Sewage gases from toilets post shtf

[Scythe13]

First thing to do, empty the cistern thing above the toilet. That's clean enough to drink, as long as you've not put anything inside it. That's a good 4 litres plus. After that...just leave it be, and make sure nobody uses it. If the water's off, then so be it. What you don't want to do is use the toilet and have the last flush be 4 litres of good water down the pan....literally.

After that, I think I'd close the bathroom door, then just open the bathroom window. Suddenly that room becomes a no go room, and problem solved. If you're worried about gasses getting into the house, you could use a snake shaped draught excluder along the bottom of the door. That'll fix the problem, and will stop any build-up of pressure.