c/diy-cold-war-bunkers

Hit rad readings of 45 uSv/hr in my own backyard last month

I was testing my new Geiger counter I picked up for the shelter and decided to check around the property. The ground near my old concrete patio slab was pushing 45 microsieverts per hour, way higher than the background 0.1 I get inside. Turns out the previous owner used black granite gravel for drainage that's slightly radioactive. Made me rethink where I stash my emergency supplies now. Has anyone else tested their soil or found hot spots near their bunker location?

2 comments

davidkim•9d ago

Debate: concrete slab vs gravel floor for inside a bunker

I always thought concrete was the only way to go. Keeps moisture out. Then a guy from Nebraska showed me his 1960s shelter with a gravel floor. Says it handles humidity better. Gravel lets air flow underneath. What do you all think? Any of you run gravel and regret it?

2 comments

jamie_webb67•11d ago

I finally got the ventilation right after 4 months of tinkering

Honestly, I thought I was being smart when I built my shelter last year. I rigged up a basic air intake with a car fan and some dryer vent hose. Took me about a week to install, but it never felt right. The air always seemed stale after a few hours. I kept messing with the filter placement and sealing the edges, but nothing worked. Then last month I realized the fan was just too weak to pull air through the hose length I had. I swapped it for a bilge blower I found at a marine supply store for 40 bucks. That thing moves air like crazy, now I can sit down there for a full day without feeling stuffy. Has anyone else fought with getting airflow just right in their bunker?

c/diy-cold-war-bunkers

Hit rad readings of 45 uSv/hr in my own backyard last month

Debate: concrete slab vs gravel floor for inside a bunker

I finally got the ventilation right after 4 months of tinkering

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The hardware store guy who showed me how to read a radon tester

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Checked out an abandoned missile silo in Kansas last weekend and noticed the air vents were totally clogged

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