+---
+title: Intrusion Detection Systems
+category: Electrical
+toc_depth: 3
+description: >
+ When to use: Electronic intrusion detection (burglar alarm) systems for commercial,
+ institutional, and industrial facilities. Covers control panels and communicators,
+ detection devices (PIR, dual-technology, glass-break, door/window contacts,
+ vibration/seismic, beam detectors), perimeter and interior protection zones,
+ local annunciation, keypad and credential arming stations, central-station signal
+ transmission, and UL-listed monitoring service. Applies to new construction and
+ major renovations across office, retail, warehouse, healthcare, education,
+ government, and critical-infrastructure project types.
+ Not intended for: Access control and credential management (see
+ [[sync/access-control-systems]]); video surveillance cameras, recorders, and VMS
+ (see [[sync/video-surveillance-systems]]); low-voltage cabling infrastructure and
+ conduit fill (see [[sync/structured-cabling]]); fire alarm initiation and signaling
+ (governed by NFPA 72 under a separate fire alarm specification); gas leak and
+ hazardous-atmosphere detection (see [[sync/gas-detection-systems]]); public safety
+ radio signal enhancement (see [[sync/public-safety-radio-systems]]); and
+ high-security SCIF or DoD-classified intrusion detection governed by ICD 705 or
+ JAFAN, which is outside commercial construction scope.
+---
+
+# Scope {toc}
+
+## This Standard covers the design, procurement, installation, testing, and maintenance of electronic intrusion detection (burglar alarm) systems for commercial, institutional, and industrial facilities. {note}
+
+## An intrusion detection system (IDS) detects unauthorized entry or attempted entry into a protected premises, annunciates the condition locally, and transmits an alarm signal to a monitoring station for response. The system comprises a control panel and communicator, detection devices arranged into supervised zones, arming stations, local annunciation, and a signal-transmission path to a central station. {note}
+
+## The Work shall include all control panels, communicators, detection devices, arming stations, annunciators, power supplies, end-of-line supervision, cabling terminations, programming, commissioning, and owner training necessary for a complete and operational system.
+
+## The system shall provide perimeter protection at the first line of entry as defined by the protection plan.
+
+## The system shall provide interior trap protection along expected intrusion paths as defined by the protection plan.
+
+## The system shall provide volumetric protection of high-value or high-risk spaces as defined by the protection plan.
+
+## Access control, video surveillance, structured cabling, fire alarm, and gas detection are coordinated with but not furnished under this Standard. {note}
+
+# Referenced Standards {toc}
+
+## Equipment, materials, and installation shall comply with the latest adopted edition of each of the following unless a specific edition is cited.
+
+## Where referenced standards conflict, the more stringent requirement shall govern unless the Engineer of Record directs otherwise in writing.
+
+## The edition of NFPA 731 enforced by the Authority Having Jurisdiction shall be confirmed before design; many jurisdictions still enforce the 2023 edition rather than the 2026 edition.
+
+| Standard | Title |
+|----------|-------|
+| NFPA 731 | Standard for the Installation of Electronic Premises Security Systems |
+| NFPA 730 | Guide for Premises Security |
+| UL 681 | Installation and Classification of Burglar and Holdup Alarm Systems |
+| UL 639 | Intrusion-Detection Units |
+| UL 634 | Connectors and Switches for Use with Burglar Alarm Systems |
+| UL 827 | Central-Station Alarm Services |
+| UL 2050 | National Industrial Security Systems |
+| NFPA 70 (NEC) Article 725 | Class 1, Class 2, and Class 3 Remote-Control, Signaling, and Power-Limited Circuits |
+| NFPA 70 (NEC) Article 760 | Fire Alarm Systems |
+| IEC 60839-11-1 | Alarm and Electronic Security Systems — Electronic Access Control Systems: System and Components Requirements |
+
+# Submittals {toc}
+
+## Action Submittals {toc}
+
+### The Contractor shall submit the following action submittals for review and approval before ordering equipment or beginning installation:
+- Product data sheets for the control panel, communicator, detection devices, arming stations, annunciators, and power supplies, with UL listings identified.
+- Shop drawings showing device locations, zone assignments, partition boundaries, mounting heights, coverage patterns, and cable routing.
+- A zone schedule listing each zone number, device type, location, partition assignment, response type (perimeter, interior, 24-hour, fire, tamper), and end-of-line resistor value.
+- A battery backup calculation per UL 681 demonstrating the required standby duration.
