Equipment operated with process conditions (e.g., temperature, pressure, level, flowrate) outside of safe operating limits (high or low) can result in unstable and unpredictable operation and the potential for process safety incidents. It is therefore important to understand the operating limits of the plant and stay within that operating envelope. It is useful for teams to discuss how these limits are documented at their site and whether the limits are clear and available.
🔺 We discuss and use the approved operating limits for our location.
🔺 We escalate where we cannot work within operating limits.
🔺 We alert supervision if an alarm response action is unclear or the time to respond is inadequate.
🔺 We obtain formal approval before changing operating limits.
🔺 We confirm that potential for overpressure from temporary pressure sources has been addressed.
PSF We Stay Within Operating Limits Video
This Safety Moment is based on an incident in which two people were seriously injured when a 3.4l nitrogen cylinder was being filled to 200bar.
Blown control valve cover
As part of project commissioning activity, some actuated valves on a gas metering system, including a pressure control valve, were to be held open.
High Value Learning
Hydraulic over torqueing of bolted joint equipment
Two incidents have occurred during the hydraulic torqueing of bolted joints on assets operated by two different operators in the UKCS.