For “sheltering-in”. Have plastic available with duck tape. Depending on the disaster [chemical, biological, natural], one can survive, maybe up to two weeks, depending. Pick a room in the middle of the house, with the least amount of doors, windows. If not, just put plastic sheeting on windows, doors, air- conditioning vents. And seal holes [play dough] around plumbing fixtures that’s entering through the outside wall. It’s good to do this even without thinking of sheltering-in, because of drafts….. Heating, cooling costs. And when a disaster does happen, shut off the gas to the house. That is if you have natural gas [outside of house]. Close vents…..central air-conditioning [don’t run it], fire-place flues. Anything that will let out-side air…. in.
DON”T cook using sterno, propane, or briquettes in-doors while “sheltering-in”.
Use foods [non-perishable] that require little or no water for preparation. Hope for the best.
Have 1 gallon of water per day for each person. Have bleach for purifying water, if need be……4 drops [medicine dropper] of bleach [un-scented, sodium hypochlorite] for 1 quart of water…..Stir, shake and let stand for 30 minutes, before using.
Have a [manual] can opener on hand.
Here’s a tool firefighters, first responders use, that’s very good. One among many.
A flashlight, that’s impact resistance, water resistance, or water-proof.
Light [glow] sticks.
A multi-purpose tool that cuts, open cans, bottles, removes different screws, has pliers...
Sterno fuel…….not to be used when “sheltering-in”, though.
First-aid kit.
Radio.
And of course, as you know one or two handguns [your choice] with ammo.