+- A communication path diagram showing the primary and secondary signal-transmission paths.
+- Manufacturer certification that proposed central-station monitoring is UL 827 Listed.
+
+```datasheet
+label: Action submittals required
+type: checkbox
+options:
+ - Product data (panel, devices, arming stations, power supplies)
+ - Shop drawings (device locations, coverage, routing)
+ - Zone schedule (type, partition, response type, EOLR value)
+ - Battery backup calculation (UL 681)
+ - Communication path diagram (primary + secondary)
+ - UL 827 central-station listing certification
+```
+
+## Closeout Submittals {toc}
+
+### The Contractor shall submit the following closeout submittals before final acceptance:
+- As-built drawings reflecting installed device locations, zone assignments, and cable routing.
+- The UL Certificate of Installation Completion issued to the building owner where a UL-listed system is specified.
+- Operation and maintenance manuals, including programming records and default code change procedures.
+- A commissioning report documenting walk-test results for every detection device and the central-station communication test.
+- A written maintenance and inspection schedule conforming to NFPA 731.
+- Record of owner training, including attendee list and date.
+
+```datasheet
+label: Closeout submittals required
+type: checkbox
+options:
+ - As-built drawings
+ - UL Certificate of Installation Completion
+ - Operation and maintenance manuals
+ - Commissioning / walk-test report
+ - Maintenance and inspection schedule
+ - Owner training record
+```
+
+## Informational Submittals {toc}
+
+### The Contractor shall submit the following informational submittals:
+- Installer qualifications, including UL-listing-program participation and manufacturer certification.
+- An RF site survey report where wireless zones are proposed.
+- A false-alarm management plan describing entry/exit delay optimization and user training.
+
+```datasheet
+label: Informational submittals required
+type: checkbox
+options:
+ - Installer qualifications and certifications
+ - RF site survey (wireless designs)
+ - False-alarm management plan
+```
+
+# Quality Assurance {toc}
+
+## The installing contractor shall be a licensed low-voltage / alarm contractor in the jurisdiction of the Work and shall be certified by the control-panel manufacturer.
+
+## A UL-listed installation, where specified, requires that the installing firm participate in the applicable UL listing program so the UL Certificate of Installation Completion can be issued to the owner. This certificate is frequently required by commercial property insurance carriers; its absence can void coverage assumptions even when the equipment is otherwise compliant. {note}
+
+## All detection devices shall be UL 639 Listed; door and window contacts shall additionally meet UL 634 Level II for commercial-grade tamper resistance.
+
+## The control panel and communicator shall be UL 681 Listed and classified to the specified system grade.
+
+## Where the facility is a government or defense-contractor site protecting classified or sensitive material, the system shall additionally comply with UL 2050.
+
+## A single party shall be designated responsible for the security basis of design. {note}
+
+## Where an owner engages a security consultant separate from the Engineer of Record, the consultant's basis of design and the Engineer's specification shall be reconciled in writing before bidding to avoid conflicting requirements. {note}
+
+# System Grade and Protection Level {toc}
+
+## System grade defines tamper resistance, line supervision, and monitoring-response requirements. UL Grade 2 is the commercial baseline; UL Grade 3 adds balanced/biased line supervision and tamper-evident construction for high-security applications. {note}
+
+## The system grade shall be selected to match the facility's risk and any insurance or AHJ mandate, and shall not be downgraded by substitution without Engineer approval.
+
+```datasheet
+label: System grade / protection level
+type: radio
+options:
+ - Residential / light commercial (local, single-path)
+ - Commercial UL Grade 2 (supervised, dual-path)
+ - High-security UL Grade 3 (balanced supervision, tamper-evident)
+ - UL 2050 (national industrial security)
+default: Commercial UL Grade 2 (supervised, dual-path)
+```
+
+## The protection strategy shall combine perimeter, interior, and volumetric protection as appropriate to each space.
+
+### Perimeter (first-line) protection guards doors, operable windows, and glazing at the building envelope so that an intrusion is detected at the point of entry before the intruder reaches protected assets. {note}
+
+### Interior trap protection places motion detectors along corridors, stairwells, and choke points an intruder must traverse, catching anyone who defeats the perimeter. {note}
+
+### Volumetric protection provides full-room motion coverage of vaults, server rooms, pharmacies, and other high-value spaces. {note}
+
+```datasheet
+label: Protection strategy (select all that apply)
+type: checkbox
+options:
+ - Perimeter (door/window contacts, glass-break)
+ - Interior trap (corridor and choke-point motion)
+ - Volumetric (full-room high-value spaces)
+default:
+ - Perimeter (door/window contacts, glass-break)
+ - Interior trap (corridor and choke-point motion)
+```
+
+# Control Panel and Communicator {toc}
+
+## The control panel shall provide supervised zone inputs, partition (area) management, programmable response types, event logging, and one or more communication paths to the central station.
