Nexus — Use Case: AER Equipment Register

Section 01 -- Overview [M]

Field	Value
Use Case ID	UC-P1
Client Reference [M]	AER Project -- Oil & Gas capital project equipment management
System Name [M]	Augmented Equipment Register (AER)
Domain [M]	Oil & Gas / Industrial Engineering -- Equipment Data Management
One-Line Description [M]	Centralized equipment registration, CFIHOS/NORSOK tag classification, multi-discipline approval workflows, maturity scoring, and EDR data consolidation integration
Status [M]	Planned -- Requirements documented, 0% implemented
Target Delivery [M]	TBD -- pending resource allocation and CFIHOS licensing

Summary [M]

The Augmented Equipment Register manages the full lifecycle of industrial equipment data for capital projects in the oil and gas sector. Equipment items are registered, classified against CFIHOS v2.0 and NORSOK standards, tagged with auto-generated identifiers, enriched with discipline-specific properties, scored for data maturity, and approved through a multi-stage workflow before being issued as controlled deliverables.

The system integrates bi-directionally with the Enhanced Data Repository (EDR v6) for data consolidation. AER is the authoritative master for equipment data; EDR is the consolidation target. All data exchanges are logged in a full audit trail with conflict resolution rules.

Nexus orchestrates the approval pipeline: Engineer data entry, Engineering Lead discipline review, Collator final review, and Issue. ChameleonV2 renders role-specific form variants (Engineers see discipline-filtered field blocks; Collators see maturity summaries and override controls).

Section 02 -- Actors [M]

Role [M]	Description [M]	Access Level [D]	Frequency [D]
Engineer	Data entry within discipline-assigned field blocks (PROC, MECH, ELEC, INST, SAFE, PIPE). Generates tags, maps equipment relationships.	Write own discipline fields, read all. Submit for review.	Daily -- primary data producers
Engineering Lead	Discipline-level technical review and approval of engineer work. Validates data quality within their discipline.	Approve/reject within discipline. Read all.	Daily -- reviews engineer submissions
Collator	Final deliverable review across all disciplines. Can override maturity scoring thresholds with justification. Issues controlled deliverables.	Read/approve all disciplines. Override maturity. Issue control.	Weekly -- batch deliverable review cycles
Data Steward	System configuration: standards management, validation rules, maturity scoring configuration, EDR field mapping definitions.	System config. No data approval authority.	Periodic -- configuration changes
Manager	Reporting and oversight. Views dashboards, KPIs, and audit reports across all disciplines.	Read-only all data. Dashboard and report access.	Weekly -- oversight and reporting
Administrator	System-wide management: user accounts, roles, permissions, audit log access, system health monitoring.	Full system access. User management. Audit logs.	As needed -- user admin and troubleshooting

Permission Model [M]

Engineering discipline permissions follow a "grant trumps deny" model -- if a user has write access to multiple disciplines, the highest permission level across those disciplines applies. Six engineering disciplines are defined: PROC (Process), MECH (Mechanical), ELEC (Electrical), INST (Instrumentation & Control), SAFE (Safety Systems), PIPE (Piping).

Section 03 -- User Stories [M/D]

35 user stories across 6 epics. Sourced from archive/AER/docs/html/USER_STORY_REGISTER.html.

Actor: Engineer

P1 [M]: ER-001 -- Register new equipment with form, type dropdown, and unique ID generation
P1 [M]: ER-002 -- Update equipment details with full audit trail
P1 [M]: TM-001 -- Auto-generate tags per CFIHOS/NORSOK rules, validated for uniqueness
P1 [M]: PM-001 -- Add/update property values with type validation and UoM enforcement
P2 [D]: ER-003 -- Change equipment status (active/maintenance/decommissioned) with notifications
P2 [D]: ER-004 -- Define equipment relationships (parent-child, connected-to)
P2 [D]: TM-002 -- Manual tag entry/override with compliance warnings
P2 [D]: PM-005 -- Bulk update property values across multiple equipment

Actor: Data Steward

P1 [M]: ER-005 -- Define equipment types with inheritable property sets
P1 [M]: PM-002 -- Define property definitions (data types, validation rules, UoM, categories)
P1 [M]: SI-001 -- Configure EDR integration (connection, auth, sync frequency, scope)
P1 [M]: SI-002 -- Map fields between AER and EDR with transformation rules
P2 [D]: TM-003 -- Define/update tag generation rules per standard with versioning
P2 [D]: SI-004 -- Define conflict resolution rules (authoritative system per field)

