Nextivity SHIELD ERCES Installer, Nationwide

What SHIELD ERCES is, and why your building needs one

An ERCES — Emergency Responder Communication Enhancement System — is the in-building radio coverage system that lets fire, EMS, and police maintain reliable radio contact while operating inside your building. Modern buildings (Low-E glass, energy-efficient concrete, foil-backed insulation, lead-shielded medical wings, deep basements) routinely block 99% of the public-safety radio signal that arrives at the property line. When the fire marshal or AHJ runs an in-building DAQ (Delivered Audio Quality) survey and finds public-safety radio coverage below the local code threshold, an ERCES is triggered. NFPA 1225 (the consolidated public-safety communications standard) and IFC 510 are the model codes most AHJs adopt.

Nextivity SHIELD is the public-safety BDA (bi-directional amplifier) family JBT specifies most often. It's UL 2524 listed — the listing standard the AHJ wants — and it's the public-safety sibling of the commercial Cel-Fi line. SHIELD shares Nextivity's IntelliBoost digital amplifier core but operates on the public-safety radio frequencies (VHF, UHF, 700 / 800 MHz, P25 simulcast) instead of the cellular carrier bands. For more on JBT's broader commercial cellular Cel-Fi work, see the Cel-Fi installer page; for the model-level QUATRA active DAS scope, see the QUATRA installer page.

The SHIELD product family

SHIELD is sized by building geometry, donor signal strength, and the channelization of the host public-safety radio system. The platform spans several BDA models with different power outputs, antenna configurations, and channel selectivity:

• SHIELD T46 — high-power Class A channelized BDA for large buildings and campuses. Channel-selective filtering keeps the BDA from re-radiating noise into the host radio system; the AHJ and the radio licensee both appreciate this.
• SHIELD T36 — mid-power Class A BDA for typical mid-rise commercial, healthcare, and education.
• SHIELD T26 — lower-power Class A BDA for smaller buildings, single-floor large footprints, and parking structures.
• SHIELD passive DAS components — the matching passive coax DAS layer (donor antenna, hybrid couplers, taps, splitters, fire-rated coax, low-PIM connectors, plenum-rated downcomers) that distributes the SHIELD output through the building.
• SHIELD remote monitoring — annunciator panel and supervised monitoring of antenna VSWR, battery state, AC power, and BDA health, integrated to the fire alarm panel as UL 2524 / NFPA 1225 require.

SHIELD's channel-selective filtering matters in practice: many AHJs and public-safety radio systems (especially P25 networks) won't accept a Class B broadband BDA because of the risk of noise re-radiation into the licensed channel. Class A channelized SHIELD avoids that argument and passes AHJ review cleanly.

Code framework: NFPA 1225, IFC 510, and UL 2524

Three documents drive the ERCES code framework:

• NFPA 1225 (2022) — the consolidated standard for public-safety communications in buildings. Replaced NFPA 1221 in most jurisdictions. Defines the in-building signal-strength threshold (-95 dBm typical), the 95% / 99% area-coverage requirements, the annual test cycle, and the survivability requirements (2-hour fire-rated cable, NEMA-rated enclosure, 12 / 24-hour battery backup).
• IFC 510 — the International Fire Code chapter that AHJs reference for ERCES-triggered new construction and renovation. Most state and local fire codes adopt IFC 510 directly or by reference.
• UL 2524 — the listing standard for in-building public-safety communications systems. SHIELD T46, T36, T26 are UL 2524 listed. AHJs require UL 2524 listed equipment for ERCES, not commercial BDAs or repurposed cellular boosters.

JBT's ERCES practice is NICET-credentialed and FCC GROL-certified, and JBT files the Record of Completion (JBT-ERC-RC-001 : 2026 Edition 1.0) the AHJ requires at project close-out.

What a JBT SHIELD ERCES project looks like

A typical SHIELD ERCES deployment runs through five phases:

1. Pre-construction signal survey. A field engineer walks the building with a calibrated public-safety frequency receiver and measures the existing DAQ and signal strength on a grid. Output: an existing-conditions report the AHJ uses to scope the ERCES requirement.
2. Engineered design package + AHJ submittal. Heat-map prediction, donor-antenna study, BDA sizing, DAS layout, fire-alarm interface drawings, battery-calc, and the Record-of-Completion checklist. Submitted to the AHJ for permit.
3. Installation. Donor-antenna mounting, fire-rated 2-hour coax pathway, SHIELD BDA installation in a UL-listed NEMA enclosure with sealed lead-acid or LiFePO4 battery backup, indoor passive antenna placement on a properly-rated DAS, annunciator wiring back to the fire alarm panel, and integration to the building monitoring infrastructure.
4. Acceptance test + AHJ certification. Grid-based DAQ test on the system in service across 100% of general and critical areas. JBT performs the test in front of the AHJ inspector and produces the certified Record of Completion. The AHJ signs off; the certificate of occupancy proceeds.
5. Annual recertification. NFPA 1225 requires an annual test of the ERCES system. JBT returns annually, repeats the DAQ grid test, exercises the battery backup, verifies the supervisory loops, and re-certifies the system. The fire marshal gets the report.