+
+## Zone capacity shall be sized to the device count with a minimum of 25% spare zone capacity at the time of commissioning.
+
+## Panels routinely fill during phased occupancy; specifying exact device count without spare capacity forces a panel replacement or expander purchase at the first tenant fit-out. {note}
+
+```datasheet
+label: Zone capacity (control panel)
+type: radio
+options:
+ - 8 zones (small retail / tenant suite)
+ - 32 zones (medium commercial)
+ - 64 zones (large commercial)
+ - 128 zones (institutional)
+ - 256+ zones (enterprise / campus)
+default: 64 zones (large commercial)
+```
+
+```datasheet
+label: Minimum spare zone capacity at commissioning
+type: range
+unit: "%"
+min: 0
+max: 50
+step: 5
+default: 25
+```
+
+## The system shall be partitioned to isolate independently armed areas such as tenant spaces, after-hours zones, and 24-hour-protected rooms.
+
+```datasheet
+label: Number of partitions (areas)
+type: range
+unit: partitions
+min: 1
+max: 32
+step: 1
+default: 4
+```
+
+## Zone architecture shall be selected for the device density, building construction, and future expandability of the project.
+
+### Hardwired zones run a dedicated supervised conductor pair to each device; they are the most robust but require the most cable. {note}
+
+### A polling (multiplex) loop carries hundreds of supervised addressable devices over a two-conductor data loop, suited to high-rise and campus installations. {note}
+
+### Wireless RF zones use battery-powered sensors with no home-run cable, suited to retrofit where cabling is impractical, subject to an RF site survey. {note}
+
+```datasheet
+label: Zone architecture
+type: radio
+options:
+ - Hardwired (dedicated supervised pairs)
+ - Polling loop / multiplex (addressable data loop)
+ - Wireless RF (battery sensors)
+ - Hybrid (hardwired + wireless RF)
+default: Hardwired (dedicated supervised pairs)
+```
+
+# Communication and Signal Transmission {toc}
+
+## A redundant communication path is required at Grade 2 and above.
+
+## Specifying only an IP/Ethernet path leaves the system unable to report alarms during a network or ISP outage. {note}
+
+## The communicator shall provide dual-path signal transmission consisting of a primary IP path and a secondary cellular path for UL Listed Grade 2 and higher installations.
+
+## The primary IP path shall use TLS-encrypted transmission to the central station.
+
+## The maximum signal-transmission time from alarm to central-station receipt shall not exceed 60 seconds per UL 827.
+
+## The communication paths shall be supervised, and loss of any path shall be reported as a trouble condition.
+
+```datasheet
+label: Communication path configuration
+type: radio
+options:
+ - Single-path IP (TLS)
+ - Dual-path IP + cellular LTE
+ - Dual-path IP + long-range radio
+ - Triple-path IP + cellular + radio (critical-infrastructure only)
+default: Dual-path IP + cellular LTE
+```
+
+```datasheet
+label: Maximum signal transmission time to central station
+type: range
+unit: s
+min: 15
+max: 90
+step: 15
+default: 60
+```
+
+# Detection Devices {toc}
+
+## Detection technology shall be matched to each space's geometry, environmental conditions, and false-alarm tolerance.
+
+## Dual-technology detection shall be provided in spaces subject to thermal disturbance from HVAC hot-air diffusers, skylights, or large sun-loaded windows.
+
+## Specifying passive-infrared (PIR) detectors alone in those conditions causes thermal masking, producing false alarms or missed detections. {note}
+
+## Passive-infrared detectors shall be provided for general interior trap and volumetric coverage in thermally stable spaces.
+
+```datasheet
+label: PIR detector coverage pattern
+type: radio
+options:
+ - 35×35 ft standard interior
+ - 40×40 ft ceiling-mount wide-angle
+ - Curtain (15°–20° narrow, perimeter window)
+default: 35×35 ft standard interior
+```
+
+```datasheet
+label: PIR mounting height
+type: range
+unit: ft
+min: 6
+max: 9
+step: 0.5
+default: 8
+```
+
+## Dual-technology detectors combining PIR and microwave with AND logic shall be provided in spaces subject to thermal disturbance, drafts, or high false-alarm cost.
