🧭 RTT Facilities — Corridor Classification Standard
Spatial Risk Units & Governance Boundaries
This document defines the Facilities‑level corridor classification standard used to group, assess, and govern spatially linked infrastructure assets.
It is grounded in the RTT Facilities Playbook and applies across all Facilities domains, including RTT‑AGERI.
Domain‑specific initiatives extend this standard with asset‑specific criteria.
1. Purpose#
Facilities risk is rarely isolated to single assets.
The purpose of corridor classification is to:
- Group assets that share exposure, load, and failure dynamics
- Enable spatial risk assessment and prioritization
- Support propagation modeling and intervention planning
- Align modernization with capital timing
- Provide a stable governance unit across domains
Corridors are treated as first‑class governance objects.
2. Corridor Definition#
A corridor is a spatially and functionally linked grouping of assets that:
- Share environmental exposure
- Experience correlated load or stress
- Exhibit coupled failure or degradation patterns
- Can propagate risk internally or externally
Corridors may cross administrative or jurisdictional boundaries.
3. Classification Dimensions#
Corridors are classified using multiple dimensions:
- Structural condition (drift, harmonics)
- Environmental exposure (climate, terrain)
- Load and usage intensity
- Redundancy and resilience
- Propagation potential
- Societal impact
No single dimension determines classification.
4. Corridor Classes#
Facilities corridors are classified into five canonical classes:
| Class | Designation | Description |
|---|---|---|
| C‑0 | Stable | Low risk, within tolerance |
| C‑1 | Watch | Early degradation signals |
| C‑2 | Concern | Persistent risk requiring planning |
| C‑3 | Critical | High risk, modernization prioritized |
| C‑4 | Fragile | Failure likely or imminent |
Classes reflect trend and interaction, not snapshots.
5. Scoring Integration#
Corridor classification integrates:
- Drift scoring
- Harmonics scoring
- Propagation modeling
- Failure mode patterns
- Environmental stress indicators
Classification is reviewed periodically and after major events.
6. Governance Thresholds#
Corridor class determines governance response:
| Class | Governance Action |
|---|---|
| C‑0 | Routine monitoring |
| C‑1 | Preventive review |
| C‑2 | Modernization planning |
| C‑3 | Capital prioritization |
| C‑4 | Escalation and intervention |
Reclassification requires documented justification.
7. Capital & Modernization Alignment#
Corridor class informs:
- Modernization cycle selection (10 / 20 / 50‑year)
- Capital allocation priority
- Intervention class escalation
- Audit focus
Corridor inflation is treated as a governance risk.
8. Cross‑System Considerations#
Corridors may:
- Contain multiple asset classes
- Intersect with other corridors
- Act as propagation bridges between systems
Cross‑system corridors trigger Facilities‑level review.
9. Relationship to Domain Extensions#
Domain initiatives (e.g., RTT‑AGERI):
- Extend this standard with asset‑specific criteria
- Define measurement techniques
- Map domain corridors to these canonical classes
They do not redefine corridor classes or governance thresholds.
10. Canonical Status#
This standard is canonical.
All Facilities domains must reference it when defining, scoring, and governing corridors.