Resilience of Maintenance Operations for Critical Healthcare Assets: Ultra Clean Ventilation Systems in NHS Operating Theatres

Ultra Clean Ventilation (UCV) systems maintain sterile surgical environments in NHS operating theatres through contaminant dilution, particle filtration, and directional airflow control, and are the primary engineering control against the surgical site infections that affect approximately 11% of surgical patients at per-case treatment costs typically exceeding £5,000. Resilient maintenance operations are therefore essential to withstand failures, mobilise resources, and restore functionality within clinically acceptable timeframes. This study employs a single case study design, using archival documentary analysis of 42 classified failure events (2017–2025) from one NHS operating theatre. The 4R resilience framework is applied across four dimensions: Robustness (R₁), Redundancy (R₂), Resourcefulness (R₃), and Rapidity (R₄). Analysis yields: R₁ = 45.5%, R₂ = 46.7%, R₃ = 58.4%, and R₄ = 34.3% (documented-events estimate; 4.9–90.6% under bounding assumptions). Findings reveal strong information management capability alongside critical gaps in redundancy, financial resourcing, and recovery speed. This represents the first application of the 4R resilience framework to a UCV system in an NHS operating theatre, providing a methodology and an evidence-based baseline for replication across NHS estates.