Where SHIELD fits relative to other ERCES BDAs

JBT installs ERCES BDAs from multiple manufacturers — SHIELD, ADRF, Comba, Honeywell — and selects the right BDA per project. SHIELD is the right answer most of the time because of three properties: channel-selective filtering (clean AHJ approval), IntelliBoost digital regeneration (low noise re-radiation), and the matched WAVE remote-monitoring portal (proactive support before the AHJ catches an issue at annual test). For very large campuses with multiple buildings or for high-channel-count P25 simulcast systems, the BDA choice opens up; JBT engineers brief customers on the trade-offs during design.

Frequency-coordination work that matters at AHJ submittal

One detail that catches a lot of ERCES projects late in the cycle is the public-safety radio licensee coordination. SHIELD's channel-selective filtering requires JBT to know exactly which frequencies the local public-safety radio system uses — including talk-groups, conventional channels, simulcast clusters, and any P25 control channels — before we order the BDA. JBT pulls the radio frequency authorization from the relevant FCC license holder (county E-911, state EMS, fire authority) and coordinates the BDA channel plan with their radio shop. This is also the step where any pre-existing in-building amplifier or competing BDA in the same neighborhood gets documented so the AHJ doesn't discover an unauthorized noise re-radiator at acceptance test.

WAVE monitoring and post-deployment support

Every SHIELD JBT installs comes online inside the Nextivity WAVE cloud monitoring portal. WAVE gives JBT remote visibility into BDA state of health, antenna VSWR, current uplink and downlink levels, fault counters, and the battery state. JBT's nationwide ERCES support team monitors every project we've commissioned, dispatches a tech proactively when telemetry suggests a problem, and returns annually for the NFPA-required recertification. The full ERCES lifecycle — survey, design, install, commission, annual test, multi-year support — sits inside one JBT contract.

Battery backup and survivability

UL 2524 and NFPA 1225 require ERCES systems to keep operating during the same power failure that produced the emergency. SHIELD ships with secondary battery backup sized for 12 or 24 hours of standby operation depending on AHJ requirement and risk classification. JBT typically deploys sealed lead-acid batteries in a UL-listed NEMA enclosure with end-of-life monitoring, or LiFePO4 packs where the customer wants a 10-year battery service life and reduced heat output. The battery system is supervised — depleted cells, charger faults, and AC-power loss all annunciate to the fire-alarm panel under NFPA 1225 supervised-circuit requirements.

Survivability extends to the cable pathway. NFPA 1225 requires 2-hour fire-rated coax pathway from the donor antenna through to the BDA enclosure and to the most-distant indoor antenna. JBT specifies CommScope, RFS, or Andrew 2-hour-rated coax in a UL-listed pathway and documents the rating in the as-built drawings the AHJ certifies. The antenna lugs, grounding, and bonding are all installed to NEC Article 810 and 250, with documented continuity testing as part of the acceptance procedure.

Nationwide service area

SHIELD ERCES is a code-driven public-safety scope and JBT delivers it nationwide. Our home office is Kennesaw, GA; our field engineers travel to project sites across the United States. JBT carries the credentials AHJs check for: NICET certification for fire-alarm and public-safety communications, FCC GROL on the licensed-radio side, and a documented Quality Assurance program tied to NFPA 1225 and UL 2524. Whether you're a multifamily developer in Texas, a healthcare system in the Midwest, a higher-education campus in the Northeast, or a distribution-warehouse portfolio across the South, JBT scopes the project under one nationwide ERCES contract.

Atlanta-area commercial cellular work is a different service area: that's our regional Cel-Fi commercial cellular installer scope. ERCES doesn't have the same regional constraint — it's a code-driven nationwide practice.

Frequently asked questions

Call (770) 637-2094 to scope a SHIELD ERCES project anywhere in the United States, or see our ERCES / BDA service page for the full ERCES practice overview.