← All reports
PDF Excel ReqIF

Smart Building Management System

Concept of Operations (ConOps) — ISO/IEC/IEEE 15289 — Description | IEEE 29148 §6.1
Generated 2026-03-27 — UHT Journal / universalhex.org

Mission Statement

The Smart Building Management System exists to maintain safe, comfortable, and energy-efficient indoor environments for occupants of a large commercial office building while providing integrated control of HVAC, lighting, fire safety, and access control subsystems. Without this system, building operations would rely on fragmented manual controls, resulting in energy waste of 20-40%, degraded occupant comfort, delayed emergency response, and inability to meet modern energy performance regulations (EN 15232 Class A). The operational driver is reducing whole-life building operating costs while meeting net-zero carbon targets and ensuring life-safety compliance.

Stakeholders

StakeholderRelationshipHex Code
Facility Manager primary operator, monitors dashboard, responds to alarms, manages energy targets, coordinates maintenance (from Normal Operation, Degraded, Maintenance scenarios) 010D5AF9
Building Occupant 2000+ office workers, expects 21-23°C/40-60% RH/500 lux, interacts via badge and comfort app, includes vulnerable individuals (from all operational scenarios) 000C4289
HVAC Maintenance Contractor quarterly preventive + on-call corrective, requires BMS maintenance access, F-Gas certified (from Maintenance scenario) 00843AF8
Fire Safety Officer responsible person under Fire Safety Order 2005, approves fire mode logic, conducts weekly tests, coordinates fire risk assessments (from Fire Emergency scenario) 018D7AF9
Building Owner/Energy Manager sets net-zero targets, approves capex, reviews energy reports, concerned with EN 15232 Class A and EPC rating (from Demand Response scenario)
Security Operations Centre 24/7 monitoring, validates visitor access, responds to security alarms, manages after-hours restricted mode (from Unoccupied Setback scenario)

Operating Modes

ModeDescription
Normal Operation occupancy >5% AND all subsystems nominal → HVAC 21-23°C/40-60% RH, daylight harvesting, demand response → exit on low occupancy or fault
Fire Emergency confirmed alarm (two-detector or MCP) → HVAC shutdown, smoke extraction, stairwell pressurisation, doors fail-open, lifts recalled, fire service notified → exit on brigade all-clear + panel reset
Unoccupied Setback occupancy <5% for 30min → HVAC 16-28°C, emergency lighting only, restricted access → exit on first badge-in after 05:30
Degraded Operation non-safety subsystem fault → local standalone control, reduced optimisation, alarm raised → exit when fault cleared
Startup/Commissioning power restoration → sequential energisation (fire→access→HVAC→lighting), self-test, purge → exit when zones within 2°C
Maintenance authorised request → zone/subsystem offline, safety interlocks active, overrides logged → exit when returned to auto

Operational Scenarios

Monday morning warm-up

05:30 BMS exits Setback, pre-occupancy purge, sequential HVAC warm-up, lighting follows cleaning crew. By 08:00 full occupancy, demand-responsive optimisation active. Happy path demonstrating startup-to-normal transition.

Floor fire during occupied hours

14:30 smoke detected floor 12, coincidence logic confirms in 15s, HVAC shutdown + smoke extraction + stairwell pressurisation in 30s, doors release, 2000 evacuated, fire service in 8min, all-clear at 45min, re-occupancy via Startup mode.

BACnet trunk failure

construction severs trunk to floors 15-17, 45 VAV + 12 AHU controllers lost, alarm to FM, controllers revert to standalone, fire systems unaffected (separate loop), 4-hour repair, occupants see ±2°C drift.

Summer heatwave demand response

38°C outdoor, grid operator requests 20% load cut via OpenADR, BMS pre-cools then raises setpoints 2°C, dims perimeter lighting, shifts DHW/EV loads. FM approves. Compliance confirmed, DR credit earned.

Quarterly HVAC maintenance

Saturday 06:00, tech logs in, isolates AHU-03 (floors 7-9), BMS compensates via adjacent AHUs, filter replacement + coil cleaning + sensor calibration (±0.5°C/±3% RH), return to auto, self-test, compliance log generated.

Operating Environment & Constraints

CategoryConstraint
Physical 50,000 sqm, 20+ floors, temperate maritime climate UK, -5°C to 38°C ambient, dual 11kV supply + diesel standby
Indoor 21-25°C (season-dependent), 40-60% RH, 500 lux office, CO2 <1000 ppm, noise <40 dB(A)
Regulatory EN 15232 Class A, BS 5839-1 Cat L1, BS 7671 18th Ed, Fire Safety Order 2005, Building Regs Part L, HSE ACOP L8, GDPR, BS EN 50131
Network BACnet/IP backbone on dedicated OT VLAN, Modbus RTU/TCP for legacy devices, cloud analytics via secured API gateway, cybersecurity per IEC 62443

External Interfaces

SystemInterfaceHex Code
Utility Grid 11kV/400V supply, smart meter for consumption data, OpenADR 2.0b for demand response signals. Owned by DNO. 99.9% availability. 54B77A59
Local Fire and Rescue Service monitored fire alarm via BS 5979 ARC, dual-path signalling, one-way alarm transmission with zone location. 8-min response. 99.99% availability. 40E57A58
Cloud Analytics Platform secured API gateway (TLS 1.3), receives sensor data for ML-based optimisation, returns setpoint recommendations. Owned by BMS vendor. Degraded operation possible without cloud.
Corporate IT Network firewall-segregated interface for occupancy data from room booking system, visitor management, and HR badge provisioning. GDPR compliance required. Owned by tenant IT department.