呼吸阀是安装石油化工固定在储罐上的通气装置，以防止罐内超压或超真空使储罐遭受损坏，起阻止外界火焰传入，减少罐内液体挥发损耗的作用。

根据国家《石油化工防火规范》GB50160的规定：“甲、乙类液体的固体拱顶罐，应设阻火器和呼吸阀；为了满足这一要求，我厂于86年始就与中石化北京设计共同研制开发了全天候防火呼吸阀完整体系。具有造型科学新颖、规格型号齐全、结构紧凑、重量轻、通气量大、泄露小等特点。产品结构有呼吸型、单呼型、单吸型、异径型、夹套型。各种结构形式均可配备阻火器，也可配上所需的呼、吸端连接管，同时对油品、化工品食品不同介质的储罐采用不同材质制造，满足各类储运系统上工艺要求。产品先后经中国石油化工总公司、中国石化北京设计院，科学技术成果鉴定（92）中石化视鉴字01号、（95）BDI鉴字01号，并获：得中国石化进步三等奖”。

Breathing valve is installed Petrochemical fixed ventilation device in a tank, in order to prevent the tank overpressure or vacuum in the tank is damaged, preventing the external flame into the tank, reduce liquid volatilization loss function.

According to the regulations of the state "standard" fire petrochemical GB50160: "solid vault tank a, B liquid, should set the flame arrestor and breather valve; in order to meet this requirement, I plant in 86 years before and Sinopec Beijing design developed all-weather fire breathing valve complete system. Has the characteristics of other scientific novelty, the specification model is complete, compact structure, light weight, ventilation volume, leakage etc.. Product structure is breathing type, single call type, single suction type, reducing type, with jacket. Various structural forms can be equipped with a flame arrester, may also be required with the call, suction end connecting pipe, oil, chemicals and tank on the food of different medium with different material, fully meet the various requirements of the storage and transportation system technology. The product has the Sinopec Beijing Design Institute of China Petroleum & Chemical Corporation,, identification of scientific and technological achievements (92) treated with Sinopec No. 01, (95) BDI in 01, and won the three prize: Sinopec progress".