ICC 500 Sect 502.2 Access Opening -- Requires access opening minimum size 24" wide x 30" long.

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ICC 500 Sect 502.3.1 Vertical Access -- Requires minimum tread depth 8" and maximum riser height 9-9/16"

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ICC 500 Sect 502.3.1 Vertical Access -- Requires minimum Stair width 22" and slip resistant surface.

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ICC 500 Sect 502.3.1 Overhead Clearance -- Requires minimum overhead clearance 6'-8" or 5'-0" with signage.

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ICC 500 Sect 502.3.1.2 Handrail required on stairways having more than three stairs.

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ICC 500 Sect 502.4 Occupant Density -- Requires minimum 3 sq ft usable shelter area per occupant.

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FEMA 320 & 361 Requires minimum 3 hinge attachment points and 3 positive latch points.

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ICC 500 Sect 302303/304 Requires exterior key accessibility for post storm Emergency Entry by EMS personnel if needed when latches are engaged from the inside.

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ICC 500 Sect 305/306500 Emergency access can be made by removal of full length hinge from outside with 2- 7/16” wrenches.

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Sect 804 Loads and load combinations, Hydro-static loads, wind loads, required for the construction of shelters.

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FEMA 320/361 Our shelters have been tested by a third party engineering firm for underground structural design. All models exceed the requirements.

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NPCTS Windborne Debris Hazards -- Requires tornado shelters exposed surfaces to be designed tested to emulate wind speeds of 250 mph. 15-lb sawn lumber 2 x 4 missiles impacting exposed surfaces less than 30 degrees from horizontal at 67 mph and exposed vertical surfaces at 100 mph.

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ASTM E 1886 DESIGN TESTED AND PASSED TESTING AT T.T.U. WIND ENGINEERING FACILITY DATA AVAILABLE UPON REQUEST

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ICC 500 Sect 702.1 Requires 2 sq. in. or 4 sq. in. of natural ventilation based on location of ventilation ports per occupant.

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