PSM, HAZOP, SIL, LOTO, QRA, BBS｜How much do you know about these key safety techniques?

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This post was last edited by yinkuilin6868 on 2015-12-14 11:04. PSM—Process Safety Management. Process Safety Management (PSM) differs from traditional safety management; its purpose is to prevent and mitigate accidental releases of process materials (or energy). Accidental leaks of process materials (or energy), although they occur after the process materials are introduced into the production facility, can be attributed to various stages such as process route selection, process design, product selection, procurement, installation, acceptance, commissioning, production, emergency response, maintenance, and changes. These issues affect almost all departments within the company, including senior management, engineering, procurement, production, maintenance, training, technical teams, and safety departments. It can be said that process safety management covers a wide range of aspects, involves many elements, and spans a long scope. Moreover, the hidden risks related to process safety are deep-seated; any issue in any stage can lead to process safety accidents. Currently, no safety management system can prevent process safety accidents; therefore, a systematic approach is needed to achieve this goal. Process Safety Management (PSM) includes the following 12 elements: Ø Process safety information Ø Process hazard analysis Ø Operating procedures Ø Work permits Ø Change management Ø Pre-startup safety inspections Ø Mechanical integrity Ø Incident/event management Ø Contractor management Ø Emergency response Ø Training Ø Compliance audits. These twelve management elements form an interrelated whole. Through the implementation of Process Safety Management (PSM), enterprises can adopt effective managerial and technical measures to address potential process hazards and risks associated with their process facilities, thereby improving their level of process safety management. HAZOP—Hazard and Operability Analysis: Node classification: Depending on the process, either the traditional European approach based on the main materials can be used, or the approach based on process units, which has become increasingly popular in China in recent years. Nodes are artificial divisions of the process flow imposed to facilitate HAZOP analysis; while this makes the analysis easier, it results in a lack of an overall perspective. Deviation selection: A combination of the empirical approach (i.e., giving priority to deviations close to the consequences) and the traditional approach (giving priority to deviations close to the causes) is used. For continuous processes, 18 common deviations that must be analyzed are selected, while for batch operations, 24 common deviations that must be analyzed are selected. By making meaningful combinations of all keywords and parameters, 124 deviations that may require analysis were identified as a supplement; this ensures both the quality of the analysis and improved efficiency, while also maintaining the overall competence of the analysts. Cause identification: Common causes of deviations are summarized, and 8 principles for cause identification are established to ensure the quality of the analysis. The 8 principles specify the need to identify the initial cause (sometimes also referred to as the direct cause), while also allowing the use of intermediate events as causes in certain special situations, and ensuring that these intermediate events are taken into account in the analysis. Consequence identification: To ensure the quality of analysis, 9 principles for identifying causes were established. These principles specify how to ensure that the ultimate adverse consequences are identified, while also allowing intermediate events to be used as consequences in certain special situations. At the same time, Principle 9 specifies when to analyze the consequential effects that occur after protective measures are activated, such as the activation of safety valves and interlock actions. Protection measures: To ensure the quality of analysis, protection measures are established based on three principles; the concept of an independent protection layer (IPL) is introduced, and guidelines are set regarding when administrative measures can be used as protection measures and when alarms can be used as such. Avoid the problem of protection measures focusing only on quantity rather than quality. Risk assessment: By using the protective layer analysis method, the frequency of accidents in various scenario is estimated, providing a basis for the team to determine whether the risk is acceptable. Recommended measures: To ensure the quality of the analyses, protection measures are established based on four principles; a distinction is made between effective recommendations and those that may be effective; it is specified when an independent protective layer must be used as a recommendation, and it is also determined when administrative measures can serve as recommendations, so as to ensure that the risks can be reduced to an acceptable level after the implementation of these recommended measures. SIL—Safety Integrity Level classification, verification, and validation. The classification of SIL is carried out by combining analyses such as HAZOP/LOPA, and it integrates seamlessly with SIF identification and SIL classification services. Taking into account the industry characteristics, the properties of the process equipment, the nature of the enterprise, and management requirements, appropriate risk management and SIL classification methods are employed. SIS’s engineering services include developing safety requirement specifications for users, as well as assisting with the selection of SIS equipment and structural design, providing professional technical guidance. The verification calculations for SIL include structural constraints, PFDavg calculation, and system capability analysis. Leveraging our extensive engineering experience, we carry out appropriate selection of data sources for calculating PFDavg and failure rate analysis, providing guidance for subsequent improvements to the SIF configuration in order to meet SIL requirements. SIL