【2026 Emergency Shutoff】Must the emergency shut-off valve be a SIS valve?
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This post was last edited by The one on 2026-7-8 10:37. An emergency shut-off valve is a valve installed on tank trucks, tank containers, storage tanks, or pipelines, which can be quickly closed manually or automatically in emergency situations. Different standards emphasize different aspects of its definition: the \"Emergency Shut-off Valves for Liquefied Gas Equipment\" (GB/T 22653-2008) stresses its function of rapid shutdown in emergency situations ； \"Emergency shut-off valves for cryogenic media\" (GB/T 24918-2010) specifies the triggering condition as \"in the event of an accident\"” ； The \"Safety Management Specifications for Liquefied Hydrocarbon Storage Areas in Chemical Enterprises\" (AQ3059-2023) specify its function as \"preventing overfilling of the storage tanks, and enabling rapid manual or automatic shutdown and isolation of the material in the event of accidents such as fires or leaks within the storage area\"” ； The \"Safety Design Code for Spherical Storage Tanks of Liquefied Hydrocarbons\" (SH/T 3136-2025) refers to it as an \"emergency shut-off valve\", requiring it to have both automatic and manual shutdown functions; the manual shutdown function shall include remote manual shutdown from the control room as well as on-site manual shutdown. With the issuance of the \"Safety Technical Regulations for Safety Accessories of Pressure-bearing Special Equipment\" (TSG 92-2026), emergency shut-off valves have been included for the first time within the scope of regulation regarding safety accessories for special equipment. In practical engineering applications, a key question arises: Is the emergency shut-off valve the same as an SIS (Safety Instrumented System) valve?
🔺1) Article 3.17 of the \"Safety Management Specifications for Liquefied Hydrocarbon Storage Areas in Chemical Enterprises\" AQ3059-2023: Switch valves installed on the liquid-phase inlet and outlet process pipelines at the bottom of the storage tanks, designed specifically to prevent overfilling of the tanks, and to enable rapid manual or automatic shutdown and isolation of the flow of material in the event of fires, leaks, or other accidents in the storage area. (Note: This document is applicable to the safety management of newly built, expanded, or renovated liquefied hydrocarbon storage areas within the premises of chemical enterprises (including petrochemical, coal chemical, fine chemical industries, etc.), as well as existing liquefied hydrocarbon storage areas.)
🔺2) \"Specifications for the Installation and Use of Emergency Shutoff Valves in Hazardous Chemical Enterprises\" T/CCSAS023-2022. Emergency shutoff valves are classified into three categories: I, II, and III. Class I: Valves that are installed in piping systems and operated manually on-site. The valve should be installed at a horizontal distance of not less than 15 m from potential leakage sources, at a height of no more than 4.6 m above the ground, in a location on the ground or platform that is easy to operate. The size of such emergency shut-off valves is not larger than DN200, and the pressure rating is not higher than PN50.
Class II: Valves installed in piping systems that are operated locally using power. The valve should be installed at a horizontal distance of not less than b) 15 m from potential leakage sources, at a height of no more than 4.6 m above the ground, in a location on the ground or platform that is easy to access. This type of emergency shut-off valve is operated by electric, hydraulic, or pneumatic actuators, and it has a start button on the valve.
Class III: Valves that can be controlled locally and remotely via power. There are no restrictions on the horizontal distance between the valve and potential leakage sources, nor on the height of the valve above the ground. The local operation button for the valve must be at a horizontal distance of at least 15 meters from potential leakage sources, and it can be operated from the ground or from a control room.
Note: This document applies to the installation and use of emergency shut-off valves in hazardous chemical enterprises. This document does not apply to automobile fuel, gas, and hydrogen refueling stations, long-distance oil and gas pipelines, LNG production facilities and storage installations, urban gas systems, as well as hazardous chemical production facilities and storage installations used for national defense research and production.
🔺3) «Emergency shut-off valves for liquefied gas equipment» GB/T22653-2008, Article 3.1: Valves installed on tank trucks, tank containers, storage tanks, or pipelines, which can be quickly closed manually or automatically in emergency situations.
🔺4) \"Emergency shut-off valves for low-temperature media\" GB/T 24918-2010, Clause 3.1: Valves installed on tank trucks, storage tanks, or pipelines, which can be quickly closed manually or automatically in the event of an accident.
🔺5) Article 3.3 of the \"Safety Design Code for Spherical Storage Tanks of Liquefied Hydrocarbons\" SH/T 3136-2025: Accident isolation valves: These are switch valves installed on the inlet and outlet pipelines of spherical storage tanks for liquefied hydrocarbons, and they enable rapid and secure shutdown (TSO) and isolation in the event of fires, leaks, or other accidents involving the tanks. The accident isolation valve shall have automatic and manual shutdown functions, with the manual shutdown function including remote manual shutdown from the control room and on-site manual shutdown. The core function of an emergency shut-off valve is to enable rapid response in emergency situations, allowing the valve to be closed or opened promptly thereby effectively preventing accidents.
🔺6) Article 2.0.1 of the \"Design Standards for Emergency Isolation Control Valves in Petrochemical Plants\" T/HGJ 12402-2021: Emergency isolation control valve: A remotely controlled valve installed within petrochemical plants, between liquefied hydrocarbon equipment and its extraction pumps, located near the base of the liquefied hydrocarbon equipment. When a fire breaks out in the extraction pump, close this remote control valve to cut off the flow of liquefied hydrocarbon material to the extraction pump, thereby quickly extinguishing the fire.
🔺7) According to the Safety Technical Regulations for Safety Accessories of Pressure-Type Special Equipment, TSG 92-2026 A3.1, such valves are those that, in abnormal or emergency conditions, rely on sensors that detect changes in the concentration of the medium, or on changes in the pressure, flow rate, ambient temperature, or external forces acting on the connection points, to trigger the valve’s built-in shut-off mechanism or components, thereby causing the valve to close automatically; however, they require manual mechanical operation to be opened. A3.2 Classification of emergency shut-off valves: (1) Flow-over shutdown type emergency shut-off valve ； (2) Fusible cut-off type emergency shut-off valve ； (3) Pressure cut-off type emergency shut-off valve ； (4) Pull-break type emergency shut-off valve ； (5) Electromagnetic cut-off type emergency shut-off valve.