Dutch site Denkvooruit (dutch; translation) has instructions about the kind of emergency bag you should have at home in case of a national disaster. And although the site says it only suggests a list of items to put in there, there is room for improvement.
For instance, most of the items are run on batteries. A wind up torch like this one or a solar powered/crank up radio in stead of a battery powered ones might be a better suggestion. In stead of bottles of water a water purifier/purifier bottle or how about using a flint in stead of matches. Not to mention that you could put it all in a solar bag to power other items (like cellphones). These items are more durable (not to mention more environmental) making for a better lifespan.
Don’t get me wrong: initiatives like this are highly recommendable. But it seems that the items mentioned on the site have a limited time of use. And when it comes to disasters you want the stuff in your emergency bag to be as durable and usable for as long as it takes.