestyle do you want to live?What is your work commute, and what if you cannot come home as normalfrom work due to an emergency? Do you travel a lot? Do you move alot? Can you hide your preps, so visiting company does not see them?Who depends on you? What do YOU depend on? Do you have electric heat,natural gas, or city water that you are dependent on, for example?





Once you establisha list of risks and dependencies, you can use a crude equation tocalculate what you should prepare for first. To score an event, youtake the event, multiply its likeliness of occurring to its severityif it occurs, both on a 0-10 scale. This is called Risk Assessment.This particular scale and the calculations are very crude, but is easy todo.





Example 1:





Power outage (within the year);Likeliness of 4 (on a 0-10 scale). Severity of 2. Score is 8.





HAZMAT spill attrain tracks ½ mile away, prompting evacuation; Likeliness of 2.Severity of 10. Score is 20.





Even though apower outage is twice as likely, the severity of a HAZMAT spill ismuch more severe, thus you should FIRST have plan to deal with thehazmat spill (which is usually to leave, or "bug out”).





Example 2:





Zombie Apocalypse;Likeliness: 0.001. Severity of 10. Score is .01





Flu outbreak;Likeliness of 6. Severity of 3. Score is 18





Even though aZombie Apocalypse is much more severe, it is far better to preparefor a flu epidemic. These numbers are just generalizations and notscientific, but you get the idea.





Remember in yourrisk assessment the rules of 3. The first rule is 3 minutes withoutair. In the event of that HAZMAT spill a half mile away, you need toevacuate the area because toxic substance X is airborne. You can onlyhold your breath for 3 minutes, less when stressed and beingphysically active (like running for your life). If you lived ½ milefrom the tracks, you may want to consider NBC (Nuclear BiologicalChemical) full respirators for every member of the family, plus a fewspares. You still need to evacuate the area, but you are breathingfiltered air while you are getting out, possibly saving your life, orcancer later.





Re-consideringexample #1, what if you are completely dependent on electricity forheat, water and keeping your livestock alive, and you live in an icestorm prone area? Likelihood goes up to 6, as you KNOW you will bewithout power at least for a weekend every winter. Since you don'tlike freezing to death and your plumbing freezing up, the severity isnow a 7. That now scores at 42. If you live in, say, Florida, youknow a hurricane will take out power eventually and it may be yearsoff, but you have a hand pump shallow well in your yard, and don'tkeep much for frozen/refrigerated food. No power is no big deal, justno air conditioning. Likelihood of 3, severity of 2. Score is 6. Sameevent, but different circumstances warrant a different preparationresponse. All households are different, even in how they respond to the same situation.





I find you cangive yourself a more honest response by going down your list ofpossible events, and only fill in the likelihood first. Then go back,cover up your likelihood answers, and fill in the severity. Even dothis a couple days later. This just promotes more reality, instead ofmanufacturing results by calculating the scores in your head.Obviously, this should be done with your spouse as a teamquestionnaire  
What is most likely to happen first? Usually, this is a personal SHTF: Financial; job loss, illness, something expensive breaks. All of those are usually fixed with money. This means have financial savings: at LEAST 3 months NORMAL expenses in CASH. Ideally, you should strive for an additional 6-12 months expenses in the bank in a separate savings account than your normal transaction account.
Then rule of 3s. Remember: food is actually last on the priority list.