Glossary
BDA and ERRCS glossary
The words in your test report, permit and vendor quote, defined in plain English. Click a column header to sort. Where a term comes from a code or federal rule, we name it.
Terms
| Term | What it means | Where it comes from |
|---|---|---|
| Acceptance test | The first full test after installation, witnessed or reviewed by the fire marshal, that proves the system meets the coverage and signal rules | IFC 510.5.4; NFPA 1225 20.3.10.1 |
| AHJ (authority having jurisdiction) | The office that enforces the fire code for your building, usually the local fire marshal or fire prevention bureau | Used throughout NFPA 1225; F.S. 633.202(18) |
| Annunciator | A panel, usually in the fire command center, with labeled lights showing the BDA system's status | NFPA 1225 18.14.2 |
| Annual test | The yearly inspection and test of the whole system, with a report to the fire marshal | IFC 510.6.1; NFPA 1225 20.3.10 |
| As-built drawings | Drawings showing where every part was actually installed | IFC 510.4.2.7; NFPA 1225 20.3.10.1.3 |
| Backbone cable | The main cable or fiber that carries the signal between floors | NFPA 1225 18.12.3 |
| BDA (bi-directional amplifier) | The amplifier at the center of the system; it boosts signals both into and out of the building. The FCC calls it a signal booster | 47 CFR 90.219(a) |
| Class A signal booster | A booster that retransmits specific channels; no passband wider than 75 kHz. No FCC registration required under the current rule | 47 CFR 90.219(a); DA 14-15 |
| Class B signal booster | A booster that retransmits anything in a wide band; at least one passband wider than 75 kHz. Must be registered with the FCC | 47 CFR 90.219(a), (d)(5) |
| Consumer signal booster | A cell phone booster a carrier subscriber may use with the carrier's consent and registration; not for public safety radio | 47 CFR 20.21(a) |
| Critical areas | Places that need the highest coverage: fire command center, fire pump room, exit stairs, exit passageways, elevators, elevator lobbies, standpipe cabinets, sprinkler sectional valve locations and others the AHJ names | NFPA 1225 18.8.3 |
| DAQ (delivered audio quality) | A 1 to 5 score for how well speech comes through on a radio. NFPA 1225 and the IFC set DAQ 3.0 as the minimum | NFPA 1225 18.9, A.20.3.10 |
| DAS (distributed antenna system) | A network of antennas spread around a building and fed from one source | 47 CFR 90.219(a) |
| dBm | A unit of radio signal strength. Closer to zero is stronger; the model fire code's minimum inbound signal is -95 dBm | IFC 510.4.1.1 |
| Donor antenna | The outdoor antenna, usually on the roof, aimed at the public safety radio site | NFPA 1225 18.3.3; IFC 510.5.1 |
| Downlink | Signal from the radio system's tower to the firefighter's radio | NFPA 1225 A.18.9.1 |
| ERCES | Emergency responder communications enhancement system; the NFPA 1225 term for the whole system | NFPA 1225 chapter 18 |
| ERRCS | Emergency responder radio coverage system; another common name for the whole system | Industry usage |
| FCC Registration Number (FRN) | The ID used to log in to FCC systems, needed to register a Class B booster | DA 14-15 |
| Frequency license holder | The agency licensed by the FCC to use the radio channels the system carries, usually a county or city | 47 CFR 90.219(b); NFPA 1225 18.2.1 |
| Gain | How much the amplifier boosts the signal. Recorded at acceptance and checked every year | IFC 510.5.4 item 6; 510.6.1 item 2 |
| General building areas | Everything that is not a critical area. NFPA 1225 and IFC require 95% coverage; Miami-Dade's acceptance test uses 90% | NFPA 1225 18.8.4; IFC 510.4.1 |
| Grid test | Dividing each floor into equal areas (20 in the model code) and testing the radio at the center of each | IFC 510.5.4 |
| Industrial signal booster | Any booster that is not a consumer booster, operated with an FCC license or the licensee's consent | 47 CFR 20.21(c) |
| Isolation | How well the indoor antennas are separated, in radio terms, from the donor antenna. Must exceed system gain by at least 20 dB | NFPA 1225 18.3.3.2; IFC 510.4.2.4 |
| Level III alteration | A category of building alteration or rehabilitation defined in the Florida Building Code; in Florida it lets the fire marshal require a coverage re-test early | F.S. 633.202(18)(c)2a |
| NEMA 3R / NEMA 4 | Ratings for equipment cabinets. Batteries go in NEMA 3R or better; boosters in NEMA 4 or 4X | NFPA 1225 18.3.1 |
| Noise floor | Background radio noise. A booster must not raise it at the public safety radio site | NFPA 1225 18.9.3 |
| Oscillation | Feedback between indoor and outdoor antennas that can cut coverage or interfere with the radio system | NFPA 1225 18.3.2; IFC 510.5.4 item 7 |
| Part 90 | The part of the FCC's rules for private land mobile and public safety radio, which includes the signal booster rules | 47 CFR 90.219 |
| Passband | The range of frequencies a booster amplifies | 47 CFR 90.219(a), (d)(7) |
| Propagation delay | The tiny delay a signal picks up passing through the system; the AHJ sets a maximum | NFPA 1225 18.8.2, 18.15.4 |
| Retransmission agreement | Written consent from the frequency license holder to rebroadcast its channels | 47 CFR 90.219(b)(1)(i); F.S. 633.202(18)(d) |
| Runner service | A service contract that sends a technician to the building after a trouble signal; Miami-Dade requires a four-hour response | Miami-Dade County Code Sec. 14-69(C) |
| Secondary power | Backup power, normally a battery able to run the system 12 hours at full load | NFPA 1225 18.13.2; IFC 510.4.2.3 |
| Signal booster | The FCC term for a device that receives, amplifies and retransmits signals into and out of buildings | 47 CFR 90.219(a) |
| Supervisory signal | A message from the BDA to the fire alarm that something needs attention, such as low battery or antenna failure | NFPA 1225 18.14.1 |
| UL 2524 | The safety standard BDA system components must be listed to | NFPA 1225 18.12.1.3; IFC 510.4 |
| Uplink | Signal from the firefighter's radio back out to the tower | NFPA 1225 A.18.9.2 |
Missing a term? Tell us through the contact form and we will add it, with the date, in our changelog.
Sources
Primary documents we read for this page. Rules change; confirm with your fire marshal (AHJ).
- 47 CFR 90.219, Use of signal boosters, Electronic Code of Federal Regulations
- 47 CFR 20.21, Signal boosters, Electronic Code of Federal Regulations
- NFPA 1225, Standard for Emergency Services Communications, 2022 Edition: Chapter 18 and section 20.3.10, Georgia Office of Insurance and Safety Fire Commissioner (reproducing NFPA text)
- International Fire Code Section 510, Emergency Responder Communication Coverage, City of Eaton, Ohio (reproducing ICC model code text; edition not stated in the document)
- DA 14-15: Wireless Telecommunications Bureau Announces Availability of Part 90 Class B Signal Booster Registration Tool (Jan. 7, 2014), Federal Communications Commission
- Florida Statutes 2026, section 633.202, subsection (18), The Florida Senate
- General Guidelines for the Deployment of Two-Way Radio Communication Enhancement System (BDAs), Miami-Dade County Fire Prevention Division
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