3.2 Standard type: usually used as indicator light, with half value angle of 20 °~45 °; Led Chip Processing,High-Power Lamp Beads,Purple Lamp Bead Sterilization,Smd Led Lights Sterilization Dongguan XINYUDA Technology Co., Ltd. , https://www.gdxige.com 1. Process Risk Management Standard (PAMS)
Dow Chemical applies process risk management theory to enterprise safety management, develops its own corporate standards, and vigorously promotes Dow's chemical process risk management standards in its affiliated companies. In-house production line managers use risk management techniques to achieve continuous risk reduction goals; use systemic risk management to assess and control hazardous materials, processes, and activities (possibly causing harm to personnel or damage to property and the environment) ).
1) Purpose of implementing process risk management standards
The purpose is to conduct process risk management for sudden hazards caused by fire, explosion or chemical spills, determine risk assessment requirements for the entire life cycle of the facility, and prioritize, analyze, and prioritize risks.
2) Scope of application of process risk management standards
This standard applies to investment projects, existing facilities and their changes, sudden process hazards arising from Dow Holdings and joint ventures, market development or semi-commercial facilities.
2. Main contents of process risk management standards
There are five main tools for process risk management standards: reactive chemicals - process hazard analysis (RC-PHA), fire explosion index (F&EI), chemical exposure index (CEI), structured scene analysis (HAZOP), Protective Layer Analysis (LOPA).
1) Reactive Chemicals - Process Hazard Analysis (RC-PHA) Review
Reactive Chemicals - Process Hazard Analysis (RC-PHA) is a one- to two-day review conducted by a multidisciplinary team that includes: process chemistry, integrity of risk management plans, worst case assumptions and The establishment of major defense lines, historical accidents, process changes, training and education programs, questionnaires, and implementation of recommendations from previous reviews. Dow Chemical requires that all factories with a capital of more than $50,000 be reviewed every three to five years and that all new production leaders be required to perform the RC-PHA review 90 days after they take office. In addition, Dow Chemical is actively promoting the establishment of global chemical reactivity standards.
2) Dow Chemical Fire and Explosion Index (F&EI)
The Dao Chemical Fire and Explosion Index method is a method for analyzing the fire and explosion hazard of chemical processes and production equipment. It is based on accidents in enterprises other than Dow Chemical in history, mainly in the design stage and cycle. Used during the first level of sexual review, focusing on areas of greatest risk. The method uses a calculation table to classify other related processes according to the calculation results. Its main advantages are: helping to take into account equipment layout issues during the design process, encouraging intrinsic safety design, and leading to more detailed review.
3) Dow Chemical Exposure Index (CEI)
CEI is a simple method for predicting vapor diffusion, mainly to deal with potential and serious personal injury in industrial accidents. It is based on the Emergency Response Planning Standard (ERPG) concentration and is suitable for pipeline ruptures, overflows from container tank ruptures, and other standard accident scenarios resulting from HAZOP and empirical analysis. According to industrial health and safety standards, there are three different concentration levels depending on the concentration of the chemical. Level 1 (minimum), Level 2 (medium), Level 3 (maximum).
4) Structured scenario analysis
Structured scenario analysis is a systematic approach to analyzing the hazard of a device by reviewing the process on a line-by-line basis. Various methods, such as HAZOP, fault hypothesis analysis, checklists, etc., can be used for structured scene analysis, of which HAZOP is most commonly used. CEI and F&EI are used for high-risk target areas in accordance with the requirements of risk management standards for high-risk (process) processes. This method works well for causal pair identification. Partial design guidelines for most process changes. Dow Chemical uses third-party software (PHA-Pro from Dyadem) for structured scenario analysis.
5) Protective layer analysis (LOPA)
Protective Layer Analysis (LOPA) is a semi-quantitative analytical method that bridges the gap between qualitative and fully quantitative methods. Coverage analysis is a risk analysis technique developed from event tree analysis. From the initial event, whether the security protection measures play a role (success or failure) in the process of accident development, and whether the process is required to be safe. Level and propose corresponding safety measures to reduce the risk to an acceptable level. Compared with other analytical methods, the protective layer analysis has the following advantages: less time required for quantitative risk assessment (QRA); a protective layer that is effective for each triggering event can be identified; and resources for reducing risk can be effectively allocated. Inadequacies can be made up by a safety instrumented system. Because of the above advantages of LOPA, Dow Chemical has promoted and used protective layer analysis in its subsidiaries in recent years, while structural hazard analysis (HAZOP, failure hypothesis analysis, checklist) analysis is used less, Dow Chemical technicians The combination of protection layer analysis and fault tree is also used to make the analysis results more correct.
3. Dow Chemical Process Risk Management (PRM) Overview
Due to different risk analysis methods, different manpower and material resources, different theoretical levels and management requirements, it is impossible and unnecessary to adopt complex risk analysis methods for all facilities and all materials. In order to make more efficient use of skill resources, Dow Chemical Process Risk Management mainly uses a layered risk analysis method, and the whole process is divided into four layers.
1) The first layer is a process hazard analysis of all facilities, using Fire Explosion Index (F&EI), Chemical Exposure Index (CEI), LOPA Target Value, Reactive Chemicals - Process Hazard Analysis (RC/PHA) Questionnaires and other methods.
2) The second layer is an additional risk check for the specific unit operation of the facility, using causal pair identification, LOPA (Dow Chemical analysis of new processes, HAZOP analysis), explosion shock (building overpressure) evaluation, structural hazard Analyze (HAZOP) and other methods.
3) The third layer is an enhanced risk check for the target process, mainly for the quantitative risk assessment (QRA).
4) The fourth layer is to select a few devices for qualitative and quantitative risk assessment. The selection is based on the combination of the results analysis and the frequency of the accident, and the quantitative risk assessment focuses on high-risk activities.
The sequence of analysis processes ranges from simple methods to complex analysis, from lower levels of management to higher levels of management, from all substances to selected few substances. Using a layered approach, more sophisticated risk analysis tools are applied in high-risk analysis.
3.3 Scattering type: This is an indicator light with a large angle of view. The half-value angle is 45 °~90 ° or more, and the amount of scattering agent is large.
4. Classification according to the structure of LED
4.1 According to the structure of LED, it is divided into full epoxy encapsulation,
4.2 Metal base epoxy encapsulation
4.3 Ceramic base epoxy packaging and glass packaging.
5. Classification by luminous intensity and working current:
5.1 LED with ordinary brightness (luminous intensity 100mcd) is divided according to luminous intensity and working current;
5.2 The luminous intensity between 10 and 100 mcd is called high brightness LED.
5.3 The working current of general LED is between 10 mA and 10 mA, while the working current of low current LED is below 2 mA (the brightness is the same as that of ordinary LED).