assessment of operational SIS systems——Many of the SIS systems in operation in our country have not been analyzed, designed, or maintained in accordance with **safety regulations and relevant functional safety standards. There are issues such as unreasonable functional design, inappropriate selection of components, and inadequate maintenance. Conducting a SIL assessment for it is an important step in optimizing the functional safety of SIS. Redefining SIF/SIL by leveraging our robust PHA technology and experience. By taking into account the actual operating conditions of the system, a re-evaluation of the SIL is conducted to provide professional support for the upgrading of SIS instrumentation and equipment, as well as for establishing and improving the management systems for SIS operation. SIS operation management services – provide end-users with professional services such as functional safety assessment, auditing, and establishment of management procedures for SIS. Combined with requirements such as asset integrity/mechanical integrity, it guides users in the professional maintenance and management of SIS by focusing on three aspects: personnel, management tools, and management and operating procedures. By leveraging modern technical means, a reliability database for SIS equipment and a computerized maintenance management system are established to monitor and manage the safety performance of SIS. Establish or improve daily inspection and maintenance procedures, as well as a document management system that includes records, spare parts management, SIS inspection and maintenance procedures, and SIS maintenance logs. By integrating safety standardization reviews, it provides professional guidance to help enterprises meet SIS management requirements. LOTO—Lockout/Tagout. Lockout/Tagout is a method commonly used in Europe and the United States during mechanical and electrical maintenance to prevent accidental operations by personnel. In the chemical and petroleum industries, it is usually used in conjunction with a permit system to avoid safety accidents. In China, there are few companies that can provide integrated labeling and locking services, including the development of procedures for labeling and locking, on-site training, as well as assistance in selecting locks and learning how to use them. Consulting firms need to have a thorough understanding of how locking mechanisms and energy isolation systems integrate with existing licensing systems. Engineers must possess practical experience in chemical, mechanical, and electrical operations and maintenance, and be able to assist clients in selecting appropriate locks and lockboxes based on the conditions at their sites, as well as provide on-site guidance on their use. QRA—Quantitative Risk Analysis. Quantitative risk analysis is the process of conducting a quantitative assessment of the impact that identified risks have on a company. The objects of quantitative risk analysis are those risks that, during the qualitative risk analysis process, are considered to pose a potential significant impact on the company. The process of conducting quantitative risk analysis involves analyzing the impacts of these risk events, serving as a quantitative method for making decisions in uncertain situations. By conducting quantitative risk analysis repeatedly, it is possible to understand the trend of risk development and identify the necessity of increasing or decreasing risk management measures. Comprehensive analysis software includes the 2D leakage consequences analysis tool Phast, the 3D CFD calculation and analysis tools FLACS and AutoReaGas, the leakage frequency calculation tool Leak, and the personal and societal risk assessment tool Safeti ； In terms of databases, these include the equipment failure frequency database, the Historical Failure Database for Hydrocarbon Leaks (HCRD), and the Equipment Reliability Database (OREDA). Based on practical experience and the local conditions, the data has been adjusted to create a equipment failure frequency database with more localized characteristics. QRA engineers should possess practical experience in applying methods to calculate individual risk contours and social risk curves, providing data support for enterprises to determine the safety distances between hazard sources and protective measures outside the facility, thereby ensuring the safety, compliance, scientific validity, and rationality of site selection ； Verify and optimize the layout of equipment and facilities within the plant, to ensure that the plant’s planning as well as the arrangement of equipment are safe, compliant, scientific, and reasonable ； Two-dimensional and three-dimensional computational analyses are conducted on typical leakage and fire incidents involving equipment and facilities, to determine quantified risk data and provide numerical values for risk analysis. This helps identify the scope and affected areas of such incidents, offering data support for the development of emergency response plans and accident investigations. BBS—Quantitative Risk Analysis. Behavior-Based Safety, which is the foundation of BBS, is a safety management tool that involves observing work behaviors and facilitating communication in order to gradually eliminate unsafe behaviors and reinforce safe ones, thereby fostering a strong safety culture over time. DuPont’s STOP, CNOOC’s Five Thinks and Five Don’ts for behavior safety observation, Sinopec’s safety observation and communication, and Yantai Wanhua Group’s safety audits are all other names for BBS. However, in the actual implementation process, BBS encounters many specific difficulties, including: Ø The prerequisites for implementing BBS; Ø How to observe human behavior on computer-controlled production lines; Ø Whether management behaviors need to be observed; Ø What types of unsafe conditions require monitoring; Ø Whether BBS data should be combined with data on identified risks and corrective actions; Ø Who needs to be monitored; and whether contractors need to be under observation. For these common issues, BBS Consulting Company needs to provide clear explanations. For large clients, BBS data needs to be statistically analyzed, and manual statistical analysis is very cumbersome.