When a firefighter, police officer, or EMT’s radio goes silent inside your building, seconds can mean the difference between life and death. That’s why every ERCES (Emergency Responder Communication Enhancement System) project begins with a simple yet crucial question: where does the signal break down?
At In-Building Wireless Solutions, we answer that by mapping your building’s radio health — from the lowest parking level to the highest mechanical penthouse — using a combination of technology, fieldwork, and code-driven precision.
Step 1: The “Talk-In / Talk-Out” Reality Check
We start with calibrated radios working on your jurisdiction’s fire or law enforcement channel. Our engineers test both communication directions.
- Talk-in – can the portable radio reach the public safety repeater outside the building? (Uplink signal, radio to repeater)
- Talk-out – can dispatch hear the responder inside concrete stairwells or elevator lobbies? (Downlink signal, repeater to radio)
It’s common to have coverage good in one direction but dead in the other — especially in parking garages or elevator cores.
Step 2: Grid Testing Every 20,000 Square Feet
According to NFPA 1225 and IFC 510, buildings are divided into 20,000-square-foot grids. Within each grid, we gather signal-strength readings (RSSI in dBm) at multiple points using test radios and spectrum analyzers.
Each point is recorded, color-coded, and mapped onto the floor plans. You can literally see where radios whisper and where they shout. The result is a coverage heatmap—a dynamic blueprint of your building’s emergency communication landscape.
Step 3: Diagnosing the Dead Zones
Patterns tell the story.
- Below-grade garages usually fail due to earth attenuation.
- Stairwells lose signal due to solid concrete walls.
- Penthouse mechanical rooms frequently experience issues with metal ducting and reflective interference.
Once those patterns emerge, we model antenna placement, coax pathways, and BDA (Bi-Directional Amplifier) settings to restore the missing link.
Step 4: Data That Satisfies the AHJ
Every reading, pass/fail point, and signal contour is compiled into a report for the Authority Having Jurisdiction (AHJ). That report determines whether an ERCES is needed — and, later, whether it passes acceptance testing.
We include full metadata: radio IDs, test frequencies, timestamps, and calibration certificates. When the fire marshal asks, “How did you verify talk-in at -95 dBm?” — you’ll have the answer ready.
Why It Matters
An ERCES isn’t just a code requirement; it’s the invisible safety net supporting every first-responder entry. You won’t see the system once it’s installed — but the next time someone calls for help in your stairwell or parking level, you’ll be glad we knew exactly where the dead zones were.
In-Building Wireless Solutions, LLC
📍 Sebastopol, CA 📞 415-738-6895 🌐 www.in-buildingwireless.com
Design • Testing • Compliance for ERCES / ERRCS systems throughout California.