{"product_id":"brk-9120b-hardwired-ionization-smoke-alarm","title":"BRK 9120B Hardwired Ionization Smoke Alarm — Interconnectable","description":"\u003cp\u003eThe \u003cstrong\u003eBRK 9120B hardwired ionization smoke alarm\u003c\/strong\u003e is the contractor-grade solution for new construction and hardwired residential smoke alarm replacement. A First Alert subsidiary brand engineered specifically for professional installation channels, BRK delivers the reliability and installation-ready design that electricians and building contractors depend on for residential wiring projects. The 9120B connects directly to standard 120V AC household wiring with a battery backup, and its interconnect capability ensures all alarms in the system sound simultaneously when any single unit detects smoke — the hallmark of a professional hardwired installation.\u003c\/p\u003e\n\n\u003ch2\u003eKey Features\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e120V AC hardwired power with 9V battery backup — maintains protection during power outages\u003c\/li\u003e\n  \u003cli\u003eIonization smoke detection — fast response to rapid, fast-flaming fires\u003c\/li\u003e\n  \u003cli\u003eInterconnectable — up to 18 alarms on one circuit can sound simultaneously\u003c\/li\u003e\n  \u003cli\u003eIndustry-standard quick-connect wiring harness — plug-in installation simplifies new construction and replacement\u003c\/li\u003e\n  \u003cli\u003eFront-load battery door — battery replacement without removing unit from ceiling\u003c\/li\u003e\n  \u003cli\u003eTest\/silence button — field testing and nuisance alarm suppression\u003c\/li\u003e\n  \u003cli\u003eAC power LED indicator — continuous visual confirmation of hardwired power status\u003c\/li\u003e\n  \u003cli\u003eCompatible with BRK\/First Alert series mounting brackets — direct swap for existing hardwired alarms\u003c\/li\u003e\n  \u003cli\u003eUL 217 listed — meets all residential hardwired smoke alarm requirements\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eSpecifications\u003c\/h2\u003e\n\u003ctable\u003e\n  \u003ctr\u003e\n\u003cth\u003eModel\u003c\/th\u003e\n\u003ctd\u003eBRK 9120B\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003cth\u003eSKU\u003c\/th\u003e\n\u003ctd\u003e9120B\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003cth\u003eBrand\u003c\/th\u003e\n\u003ctd\u003eBRK (First Alert Professional)\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003cth\u003ePrimary Power\u003c\/th\u003e\n\u003ctd\u003e120V AC Hardwired\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003cth\u003eBackup Power\u003c\/th\u003e\n\u003ctd\u003e9V Battery\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003cth\u003eDetection Technology\u003c\/th\u003e\n\u003ctd\u003eIonization\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003cth\u003eInterconnect\u003c\/th\u003e\n\u003ctd\u003eYes — up to 18 units\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003cth\u003eMounting\u003c\/th\u003e\n\u003ctd\u003eCeiling (standard)\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003cth\u003eApplication\u003c\/th\u003e\n\u003ctd\u003eResidential new construction, replacement hardwired\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003cth\u003eStandards\u003c\/th\u003e\n\u003ctd\u003eUL 217\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003cth\u003eWiring\u003c\/th\u003e\n\u003ctd\u003eQuick-connect plug-in wiring harness\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003eDetailed Description\u003c\/h2\u003e\n\u003cp\u003eThe BRK 9120B exists at the intersection of professional-grade reliability and residential-scale installation efficiency. BRK — a First Alert brand created specifically for the professional installation and contractor channel — builds products designed for the demands of new residential construction, multi-unit projects, and the replacement market where licensed electricians and savvy homeowners are swapping out aging hardwired alarm systems.\u003c\/p\u003e\n\n\u003cp\u003eHardwired smoke alarms represent the professional standard for residential installations because they provide continuous power from the building's electrical system rather than depending on battery condition. When AC power is present, the alarm is always powered. When AC power fails — during the power outages that often accompany severe weather events, exactly when fire risk may be elevated — the 9120B's 9V battery backup activates automatically and maintains full detection capability. This dual-power architecture is why building codes for new residential construction typically require hardwired, interconnected smoke alarms rather than battery-only units.