Actor: Manager

P1 [M]: SR-001 -- Search equipment by tag/property/type/status with saved criteria
P2 [D]: SR-002 -- Generate reports by type/status/location with charts and exports
P2 [D]: SR-003 -- Export data to CSV/Excel/JSON
P2 [D]: SR-005 -- Dashboard with configurable KPI widgets

Actor: Administrator

P1 [M]: UM-001 -- Create/manage user accounts (CRUD, activation, password reset)
P1 [M]: UM-002 -- Define roles and permissions with immediate effect
P2 [D]: UM-003 -- SSO with corporate identity provider
P2 [D]: UM-004 -- Audit logs of user actions with filtering and export
P2 [D]: SI-003 -- Monitor EDR sync status/errors with alerts and historical trends
P2 [D]: SI-005 -- RESTful API for external access with OpenAPI docs

Section 04 -- System Flows [M/D]

Flow: Equipment Registration and Approval [M]

Trigger [M]: Engineer initiates new equipment registration via ChameleonV2 form.

#	Step [M]	Actor [M]	Input [M]	Output [D]	Decision [M]
1	Create equipment record	Engineer	Equipment type, name, discipline fields	Draft entity with UUID	--
2	Auto-generate tag	System	Equipment type + CFIHOS rules	CFIHOS/NORSOK compliant tag	Uniqueness check pass/fail
3	Assign properties	Engineer	Property values per type definition	Validated property set	Type/range/UoM validation
4	Calculate maturity score	System	Property completion + validation status	Maturity percentage	Threshold met for review?
5	Submit for discipline review	Engineer	Complete equipment record	Status: In Review	--
6	Discipline review	Engineering Lead	Equipment record + maturity score	Approve / Reject / Request Changes	HUMAN GATE -- discipline approval
7	Batch for deliverable	System	Approved items	Deliverable batch	--
8	Final deliverable review	Collator	Batch of approved items	Issue / Reject / Override maturity	HUMAN GATE -- final approval
9	Issue deliverable	System	Approved batch	Status: Issued. Audit record.	--

Result [M]: Equipment item progresses from Draft through In Review, Approved, Batched, to Issued status with full audit trail.

Exceptions [D]: Rejection at step 6 returns item to Engineer with comments. Rejection at step 8 returns batch to Engineering Lead. Collator can override maturity threshold with logged justification.

SLA [D]: Engineering Lead review: 5 business days (escalates to Engineering Manager). Collator review: 3 business days (escalates to Deliverable Owner).

Volume [M]: [AWAITING CLIENT CONFIRMATION] -- expected 100+ concurrent users, batch sizes TBD.

Flow: EDR Data Synchronization [M]

Trigger [M]: Scheduled (every 15 min batch), event-driven (real-time critical updates), or manual (user-initiated).

#	Step [M]	Actor [M]	Input [M]	Output [D]	Decision [M]
1	Detect change set	System	Equipment records modified since last sync	Change manifest	--
2	Apply field mapping	System	AER fields + mapping rules	EDR-compatible payload	Transformation success/failure
3	Conflict detection	System	AER payload vs EDR current state	Conflict report	Auto-resolve per rules or flag for manual
4	Push to EDR	System	Resolved payload	EDR acknowledgement + reference IDs	Success / retry / fail
5	Log audit trail	System	Sync result	Audit record with timestamps, reference IDs	--

Result [M]: AER equipment data synchronized to EDR with full audit trail. AER is authoritative; all override decisions logged.

SLA [D]: Real-time sync: < 5 seconds. Batch sync: every 15 minutes, up to 10,000 records per batch.

