I built a cinder block box in a wedge shape. Think an upside down pyramid lined with 1/4 inch steel plate. Expanded metal to make the floor flat, some shelves, a tin roof, grounding straps and a lightning rod. Powders in original containers inside 40mm ammo cans. I have those little moisture absorbers in each ammo can. If it ever go's bang it'll probably knock some small plane out of the sky but I should me safe.
The number one cause of death in the 20th century. 290,000,000 citizens were first disarmed and then murdered by their own governments. This number does not include those killed in war.
We're from the government, we're here to help