+
+### Dual-technology detectors require both the infrared and microwave channels to trigger simultaneously before declaring an alarm, sharply reducing nuisance trips from a single environmental cause. {note}
+
+## Glass-break detectors shall be provided wherever glazing larger than 9 sq ft exists at grade.
+
+### Relying on door contacts alone leaves large storefront and curtain-wall glazing unprotected; an intruder can breach the glass without ever opening a contacted door. {note}
+
+```datasheet
+label: Glass-break detector coverage radius
+type: range
+unit: ft
+min: 15
+max: 25
+step: 5
+default: 25
+```
+
+## Door and window contacts shall be UL 634 Listed and selected for surface or recessed mounting per the door and frame type.
+
+### High-security (Grade 3) openings shall use balanced magnetic switches that detect external magnet defeat attempts rather than plain reed contacts.
+
+```datasheet
+label: Door/window contact type
+type: radio
+options:
+ - Surface-mount reed contact
+ - Recessed reed contact
+ - Balanced magnetic switch (high-security)
+ - Overhead/roll-up door contact
+default: Surface-mount reed contact
+```
+
+## Vibration / seismic detectors shall be provided on vault walls, ATM enclosures, and safe rooms where forced-entry attack on the structure is a credible threat.
+
+## Photoelectric beam detectors may be provided across long perimeter spans, fence lines, or large openings where point sensors are impractical.
+
+# Zone Supervision and Tamper Protection {toc}
+
+## Every zone shall be supervised with an end-of-line resistor (EOLR) so that an open (cut) or shorted conductor is reported as a distinct trouble condition rather than ignored.
+
+## EOLR values differ between panel manufacturers; omitting the specified value lets a substituted contractor install a mismatched resistor, producing nuisance zone faults that are mistaken for device failures. {note}
+
+## The end-of-line resistor value shall be specified and shall match the control panel's supervision requirement.
+
+```datasheet
+label: End-of-line resistor (EOLR) value
+type: radio
+options:
+ - "1 kΩ"
+ - "2.2 kΩ"
+ - "4.7 kΩ"
+ - Dual EOL (alarm + tamper)
+default: "2.2 kΩ"
+```
+
+## All enclosures, including the control panel, power supply, annunciators, and exterior-mounted devices, shall be fitted with tamper switches reporting cover removal.
+
+## Exterior devices shall be tamper-supervised.
+
+## Exterior-mounted sounders, beams, and contacts without tamper supervision are a common UL 681 inspection deficiency. {note}
+
+## Line-cut and line-short detection shall be active on all supervised zones at all times, including when the partition is disarmed.
+
+# Power Supply and Backup {toc}
+
+## The intrusion control panel shall be powered from a dedicated 120V AC branch circuit and shall not share AC power with fire alarm or emergency power circuits without documented coordination.
+
+## Sharing intrusion AC power with a fire alarm panel or generator-backed circuit creates cross-system fault propagation and complicates code compliance; coordinate the dedicated branch circuit with the electrical engineer early. See [[sync/electrical-service-entrance]]. {note}
+
+## Secondary battery backup shall maintain full system operation for the specified standby duration, with a minimum of 4 hours per NFPA 731.
+
+## High-security applications shall provide secondary battery backup for a minimum standby duration of 24 hours.
+
+## Standby duration should be matched to facility criticality where extended power loss is credible.
+
+## A 4-hour battery satisfies code but may be inadequate for higher-criticality facilities. {note}
+
+```datasheet
+label: Secondary battery standby duration
+type: radio
+options:
+ - 4 hours (code minimum)
+ - 8 hours (commercial default)
+ - 24 hours (high-security / critical)
+default: 8 hours (commercial default)
+```
+
+## The battery shall be sized per UL 681 from quiescent current times standby hours plus alarm current times alarm duration, and the sealed lead-acid capacity shall be selected accordingly.
+
+```datasheet
+label: Standby battery capacity (sealed lead-acid)
+type: select
+unit: Ah
+options:
+ - "7"
+ - "12"
+ - "18"
+ - "26"
+default: "12"
+```
+
+## Low-battery and AC-loss conditions shall be supervised and reported to the central station as supervisory signals.