Section 05 -- Data Model [M/D]

Entities

Entity [M]	Description [M]	Key Fields [M]	States [D]	Relationships [D]
Equipment	A registered physical equipment item	equipment_id (UUID PK), name, description, equipment_type_id (FK), status, created_at/by, updated_at/by	Draft, In Review, Approved, Batched, Issued, Archived	belongs_to EquipmentType, has_many Tags, has_many Properties, has_many Relationships
Equipment Type	Classification defining inheritable property sets	equipment_type_id (UUID PK), name, code, description, parent_type_id (self-FK)	Active, Deprecated	self-referential hierarchy (parent-child types)
Tag	CFIHOS/NORSOK compliant identifier for equipment	tag_id (UUID PK), tag_value, equipment_id (FK), tag_standard_id (FK), status, is_primary	Active, Superseded, Retired	belongs_to Equipment, references TagStandard
Tag Standard	Generation rules for a tagging standard (CFIHOS, NORSOK)	tag_standard_id (UUID PK), name, code, format_pattern, version	Active, Archived	has_many Tags
Property	A data value attached to equipment (typed, validated)	property_id (UUID PK), equipment_id (FK), property_def_id (FK), value (TEXT), last_updated	Current, Historical (versioned)	belongs_to Equipment, references PropertyDefinition
Property Definition	Schema for a property (type, validation, UoM)	property_def_id (UUID PK), name, data_type, unit_of_measure, required, validation_rule	Active, Deprecated	belongs_to EquipmentType (inheritable)
Equipment Relationship	Link between two equipment items (parent-child, connected-to, etc.)	relationship_id (UUID PK), source_equip_id (FK), target_equip_id (FK), relationship_type	Active, Dissolved	references Equipment (source + target)
EDR Integration Record	Sync state tracking per equipment item	integration_id (UUID PK), equipment_id (FK), edr_reference_id, last_sync, sync_status	Synced, Pending, Conflict, Error	belongs_to Equipment

Business Rules [M/D]

ID	Rule [M]	Trigger [D]	On Violation [D]
BR-01	Tags must be unique within a standard across all equipment	On tag generation or manual entry	Block save, display conflict
BR-02	Equipment must meet maturity threshold before review submission	On submit for review	Block submission, show missing fields
BR-03	Property values must conform to defined data_type and unit_of_measure	On property value save	Reject value with type error message
BR-04	CFIHOS compliance: standard equipment types must use CFIHOS v2.0 classification codes	On equipment type assignment	Warning for custom types; compliance flag set
BR-05	AER is authoritative source for equipment data in EDR sync conflicts	On sync conflict detection	AER value wins by default; override logged in audit
BR-06	Engineers can only edit fields within their assigned discipline(s)	On any field edit	Block edit, permission denied
BR-07	Collator maturity override requires written justification	On maturity threshold override	Justification field required; logged in audit

Section 06 -- Screens [D]

Screen [D]	Actor [M]	Purpose [D]	Key Elements [D]
Equipment Register	Engineer, Manager	Browse, search, filter all equipment	Data table with tag/type/status columns, search bar, saved filter presets, export button
Equipment Detail / Edit	Engineer	View and edit equipment record	Discipline-filtered field blocks, tag display, property grid, relationship map, maturity indicator
Discipline Review Queue	Engineering Lead	Review pending submissions within discipline	Queue list with maturity scores, diff view vs previous version, approve/reject/comment actions
Deliverable Batch Review	Collator	Review and issue batched deliverables	Batch list, per-item maturity summary, override controls with justification field, issue action
Tag Management	Data Steward	Configure tag standards and generation rules	Standard selector, format pattern editor, rule version history, compliance stats
EDR Integration Dashboard	Administrator, Data Steward	Monitor sync health and resolve conflicts	Sync status timeline, error log, conflict queue, field mapping editor, manual sync trigger
Management Dashboard	Manager	KPIs and operational oversight	Equipment count by status/type/discipline, maturity distribution, approval cycle times, EDR sync health
User Administration	Administrator	Manage users, roles, permissions	User list, role assignment, discipline permissions, audit log viewer

Section 07 -- Integrations [M]

System [M]	Direction [M]	Data [M]	Format [D]	Frequency [M]	Fallback [D]
EDR v6 (Enhanced Data Repository)	Both (AER master)	Equipment records, properties, tags, classification codes, consolidation status	REST API (JSON), OAuth 2.0 Client Credentials	Real-time (<5s for critical), Batch (15 min), On-demand (manual)	Queue failed messages in Redis, retry with exponential backoff, alert on 3+ failures
Corporate Identity Provider	In	User authentication, SSO tokens, group memberships	SAML 2.0 / OAuth 2.0	On login	Local credential fallback with MFA
CFIHOS Reference Data Library	In	Equipment classification codes, standard property definitions, tag format rules	Import (structured data load)	On standard version update	Operate on cached version until update confirmed

