If you’ve been involved in prepping for any length of time or even just done some research on the subject, you’ve probably come across some variation of the Rule of 3s. I’ve seen it expressed a lot of different ways, but the most common version goes something like this:
- You can survive 3 minutes without oxygen or with severe bleeding
- You can survive 3 hours without a stable core body temperature
- You can survive 3 days without water
- You can survive 3 weeks without food
The rule makes a great starting point for planning your preparations, but I’ve found that many people tend to take it too literally without really understanding all of the ramifications. I also believe that there are some additional critical elements that should be included, so over the years I’ve expanded it in several areas. The goal of this article is to evaluate what the rule means, some additional realities that apply, and discuss some enhancements that I find useful.

