Objective

The aim of the Decommissioning phase is to guide the safe and effective retirement or replacement of level crossing technologies once they reach the end of their operational life or no longer meet safety, usability, or regulatory requirements. This phase ensures safety continuity, cost-efficiency, and compliance while preparing for a smooth transition to newer technologies.

System retirement/replacement

Description

Over time, even well-performing technologies reach a point where they are no longer viable. Retirement or replacement may be triggered by:

• Escalating operational and/or maintenance costs
• Functional or safety limitations under evolving conditions
• Regulatory or user expectations outpacing system capabilities
• Technological obsolescence (eg end of supplier support, integration issues)
• Inability to accommodate upgrades due to design constraints

Because level crossing systems are safety-critical and operate in environments requiring uninterrupted functionality, retirement and replacement should be approached strategically, with robust planning, stakeholder input, fall-back mechanisms in place, and, where needed, parallel deployment of new systems with legacy systems.

Key activities

1. Plan retirement and replacement. Initial project scoping should include a notional end-of-life plan. Review this as the technology matures and field experience accumulates. For example, a prototype in-vehicle alert system deployed for trials may be planned for replacement after 3 years pending evaluation outcomes.
2. Perform gap analysis – legacy vs. future needs. Compare current capabilities (eg detection range, false alarm rate, user acceptance) with updated safety and user requirements. Determine if upgrades are feasible or if new technologies (eg AI/computer vision, V2X) are needed.
3. Evaluate cost of upgrade vs. replacement. Analyse total lifecycle costs, including licensing, hardware, retraining, and the cost of ongoing support. For instance, if maintaining sensors requires frequent calibration or supplier support has ended, replacement might be cheaper long-term.
4. Develop replacement/retirement strategy. Safety-critical systems (eg obstacle detection) require parallel deployment of the new system before decommissioning the old one. Verification and validation must occur with minimal downtime. Non-critical systems (eg user alert apps) may allow for smoother transition, provided fallback warnings are in place. Infrastructure (eg mounting poles, solar power units) and support systems (data storage, comms networks) may also need upgrading or replacement.

Human Factors contributions to system retirement/replacement

Human Factors plays an important role in ensuring that system retirement or replacement does not create safety gaps, degrade usability, or introduce workload, comprehension, or procedural errors during the transition.

1. Plan retirement and replacement. Contribute to early end-of-life planning by identifying user tasks, system dependencies, and critical operations affected during the transition period. Human Factors specialists can also contribute by ensuring user needs, staffing, and transition communications are addressed in strategy development.
2. Support gap analysis - legacy vs. future need. Human Factors Impact Analysis can be utilised to determine how the transition will affect user tasks, workload, situation awareness, errors and other Human Factors-related issues. Consideration should also be given to fallback solutions or process workarounds to maintain task performance in the interim (eg manual procedures or redundant alerts). Use the Human Factors Risk Assessment Prompts to support consideration of transition risks.
3. Support evaluation of cost of upgrade vs. replacement. Human Factors input can contribute to Options Analysis, including the costs of training, user re-familiarisation, impacts on error rates, and transition risks. Further, input can consider the user-related consequences of technology obsolescence (eg declining usability).
4. Develop replacement / retirement strategy. Human Factors can contribute to the design of safe transitions (eg the design of parallel operation periods, fallback procedures, interface phase-outs), guide training needs, stakeholder communication, and operator handover processes and evaluate human-system interface changes and residual risk during migration.