Understanding High Integrity Pressure Protection Systems (HIPPS): A Modern Safety Imperative in Process Industries

In high-pressure process environments such as oil and gas, petrochemical, and power generation, ensuring operational safety and asset protection is non-negotiable. Among the critical safety layers employed in such industries, the High Integrity Pressure Protection System (HIPPS) has emerged as a vital technology, designed to prevent over-pressurization and catastrophic failure.

What is HIPPS?

A High Integrity Pressure Protection System (HIPPS) is a safety instrumented system (SIS) designed to automatically detect and isolate over-pressure conditions in pipelines or vessels. Unlike traditional relief systems that vent excess pressure to the environment, HIPPS is a closed system that prevents the release of hazardous substances, offering both safety and environmental protection.

Key Components of HIPPS

Pressure Sensors/Transmitters: These detect high-pressure levels and send real-time data to the logic solver.
Logic Solver: The core processing unit that interprets sensor inputs and decides whether to initiate a shutdown.
Final Elements (Shut-off Valves): Fast-acting valves that isolate the high-pressure section when triggered.

Why Use HIPPS?

Traditional overpressure protection methods often involve pressure relief valves or rupture discs that allow the release of gas or liquid to relieve pressure. However, these methods come with several challenges:

Environmental Impact: Releasing toxic or flammable substances can pose serious environmental and safety hazards.
Regulatory Compliance: Stricter regulations worldwide demand better containment and mitigation strategies.
Cost Efficiency: Avoiding venting or flaring translates to reduced loss of valuable product and minimizes the need for downstream treatment.

HIPPS addresses these challenges by shutting in the process before an overpressure situation can occur, offering a non-relief-based protection strategy.

Applications Across Industries

HIPPS is widely used in:

Oil & Gas (Onshore and Offshore): To safeguard pipelines, separators, and compressors.
Chemical and Petrochemical Plants: For reactor and storage tank protection.
Refineries: To prevent overpressure in distillation and conversion units.
Power Generation: Especially in high-pressure steam circuits and turbine systems.

Benefits of HIPPS

✅ Enhanced Safety: Prevents potentially catastrophic events.
✅ Environmental Stewardship: Limits emissions and product loss.
✅ Compliance with International Standards: Meets IEC 61508 and IEC 61511 for functional safety.
✅ Optimized Design: Allows for cost-effective equipment by reducing the need for over-sized piping and vessels.

Standards and Compliance

HIPPS systems are generally designed in accordance with IEC 61508 and IEC 61511, which define safety integrity levels (SIL). Depending on the risk assessment, HIPPS may need to comply with SIL 2, SIL 3, or higher, ensuring it performs reliably under all circumstances.