Process equipment operating safety

The AIChE (American Institute of Chemical Engineers) CCPS (Center for Chemical Process Safety) Process Equipment Reliability Database (PERD) initiative has rigorously identified and documented failure modes for instrument loops, which encompass control, indication, alarm, and automatic protection (Ref. 3). An excerpt from those lists shows a comparison of failure modes applicable to BPCS versus SIS (Figure 2-2). The ability of operations personnel to detect these failure modes is also quite different. 

Safe handling practices are essential at all stages of production, from the laboratory to the manufacturing operations. The safety committee should inspect and advise on processing equipment and be responsible for providing personal protection, eye wash fountains, safety showers, etc. 

Introduction Review and audit processes are used in the chemical process industry to evaluate, examine, and verify the design of process equipment, operating procedures, and management systems. These processes assure compliance with company standards and guidelines as well as government regulations. Reviews and audits can encompass the areas of process and personnel safety, environmental and industrial hygiene protection, quality assurance, maintenance procedures, and so on. 

The assessor should also find out whether an effective testing program is in place to help ensure the serviceability of process measurement equipment. The successful toller should have an established calibration program to address the accuracy of critical measurement equipment. Safety critical process parameters should be monitored and critical process equipment should automatically interlock when monitoring instrumentation detects safety critical deviations. Interlocks should either facilitate a remedy to the critical deviation or bring the process to the zero energy state. These instruments and interlocking devices should be routinely tested to ensure operational reliability. 

Other information may also benefit the PHA. Standard operating procedures for processing equipment, safe work practices, maintenance or job safety analyses, emergency response plans could be appropriate review items for some PHAs depending upon the toll. 

The environmental conditions contemplated for tlie operating equipment also must be evaluated. Many of the unit operations are used in conjunction witli or in close proximity to process equipment and, tlierefore, the safety of tlie overall operation is involved. 

All process equipment has procedures to operate and meet safety requirements. They include a checklist that includes preparation (moving material, etc.), startup and shutdown procedures, tooling changes, and to cleanup of all equipment. Most equipment generates high heats and pressures. They are built to run safely, but they must be treated with respect . 

Processing equipment has standard procedures to operate and meet safety requirements. Safety information and standards are available from various sources that include the equipment suppliers, Society of Plastics Industry (SPI), and American National Standards Institute (ANSI). For the past century we have observed increasing activity on the... 

Building 5—A motor control center (MCC) constructed of unreinforced masonry. An electrician spends 1 hour a day monitoring equipment in the MCC. The MCC provides power for process equipment critical to the continued operation of the facility. Critical power for safety shutdown equipment for both Process Units 1 and 2 is located in Building 5. 

Under the management of change section of the PSM standard employees are required to develop and implement documented procedures to manage changes in the process chemistry, process equipment, and operating procedures. Before a change occurs (except for replacement-in-kind), it must be reviewed to ascertain that it will not affect the safety of the operation. After the change has been made, all the affected employees are trained, and a pre-startup review is conducted. 

D espite many safety precautions within chemical plants, equipment failures or operator errors can cause increases in process pressures beyond safe levels. If pressures rise too high, they may exceed the maximum strength of pipelines and vessels. This can result in rupturing of process equipment, causing major releases of toxic or flammable chemicals. 

The reviewers simply meet in an informal fashion to examine the process equipment and operating procedures and to offer suggestions on how the safety of the process might be improved. Significant improvements should be summarized in a memo for others to reference in the future. The improvements must be implemented before the process is operated. 

During the plant design the safety of process equipment is also recognized by layout. The objectives of layout are to minimize risk to personnel, to minimize escalation (both within the plant and to adjacent plants), and to ensure adequate emergency access. It is also essential to ensure adequate access for maintenance and operations. Plant layout is a crucial factor in the safety of a process plant because of e.g. segregation of different risks, containment of accidents and limitation of exposure. Safe plant layout is designed on the basis of design... 

The comparison of the safety of equipment is not straightforward. It depends on equipment themselves and process conditions. Equipment safety can be evaluated from quantitative accident and failure data and from engineering practice and recommendations. Experience-based information is found from layout recommendations and safety analysis methods such as the Dow E F Index (1987). Quantitative data can be found from accident and operational statistics. It should be remembered that all reliability or failure information does not express safety directly, since all failures are not dangerous and not all accidents are due to failures of equipment. 

Process Reliability Simulation VIP The process reliability simulation VIP is the use of reliability, availability, and maintainability (RAM) computer simulation modeling of the process and the mechanical reliability of the facility. A principal goal is to optimize the engineering design in terms of life cycle cost, thereby maximizing the project s potential profitability. The objective is to determine the optimum relationships between maximum production rates and design and operational factors. Process reliability simulation is also applied for safety purposes, since it considers the consequences of specific equipment failures and failure modes. 

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