+
+# Arming Stations {toc}
+
+## Arming stations shall allow authorized users to arm and disarm each partition and shall display zone and trouble status.
+
+## At least one arming station shall be located at each primary entrance serving a partition, positioned within the entry-delay path.
+
+```datasheet
+label: Arming station type
+type: radio
+options:
+ - Numeric keypad
+ - Touchscreen keypad
+ - Keypad + proximity reader hybrid
+ - Wireless keyfob (supplementary)
+default: Numeric keypad
+```
+
+## Entry and exit delays shall be programmed to allow authorized users to reach an arming station without triggering an alarm while minimizing the window available to an intruder.
+
+```datasheet
+label: Entry delay
+type: range
+unit: s
+min: 30
+max: 60
+step: 15
+default: 30
+```
+
+```datasheet
+label: Exit delay
+type: range
+unit: s
+min: 45
+max: 90
+step: 15
+default: 60
+```
+
+# Annunciation {toc}
+
+## Local annunciation shall sound an audible alarm and, where required, a visual strobe upon an unacknowledged intrusion condition.
+
+## Interior sounders shall produce a minimum of 85 dBA at 10 ft.
+
+## Exterior weatherproof bells or sirens, where provided, shall produce a minimum of 90 dBA and shall be tamper-supervised.
+
+## ADA-compliant strobes shall be provided where visual notification is required for accessibility.
+
+```datasheet
+label: Annunciation configuration
+type: radio
+options:
+ - Local sounder/strobe only
+ - Local + central-station reporting
+ - Local + central station + direct police connect
+default: Local + central-station reporting
+```
+
+```datasheet
+label: Interior sounder output
+type: range
+unit: dBA at 10 ft
+min: 85
+max: 110
+step: 5
+default: 85
+```
+
+# Central-Station Monitoring {toc}
+
+## The UL 827 listing requirement for the monitoring central station shall be stated explicitly in the contract documents.
+
+## Specifying a system as "monitored" without mandating a UL 827 listing permits lower-tier monitoring that may fail insurance or AHJ requirements. {note}
+
+## Monitoring shall be provided by a UL 827 Listed central station unless proprietary owner-operated monitoring meeting equivalent staffing and redundancy is approved in writing.
+
+## The central station shall acknowledge and act on received alarms within the response-time service level established for the facility.
+
+## Verified-alarm protocol using video or audio cross-verification should be specified where the jurisdiction requires verification before police dispatch.
+
+```datasheet
+label: Monitoring service
+type: radio
+options:
+ - UL 827 Listed central station
+ - Proprietary (owner-operated) monitoring
+ - Self-monitoring (app notification)
+default: UL 827 Listed central station
+```
+
+```datasheet
+label: Central-station alarm response time (SLA)
+type: select
+unit: s
+options:
+ - "30"
+ - "60"
+ - "90"
+ - "120"
+default: "60"
+```
+
+# Integration with Other Systems {toc}
+
+## The integration between the intrusion detection system and access control or video surveillance shall be defined in the contract documents.
+
+## Omitting the "secure all doors on alarm" relay between intrusion and access control causes RFIs and change orders when the two systems are supplied by different vendors. {note}
+
+## The control panel shall provide programmable output relays for integration with access control and video surveillance, including alarm-triggered door securing and camera-call-up. See [[sync/access-control-systems]] and [[sync/video-surveillance-systems]].
+
+## Alarm events should be correlated with recorded video at the head-end to support alarm verification and post-event review.
+
+```datasheet
+label: System integration scope (select all that apply)
+type: checkbox
+options:
+ - Access control output relay (secure-on-alarm)
+ - Video surveillance camera call-up / correlation
+ - Building automation after-hours signaling
+ - Unified security head-end
+default:
+ - Access control output relay (secure-on-alarm)
+ - Video surveillance camera call-up / correlation
+```
+
+# Wiring and Raceway {toc}
+
+## Intrusion detection wiring shall be installed as Class 2 power-limited circuit per NEC Article 725, with Class 3 permitted only for higher-voltage notification circuits.
+
+## Intrusion wiring routing shall be coordinated with the electrical engineer before rough-in.
+
+## Running intrusion conductors in the same conduit as power wiring violates NEC Article 725 separation. {note}
+
+## Intrusion wiring shall not share a raceway with power conductors and shall maintain the separation required by NEC Article 725.
+
+## Conduit fill shall not exceed 40% per NEC Article 725 and standard low-voltage practice.
