【Daily Question】Question from Issue 20151013
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Participation reward: 2 Wealth. Reward for correct answer: 9 wealth. Regarding the description of protective ventilation equipment in civil air defense facilities, which of the following statements is incorrect? ( ) (A). An explosion-proof valve is a device designed to prevent shock waves from entering the underground shelter through ventilation openings. (B) The selection of an explosion-proof valve is determined by factors such as the resistance level of the structure and the required volume of air for ventilation. (C) An automatic overpressure exhaust valve can be used in ventilation systems with a resistance level of 0.25 MPa. (D) A sealed valve is a component used to switch between normal and combat mode in an underground shelter’s ventilation system; it can only be opened or closed, and cannot be used to adjust the volume of air flow. [Production and Management Division] Seeking moderators and technical discussants to join us
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Regarding the description of protective ventilation equipment in civil air defense facilities, which of the following statements is incorrect? (D) (A). An explosion-proof valve is a wave-damping device that prevents shock waves from entering the civil air defense facilities through ventilation openings. (B) The selection of an explosion-proof valve is determined by factors such as the resistance level of the facility and the required volume of fresh air. (C) An automatic exhaust valve designed to handle overpressures can be used in ventilation systems with a resistance level of 0.25 MPa. (D) A sealed valve is a component used to switch between normal and combat mode in civil air defense ventilation systems; it can only be opened or closed, and it cannot regulate the volume of air flow
D Hermetic valve: A specialized valve used to ensure the hermeticity of ventilation systems and prevent exposure to toxins; it is an essential control device for switching ventilation modes, and is available in both manual and manual-electric versions. The air volume can be adjusted.
Regarding the description of protective ventilation equipment in civil air defense facilities, which of the following statements is incorrect? ( ) (A). An explosion-proof valve is a wave-damping device that prevents shock waves from entering the civil air defense facilities through ventilation openings. (B) The selection of an explosion-proof valve is determined based on factors such as the resistance level of the facility and the required volume of air for ventilation. (C) An automatic overpressure exhaust valve can be used in ventilation systems with a resistance level of 0.25 MPa. (D) A sealed valve is a component used to switch between normal and combat mode in civil air defense ventilation systems; it can only be opened or closed, and cannot regulate the volume of air flow. The correct answer is D. Refer to page 331 of the textbook: An explosion-proof valve is a device installed outside ventilation openings that can be quickly closed when shock waves arrive; therefore, option A is correct. Article 5.2.10 of the Civil Air Defense Design Code, B is correct. According to page P331 of the textbook, the overpressure automatic exhaust valve can withstand shock wave pressures of 0.3 MPa; it can therefore be used in exhaust noise reduction systems with a resistance of 0.25 MPa, so option C is undoubtedly correct. A sealed valve is a device used to switch the ventilation mode of a protective ventilation system; it is a specialized valve designed to ensure the system remains sealed and free from toxic substances. Note that it refers to the switching between protection ventilation systems. Protection ventilation includes clean ventilation, isolation ventilation, and gas-filtering ventilation; it is the switching between these three methods, rather than the switching between normal conditions and wartime conditions. Under normal conditions, the ventilation system is isolated from the one used in wartime through protective sealed doors, rather than sealed valves. Therefore, D is incorrect; sealed valves, just like fire control valves, can have their opening degree adjusted, and can be closed completely when needed.
Regarding the description of protective ventilation equipment in civil air defense facilities, which of the following statements is incorrect? ( D )
Regarding the description of protective ventilation equipment in civil air defense facilities, which of the following statements is incorrect? ( D )
(A). The blast-proof valve is a wave-damping device that prevents shock waves from entering the underground shelter through ventilation openings.
Regarding the description of protective ventilation equipment in civil air defense facilities, which of the following statements is incorrect? ( D )
Regarding the description of protective ventilation equipment in civil air defense facilities, which of the following statements is incorrect? ( D )
Regarding the description of protective ventilation equipment in civil air defense facilities, which of the following statements is incorrect? (D) (A). An explosion-proof valve is a wave-damping device that prevents shock waves from entering the civil air defense facilities through ventilation openings. (B) The selection of an explosion-proof valve is determined by factors such as the resistance level of the facility and the required volume of fresh air. (C) An automatic exhaust valve designed to handle overpressures can be used in ventilation systems with a resistance level of 0.25 MPa. (D) A sealed valve is a component used to switch between normal and combat mode in civil air defense ventilation systems; it can only be opened or closed, and it cannot regulate the volume of air flow