Steps of the safety instrument SIS

The Hazop analysis should be carried out as per Step 1, the feasibility of improvements should be assessed, 2) the design institute shall carry out the design, and 3) it shall be implemented

1 Identify major hazard sources and hazardous processes in order to determine the scope of control covered by the SIS system； 2 Conduct a risk analysis to determine control measures ； 3 Consult relevant design institutes for the design ； 4 Establish a SIS system

1. Which installations require a SIS system: According to Document No. 116 issued by the State Administration of Work Safety, as of January 1, 2018, all newly built chemical processing installations and hazardous chemical storage facilities that fall under the category of “two key areas and one major hazard” must be designed with safety instrument systems that meet the required standards. Of course, older enterprises don’t have SIS systems, but those that fall under the category of “two key areas and one major issue” need to be upgraded ； 2. If necessary, an application can be submitted to initiate technical upgrades, using the company’s dedicated safety funds for this purpose ； 3. Hire a design institute for the design work ； 4. For HAZOP/LOPA/SIL classification, engage a safety consulting company to improve the design, thereby verifying that the SIS design meets the safety requirements of the facility ； 5. Procurement, modification construction, commissioning (commissioning records), commissioning for operation ； 6. Daily management: establish systems, set up records, and ensure proper operation.

First of all, it is merely a national regulation. It’s not just your family. So now there are design firms that specialize in providing end-to-end services. You just need to look for it locally. Their goal in establishing connections with the safety supervision authorities is to get approval through those authorities.

The last edit to this post was made by ZhiGE on 2019-1-5 at 11:09. After reading the replies above, I would like to add a few more points: 1. Chemical processing units and hazardous chemical storage facilities that fall under the category of “two key points and one major issue” must be designed with safety instrument systems that meet the required standards. It is the lessons of reality that teach us. So it is the safety requirements for equipment, personnel, and the environment, rather than just to pass the inspections by the safety supervision agency ； For example, in the reaction process of a high-pressure polyethylene plant, the temperature rises from the normal reaction temperature of 150°C to over 500°C due to abnormal decomposition of ethylene, and this occurs in no more than 500 ms; a SIS system is essential without it. 2. If a patent package is adopted, the design institute will carry out logical design based on the cause-and-effect table. Currently, there are generally two issues: A. Some interlock designs that are not related to process operations or personal safety can be incorporated into the SIS, when they could just as well be included in the DCS, which results in an overly complex system and difficulties in operation later on ； B. Some logic circuits with high SIL levels have an inappropriate number of instruments or inappropriate instrument selection, resulting in low availability ； 3. Engaging third parties to conduct HAZOP/LOPA/SIL analyses involves conducting in-depth analysis of the aforementioned issues; self-review generally makes it difficult to identify problems, and only through scientific methods can such analysis be carried out. 4. Of course, due to practical and commercial reasons (low quotes), as analyzed above, it is possible that this approach is merely a formality; nevertheless, the method and approach of analysis are excellent. In the end, it comes down to a balance between safety and investment; larger chemical companies have higher demands regarding safety and more funds at their disposal, so they generally follow the established procedures. Of course, extreme left and extreme right should be prevented, with everything always referred to as SIS. Rather, it should be a SIS with appropriate protection on the device.

Designed by the design institute, a HAZOP analysis and quantitative analysis must then be conducted according to the process flow, in order to determine the SIL level

Designed by the design institute, a HAZOP analysis and quantitative analysis must then be conducted according to the process flow, in order to determine the SIL level

This post was last edited by Yunmu on 2019-3-26 at 12:36. 1. Risk assessment is carried out through Hazard and Operability Study (HAZOP)； 2. Use protective layer analysis LOPA to allocate safety requirements, and determine the safety integrity level SIL ； 3. Find a designer to meet your company’s requirements.

Companies that want to install a SIS system should contact me; it meets the SIL2 certification standards, 18931103070