\u003c\/p\u003e\n\n\u003cp\u003eThe interconnect capability of the 9120B is a fundamental safety advantage over single-station battery alarms. In a multi-story home, a smoke alarm sounding only at the point of origin may not be heard in a distant bedroom with the door closed. Interconnected alarms solve this problem: when the 9120B in the basement detects smoke, every connected alarm in the house — bedroom, hallway, second floor — sounds simultaneously. All occupants receive the alert regardless of their location in the building. This is the interconnect advantage that residential building codes have increasingly mandated over the past two decades.\u003c\/p\u003e\n\n\u003cp\u003eThe quick-connect wiring harness distinguishes professional-grade units from consumer models. Rather than direct wire connections that require wire nuts, the 9120B uses a plug-in connector that mates with the existing wiring harness left in place when the old alarm is removed. For contractors replacing aging hardwired systems, this design dramatically reduces installation time per unit: remove the old alarm, verify the harness is compatible, plug in the new unit, and mount. No wire stripping, no connector assembly, no junction box work required at the alarm location.\u003c\/p\u003e\n\n\u003cp\u003eThe front-load battery access door is another professional-installation detail. In finished homes with painted ceilings, removing an alarm from its mounting bracket to access a rear-mounted battery door can damage the paint or the bracket. The front-load door on the 9120B allows battery replacement with the unit still mounted — a maintenance convenience that matters across multi-unit properties where annual battery replacement is a recurring maintenance task.\u003c\/p\u003e\n\n\u003cp\u003eIonization detection technology provides rapid response to fast-flaming fires — the type of fire that spreads quickly, produces intense heat, and generates the combustion particles that ionization sensors detect most efficiently. For living areas, hallways, and locations where fast-spreading fires represent the primary risk, ionization detection provides the appropriate sensor profile. Consult with a fire safety professional about combining ionization and photoelectric alarms throughout a home for comprehensive detection coverage.\u003c\/p\u003e\n\n\u003ch2\u003eCompliance and Standards\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003eUL 217 — Single and Multiple Station Smoke Alarms\u003c\/li\u003e\n  \u003cli\u003eNFPA 72 — National Fire Alarm and Signaling Code\u003c\/li\u003e\n  \u003cli\u003eMeets IRC (International Residential Code) requirements for hardwired interconnected smoke alarms in new construction\u003c\/li\u003e\n  \u003cli\u003eMeets IFC (International Fire Code) hardwired smoke alarm requirements\u003c\/li\u003e\n  \u003cli\u003eCompatible with most residential electrical codes requiring interconnected hardwired alarms in new construction and significant renovation\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eReal-World Benefits\u003c\/h2\u003e\n\u003cp\u003eFor electrical contractors and builders, the BRK 9120B streamlines new construction rough-in and finish installation with professional wiring connections and a mounting system designed for efficient multi-unit deployment. For homeowners replacing aging hardwired alarms, the 9120B drops into existing wiring without rewiring work — connect to the existing harness, mount the bracket, and install the alarm. For property managers in buildings with hardwired infrastructure, standardizing on the 9120B provides a consistent replacement inventory that reduces service call complexity: one model covers all hardwired locations.\u003c\/p\u003e\n\n\u003ch2\u003eApplications and Use Cases\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003eNew residential construction requiring hardwired, interconnected smoke alarms per building code\u003c\/li\u003e\n  \u003cli\u003eReplacement of aging or failed hardwired smoke alarms in existing homes\u003c\/li\u003e\n  \u003cli\u003eMulti-unit residential projects where contractors need consistent, professional-grade hardwired alarms\u003c\/li\u003e\n  \u003cli\u003eRenovation projects triggering code requirement upgrades to interconnected hardwired systems\u003c\/li\u003e\n  \u003cli\u003eLandlord-initiated hardwired alarm system upgrades in rental properties\u003c\/li\u003e\n  \u003cli\u003eElectricians building alarm systems in finished basements or room additions\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eRelated Products\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\u003ca href=\"https:\/\/wcsafety.com\/collections\/fire-extinguishers\"\u003eShop All Fire Safety Products\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003eKidde 900-CUAR Hardwired Smoke and CO Alarm\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"\/products\/kidde-p3010b-photoelectric-smoke-alarm-10-year-battery\"\u003eKidde P3010B Photoelectric Smoke Alarm — 10-Year Battery\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003eKidde 30CUAR Combination Smoke and CO Alarm\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\n\n\u003ch3\u003eWhat is the difference between BRK and First Alert?