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Two-Way Radio Coverage (NFPA 1221)

In-Building Coverage · IFC 510 · RSSI Compliance · Coverage %

When to use: Use to verify public safety in-building radio coverage compliance per NFPA 1221 and IFC Section 510. Enter measured RSSI levels and coverage area/point data from a radio survey. The calculator checks inbound and outbound signal levels against the jurisdiction's minimum thresholds and verifies the required coverage percentage is met. Required for building permits in most jurisdictions with >10,000 sq ftgt;10,000 sq ft occupied floor area or fire code applicability.

Jurisdiction & Requirements
Requirements: ≥-95 dBm inbound · ≥-95 dBm outbound · ≥95% coverage
Survey Results
Worst-case measured
dBm
dBm
ft²
ft²
pts
pts
Overall Compliance
FAIL
Compliance Checklist
Inbound RSSI (-85 ≥ -95 dBm)✓ Pass
Outbound RSSI (-88 ≥ -95 dBm)✓ Pass
Area coverage (96.0% ≥ 95%)✓ Pass
Point pass rate (80.0% ≥ 95%)✗ Fail
References
NFPA 1221 §9.6 – in-building coverage requirements
IFC Section 510 – Emergency responder radio
Test method: grid-based walk test at 5 ft height
DAQ 3.0 ≈ −95 dBm for P25 digital voice