Eleven best practices and principles
Learning from events includes effective process safety management to prevent these events from occurring. The following 11 key principles about parking should always be followed:
1. After each emergency stop, formulate the operating rules for driving, such as:
Conduct and complete a thorough pre-drive safety check
After stopping, open the lines and equipment in accordance with proper safety procedures
Perform change management (MoC) analysis of equipment, processes and operating procedures.
2. Develop detailed written operating procedures to avoid the possibility of valve dislocation during opening and stopping. If required, a written checklist and diagram shall be provided to verify the correct position of the valve.
3. This kind of accident often has operational deviation during the operation and parking, because the operator does not know the impact of the change. Therefore, review the change management (MOC) policy to ensure that it adequately addresses changes due to operational differences. In order to maximize the effectiveness of the change, the following activities should be included:
Identify safe scope, variables and activities for process operating conditions and train personnel to identify significant changes. Combined with an understanding of established operating procedures, this additional training will enable operators to initiate the MoC system when appropriate.
Use multidisciplinary and specialized knowledge in analyzing deviations
Communicate in writing the basic elements of the new operating procedure
Communicate in writing the scope of potential hazards and safe operations
Provide training to operators according to the complexity of the new operating procedures
Periodic reviews to determine the effectiveness of the plan
The Lockout tagout (LOTO) procedure shall specify that the device is in full condition before starting or maintaining it. The equipment start-up procedure shall include a stop operation rule which shall specify the conditions for the safety equipment to be started safely (such as whether the equipment is unpressurized), and a higher level of management review and approval is required if this cannot be confirmed.
5. Make sure to use proper program isolation equipment after parking. Do not rely on the closing of the single-seat globe valve, or a leak may occur. Instead, double-blocking components and valves should be used to insert blind plates or physically disconnect device components to ensure they are in an appropriate isolation state. For devices in "standby mode," continue to monitor key parameters, such as pressure and temperature.
6. The computer control system shall include an overview of the process and a material balance analysis to ensure overall operator supervision of the process.
7. Technical support shall be provided to operators through various communication channels for complex and critical process systems. Especially during abnormal operating conditions (such as device start-up), if the operator has a different or contradictory understanding of the process device state, the safety risk will be greater. Effective communication is therefore essential and requires action tracking.
8. During the start-up and shutdown of the device, ensure that the operators are under the supervision and support of experienced technicians and are fully trained for the control system they will operate, and consider the use of simulators for training and guidance.
9. For high-risk processes, establish shift schedules to minimize the impact of operator fatigue. Shift work systems should manage normal shift patterns by limiting working hours per day and consecutive working days.
10. Calibrate and function test the newly installed computer controls before starting the device.
11. The importance of critical safety equipment should not be ignored when troubleshooting the device during start-up and shutdown.