Safety relief valves management

Whereas numerous safety relief valves share many similarities, process safety interlocks are each individually tailored to the unique requirements of the process. The final parts of this chapter will discuss the critical process shutdown systems and the process safety alarms management systems used by three different major chemical plants. 

Piping and Instrumentation Diagram Probability of Failure on Demand Process Hazard Analysis Pressure Indicator Protection Layer Preventive Maintenance Process Safety Incident Database Process Safety Management Pressure Safety Valve (Relief Valve)... 

The need for metrics is particularly important in process safety, in no small measure because the hazards may not be readily evident. Unlike some other safety risks where dangerous situations are more apparent—such as unsafe scaffolding, unsecured cables, trenches, and other excavations—information on the status and safety of hazardous containment systems (e.g., internal corrosion, an improperly sized relief valve) is not generally visible. Without a constant and reliable flow of information on process safety performance and management systems, leaders may, in essence, be flying blind. 

There are also important discipline interfaces in the case of control valves, motorized control devices (such as electrically actuated valves), and safety and relief valves. The interface is easily managed if appropriate procedures are available from the start as to which discipline will be responsible for what. 

Organisation Organisation Inadequate quality control Inadequate quality control procedures. The information that the isolation valve on the safety relief vent remained in the closed position and locked-out was limited to a handwritten note. Although quality control measures (lockout/tag-out procedures to manage the work on the heat exchanger rupture disk were applied), the progress and current state of the maintenance job was not clearly documented. Moreover, there was not a post-maintenance quality check to verify if the service was properly concluded. 

Several possible safety-interventions were modeled with Platypus. These are examples of interventions that a safety-manager may consider. Three interventions are operational and three from the design of the unit. The replacement with better pressure relief valves, elimination of hoisting, and... 

Obviously, definition 2 would apply to a safety audit. The word audit implies a standard. The purpose of the audit is to find out if the standard is being met. This could be a standard for the number and location of fire extinguishers, whether operators have met certain training requirements, whether the relief valves on pressure vessels have been tested in the time period required, or virtually anything else that management deems essential to safety. Audits can involve any or aU of the following physical inspections, interviews, and review of documents and records. 

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