Don't Lose Sight of Your Process Safety Targets: The Critical Role of Pressure Relief Devices

• They are the final safeguard against overpressure scenarios.
• Their failure can lead to significant safety, environmental, and financial consequences.
• Regulatory codes mandate their periodic inspection and maintenance.
• Various factors can impact their performance over time, including:
  • corrosion, fouling, and mechanical wear;
  • extreme weather conditions; and
  • incorrect sizing.

• Resource Constraints: Limited staffing levels can delay scheduled inspections.
• Turnaround (TAR) Deferrals: When a planned outage is postponed, PRD inspection intervals might exceed recommended limits.
• Operational Risks: Performing inspections on active equipment presents safety concerns that must be carefully managed.

1. Prioritize Critical PRDs
   • Focus on high-risk relief devices where failures pose the greatest safety and operational risks.
2. Address PRDs that fail, leak, or lift in field
   • Reseat valves if it can be safely done.
   • Identify and mitigate causes of overpressure.
   • Assess alternate relief paths.
3. Routine Visual Inspection
   • Ensure proper valve installation and integrity of mechanical components including seals, bellows, and isolation valves.
   • Ensure valves are not leaking and functioning as intended.
4. On-Stream Testing (If Corporate Guidelines Permit)
   • Online testing allows verification of relief valve set pressure without removing the valve.
   • Best suited for non-corrosive, clean services to prevent contamination risks.
5. API 510 Simplified Deferral
   • Extends inspection intervals by up to 10% or six months, whichever is less.
   • Requires specific conditions to be met before approval.
6. Risk-Based Inspection (RBI) for PRDs
   • Evaluates probability and consequences of failure.
   • Helps extend inspection intervals for low-risk devices while ensuring more frequent checks on high-risk ones.

🔴 Challenges

• Requires extensive data collection and computational analysis.
• Involves significant initial investment to establish a plant-wide program.

🟢 Benefits

• Extends inspection intervals for ~70% of PRDs, reducing costs while maintaining safety.
• Ensures high-risk devices receive more frequent inspections, improving overall risk management.
• Aligns with RBI methodologies used for fixed equipment, providing valuable synergies.