Shelter types and standards
The main types
- Garage in-ground: a steel box set into a cut in the garage slab. Common in newer suburbs.
- Outdoor in-ground: buried in the yard, away from the house; check drainage and the city permit first.
- Above-ground safe room: steel or concrete room anchored to the slab, easier for anyone who can't manage stairs (Tulsa Planning Office: Install a Storm Shelter).
Size
The Tulsa Planning Office suggests at least 3 square feet per person, plus room for pets and supplies (Tulsa Planning Office: Install a Storm Shelter).
Standards
- FEMA P-320 covers residential safe rooms; P-361 covers community ones (FEMA P-320 (2025), FEMA Safe Rooms).
- Ask for ICC 500 testing paperwork for the exact model (Tulsa Planning Office: Install a Storm Shelter).
Water table
On about 52% of Tulsa County's mapped land, soil stays wet within about 6 feet of the surface for part of the year (FoundationSoils Tulsa County soil summary (USDA SSURGO, data as of Oct 13, 2026)). Ask in-ground installers how they handle water.
Last checked Oct 23, 2026.