📋 Case Study

Pharmaceutical Cleanroom HVAC Failure Risk Mitigation

Single-point HVAC failure risking sterile environment integrity and product loss

🏗️ Project Overview

GMP-compliant biologics facility, Singapore

🎯 Challenge

Single-point HVAC failure risking sterile environment integrity and product loss

🔧 Design Approach

Fault Tree Analysis (FTA) + redundancy design with dual air-handling units and pressure cascade mapping

📐 Design Diagram

MTTR=7hAHU-2MTBF=8760h
MTTR=7h✓A = 99.92%Cleanroom ZoneP_contam = 0.0042/yrSingle-Point Failure RiskSterility breach • Product lossPressure Cascade→

AI-generated project design illustration

📐 Key Calculations

System Availability

A = MTBF / (MTBF + MTTR)

Result: 99.92%

Meets FDA Annex 1 requirement for critical systems

Probability of Contamination Event

P = λ × t

Result: 0.0042/year

Below ALARP threshold of 1×10⁻³/year

📊 Results

Zero regulatory citations; contamination events reduced from 3.2 to 0.1/year; passed MHRA audit with zero observations

💡 Lessons Learned

• •FTA must include human procedural failures, not just hardware
• •Pressure differential mapping is essential for verification

✅ Key Takeaways

• 1FTA must include human procedural failures, not just hardware
• 2Pressure differential mapping is essential for verification