+
+## Plenum-rated (CMP) cable shall be provided where required by NEC Article 725 and the building occupancy. Detailed low-voltage cable scheduling is governed by [[sync/structured-cabling]]. {note}
+
+```datasheet
+label: Zone and keypad cable
+type: radio
+options:
+ - 22 AWG / 4-conductor, unshielded
+ - 22 AWG / 4-conductor, shielded (EMI-prone)
+ - 22 AWG / 6-conductor, unshielded
+ - Plenum-rated (CMP), 22 AWG / 4-conductor
+default: 22 AWG / 4-conductor, unshielded
+```
+
+## Motion detectors located near EMI sources shall be wired with shielded cable, grounded at one end only.
+
+## Device locations, cable routing, and pathway extents shall be coordinated to the security drawings [[drawing: device and routing plan]].
+
+# Testing and Commissioning {toc}
+
+## Every detection device shall be walk-tested at commissioning to confirm coverage, zone assignment, and reporting before acceptance.
+
+## A full point-to-point test shall verify that each zone annunciates correctly at the keypad and at the central station with correct zone identification.
+
+## Tamper, line-cut, and line-short conditions shall be induced on a representative sample to confirm supervision reporting.
+
+## A central-station communication test shall confirm signal receipt on every communication path within the required transmission time.
+
+## Entry and exit delays shall be verified against the programmed values for each partition.
+
+```datasheet
+label: Commissioning tests (select all that apply)
+type: checkbox
+options:
+ - Walk-test every detection device
+ - Point-to-point zone annunciation test
+ - Tamper / line-cut / line-short supervision test
+ - Central-station communication test (all paths)
+ - Entry/exit delay verification
+default:
+ - Walk-test every detection device
+ - Point-to-point zone annunciation test
+ - Tamper / line-cut / line-short supervision test
+ - Central-station communication test (all paths)
+ - Entry/exit delay verification
+```
+
+# False-Alarm Management {toc}
+
+## Without an owner protocol for delay optimization and user training, false-alarm rates exceed jurisdictional thresholds, triggering fines and, in some jurisdictions, loss of police response. {note}
+
+## The false-alarm rate shall not exceed 1 per 30-day period per partition; exceeding this threshold shall trigger a mandatory technical evaluation.
+
+## The Contractor shall deliver a false-alarm management plan and shall train owner personnel on correct arming, disarming, and delay use.
+
+```datasheet
+label: False-alarm threshold (per partition)
+type: range
+unit: events / 30 days
+min: 1
+max: 5
+step: 1
+default: 1
+```
+
+# Maintenance and Inspection {toc}
+
+## The system shall be inspected and tested on a recurring schedule conforming to NFPA 731, including battery condition and device function.
+
+## Detection devices shall be walk-tested at each periodic inspection at a frequency of not less than annually, and semi-annually for high-security installations.
+
+## An automatic supervisory communication test shall be transmitted to the central station not less than monthly to confirm path integrity.
+
+```datasheet
+label: Periodic inspection / walk-test frequency
+type: radio
+options:
+ - Annual
+ - Semi-annual
+ - Quarterly
+default: Annual
+```
+
+```datasheet
+label: Automatic supervisory signal interval
+type: radio
+options:
+ - Daily
+ - Weekly
+ - Monthly
+default: Monthly
+```
+
+# Warranty {toc}
+
+## The Contractor shall warrant the complete intrusion detection system against defects in materials and workmanship for a period of not less than one year from the date of Substantial Completion.
+
+## The warranty shall include parts, labor, and reprogramming necessary to correct covered defects.
+
+## Manufacturer warranties on control panels and detection devices shall be assigned to the Owner where they extend beyond the contractor warranty period.
+
+```datasheet
+label: System warranty period
+type: radio
+options:
+ - 1 year
+ - 2 years
+ - 3 years
+default: 2 years
+```
+
+# Spare Parts {toc}
+
+## The Contractor shall furnish spare parts to support continued operation between the warranty period and routine resupply.
+
+### The Contractor shall furnish the following spare parts to the Owner at closeout:
+- Spare detection devices of each type installed, at not less than 2% of the installed quantity (minimum one of each type).
+- One spare standby battery of each capacity installed.
+- A quantity of end-of-line resistors of each value used sufficient for field service.
+
+```datasheet
+label: Spare detection devices (% of installed, each type)
+type: range
+unit: "%"
+min: 0
+max: 10
+step: 1
+default: 2
+```