Section 08 -- Infrastructure [D]

Layer	Choice [D]	Reason [D]
Hosting	Containerized (Docker/Kubernetes) -- client cloud or on-prem	Client environments vary; container portability required
Backend	Node.js + Express.js (microservices)	Matches existing AER architecture decision; async I/O for integration layer
Database	PostgreSQL (primary) + Redis (message queue/cache)	Relational model for equipment data; Redis for sync queue and session cache
Frontend	ChameleonV2 (Nexus pipeline-driven rendering)	Role-variant forms, no bespoke frontend per workflow change
API	OpenAPI 3.0, REST	Industry standard; enables third-party integration
Auth	OAuth 2.0 + RBAC (6-role hierarchy)	SSO integration requirement; discipline-level permissions

Constraints [M]

Data residency: [AWAITING CLIENT CONFIRMATION] -- client may require on-prem or regional cloud
Mandated standards: CFIHOS v2.0 compliance mandatory for standard equipment types
Capacity: 100+ concurrent users (load testing required before production)

Environments [D]

Environment	Purpose
Development	Build and unit test
Integration	EDR connectivity testing with real sync
UAT	Client acceptance testing
Production	Live operational use

Section 09 -- Critical Path [D]

#	Item [D]	Depends On	Duration [D]	Blocker Risk [D]
1	CFIHOS v2.0 licensing and documentation access	--	External dependency	HIGH -- cannot implement tag engine without specs
2	Data model implementation (Equipment, Type, Tag, Property entities)	#1	3 weeks	Low
3	Workflow engine (approval pipeline with RBAC gates)	#2	2 weeks	Low -- Nexus pipeline patterns proven
4	Tag generation engine (CFIHOS + NORSOK rule application)	#1, #2	2 weeks	MEDIUM -- complexity of CFIHOS format rules
5	EDR Integration Gateway (sync, conflict resolution, audit)	#2, EDR v6 production environment access	3 weeks	HIGH -- requires EDR production access (D-002)
6	ChameleonV2 form variants (6 role-specific views)	#2, #3	2 weeks	Low
7	UAT with real equipment data	#3, #4, #5, #6	2 weeks	MEDIUM -- depends on client data availability

Milestones [D]

Milestone	Reached When	Target Date
M1: Core data model operational	Equipment CRUD + tag generation working E2E	TBD (CFIHOS access dependent)
M2: Workflow pipeline live	Full approval chain with RBAC gates functional	M1 + 2 weeks
M3: EDR integration tested	Bi-directional sync operational against EDR staging	M2 + 3 weeks
M4: UAT ready	All P1 stories deployed, real data loaded	M3 + 2 weeks

Section 10 -- What Is Needed [M]

#	Item [M]	From [M]	Blocking [M]	Status [M]
1	CFIHOS v2.0 Reference Data Library -- licensing and technical documentation	CFIHOS organization / client procurement	Yes -- blocks tag engine and property definitions	Open
2	EDR v6 production environment access for integration testing	PMG / EDR team	Yes -- blocks integration testing (critical path #5)	Open
3	Confirmed dev team resource allocation	Project sponsor	Yes -- blocks Sprint 1 start	Open
4	Client equipment data sample for UAT	Client operations team	No -- only blocks UAT phase	Open
5	Corporate identity provider configuration details (SAML/OAuth endpoints)	Client IT security	No -- local auth fallback available	Open

Section 11 -- Acceptance Criteria [M/D]

Definition of Done [D]

Criterion [D]	Verified By [D]
All P1 stories implemented and passing	UAT sign-off per story
CFIHOS tag generation produces valid tags for all standard equipment types	Tag validation test suite against CFIHOS reference data
Workflow approval chain functional with all 6 roles	E2E test with role-specific logins
EDR sync operational with < 5s real-time latency	Integration test against EDR staging environment
100+ concurrent users supported without degradation	Load test report
Full audit trail for all data modifications	Audit log review covering all CRUD operations

Success Metrics (30/60/90 days) [M]