\u003c\/h3\u003e\n\u003cp\u003eBRK is a brand owned by the same parent company as First Alert, operated as the professional\/contractor channel brand. BRK products are engineered for professional installation environments — electricians, builders, and contractors — and feature installation-oriented design details like quick-connect wiring harnesses. First Alert is the consumer retail brand. The core technology and safety standards are consistent across both brands.\u003c\/p\u003e\n\n\u003ch3\u003eDoes the BRK 9120B require a licensed electrician to install?\u003c\/h3\u003e\n\u003cp\u003eConnecting a smoke alarm to a 120V household circuit involves work on live electrical wiring. Most jurisdictions require this work to be performed by a licensed electrician, and building permits are typically required for hardwired alarm installation in new construction and significant renovation. Consult local building codes and permit requirements before installation. Replacement of an existing alarm using the same wiring and harness may qualify as maintenance work with different requirements — check with your local AHJ.\u003c\/p\u003e\n\n\u003ch3\u003eHow many BRK 9120B alarms can be interconnected?\u003c\/h3\u003e\n\u003cp\u003eThe BRK 9120B supports interconnection with up to 18 compatible alarms on a single interconnect circuit. When any one alarm in the interconnected system detects smoke, all interconnected units sound simultaneously. Only interconnect BRK and First Alert alarms on the same circuit — mixing brands can cause interconnect failures or false alarms.\u003c\/p\u003e\n\n\u003ch3\u003eWhat wiring is required for the BRK 9120B?\u003c\/h3\u003e\n\u003cp\u003eThe 9120B requires a 120V AC power connection (hot and neutral) plus a third wire for the interconnect signal. In new construction, this is typically a three-wire plus ground cable run to each alarm location during rough-in electrical work. For replacement installations, the existing three-wire wiring harness plugs directly into the 9120B quick-connect connector if it is a compatible BRK\/First Alert harness.\u003c\/p\u003e\n\n\u003ch3\u003eDo I still need to replace the battery in a hardwired alarm?\u003c\/h3\u003e\n\u003cp\u003eYes. The 9V backup battery in the 9120B should be replaced annually as part of routine maintenance, even though the alarm operates on AC power under normal conditions. The battery is critical for maintaining smoke detection capability during power outages — which is precisely when it must work reliably. Test the alarm monthly and replace the battery each year on a consistent schedule.\u003c\/p\u003e\n\n\u003ch3\u003eCan I use the BRK 9120B to replace a Kidde hardwired alarm?\u003c\/h3\u003e\n\u003cp\u003eThe mounting bracket footprint and wiring harness connector must be compatible. BRK and Kidde use different mounting systems and wiring harness connectors. In most replacement scenarios, you will need to replace the mounting bracket as well as the alarm unit. Check the existing wiring harness connector type before purchasing — if it is not a BRK\/First Alert compatible connector, a wiring harness adapter may be needed. Consult a licensed electrician if you are uncertain about compatibility.\u003c\/p\u003e\n\n\u003ch3\u003eIs ionization the right detection type for every room in the house?\u003c\/h3\u003e\n\u003cp\u003eIonization detection provides fast response to fast-flaming fires, making it well-suited for hallways, living areas, and locations away from cooking appliances. Near kitchens, bathrooms with showers, or in rooms where slow-smoldering fires are the primary concern, photoelectric detection may be a better fit. NFPA and fire safety professionals often recommend a combination of ionization and photoelectric alarms throughout a home for the broadest protection profile.\u003c\/p\u003e","brand":"BRK","offers":[{"title":"Default Title","offer_id":44037114560600,"sku":"9120B","price":20.98,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0594\/1900\/0920\/files\/71FMyNMOalL.jpg?v=1777171066","url":"https:\/\/wcsafety.com\/products\/brk-9120b-hardwired-ionization-smoke-alarm","provider":"WC Safety","version":"1.0","type":"link"}