Metric [M]	Target [M]	Measured By [D]
Equipment registration rate	100% registration within 6 months of go-live	Equipment count vs known asset inventory
Data accuracy	95% data accuracy maintained	Validation rule pass rate on stored records
Search time reduction	50% reduction in equipment info lookup time	User survey + system response time metrics
Tag automation rate	80% of tags auto-generated without manual override	Tag generation audit logs
Approval cycle time	90% reduction vs current manual process	Workflow time-to-completion metrics

Section 12 -- Risks [D]

#	Risk [D]	Likelihood [D]	Impact [D]	Mitigation [D]
R1	CFIHOS v2.0 implementation complexity exceeds team capabilities	High	High -- blocks core functionality	Engage CFIHOS consultant; prototype tag engine early; validate against reference data before full build
R2	EDR system availability and API stability for integration testing	Medium	High -- blocks integration milestone	Build against mock EDR API first; integration test in isolated staging; contract SLA for EDR uptime
R3	34/35 user stories lack detailed requirements for accurate estimation	High	Medium -- schedule risk	Sprint 0 dedicated to requirements elaboration before implementation begins
R4	User adoption resistance due to CFIHOS tagging complexity	Medium	Medium -- reduces value delivery	Auto-generation reduces manual complexity; visual compliance indicators; progressive disclosure in UI
R5	Key development team members unavailable during critical phases	Medium	Medium -- schedule delay	Cross-training; documented architecture; Nexus pipeline patterns reduce single-person dependency

Open Questions [M]

#	Question [M]	Impacts [D]	Resolution [M]
Q1	Has CFIHOS v2.0 licensing been procured?	Blocks Sprint 1 and tag engine development	Open -- needs client confirmation
Q2	What is the production EDR environment access timeline?	Blocks integration milestone (M3)	Open -- depends on PMG/EDR team
Q3	Are there data residency requirements constraining hosting location?	Infrastructure decisions (cloud vs on-prem)	Open -- needs client security team input
Q4	What is the expected equipment count for initial load?	Database sizing, migration planning, load test parameters	Open -- needs client operations data

Section 13 -- Cooperator Brief [D]

Field	Value
Scope [D]	Equipment registration system with CFIHOS/NORSOK tagging, 6-role RBAC workflow, maturity scoring, and bi-directional EDR v6 integration. 10 P1 user stories form the MVP.
Stack [D]	Node.js/Express backend, PostgreSQL + Redis, ChameleonV2 frontend (Nexus pipeline-driven), OpenAPI 3.0 REST, OAuth 2.0
Timeline [D]	M1 (data model): CFIHOS access + 3 weeks. M2 (workflow): M1 + 2 weeks. M3 (EDR integration): M2 + 3 weeks. M4 (UAT): M3 + 2 weeks. Total: ~10 weeks from blockers resolved.
Dependencies [D]	CFIHOS v2.0 license (blocker), EDR v6 staging access (blocker), dev team allocation (blocker), client equipment data sample (UAT only)
Interfaces [D]	Receives: CFIHOS reference data, corporate SSO tokens. Delivers: equipment data to EDR via REST API, reports/exports to users, audit logs for compliance.
Quality Bar [D]	CFIHOS compliance for all standard types. 95% data accuracy. Full audit trail. Load tested to 100+ concurrent. E2E tests covering all P1 stories.
Handover [D]	Deployed system + API documentation + user manual per role + admin guide + CFIHOS configuration guide + EDR integration runbook

Source Authority

Document Sources

This use case was compiled from the AER documentation archive at archive/AER/docs/html/. Key source files:

PROJECT_GOALS.html -- Business objectives and success metrics (Section 01, 11)
USER_STORY_REGISTER.html -- 35 user stories across 6 epics (Section 03)
WORKFLOW_MANAGEMENT_SPECIFICATION.html -- Approval chain and workflow states (Section 04)
DATA_MODEL_DOCUMENTATION.html -- Entity schema (Section 05)
AER_EDR_INTEGRATION_SPECIFICATION.html -- Integration architecture (Section 07)
AER_ARCHITECTURE_OVERVIEW.html -- Tech stack and infrastructure (Section 08)
RAID_LOG.html -- Risks and dependencies (Section 10, 12)
AER_DEPLOYMENT_CHECKLIST.html -- Deployment requirements (Section 08)

AER project status as of source documentation: 0% implemented. All 35 user stories documented; 1 has requirements defined, 34 not started. The project is requirements-only at this stage.