Alarm value of hydrogen sulfide gas detector
Alarm value of hydrogen sulfide gas detector Hydrogen sulfide is an important chemical raw material, which is very harmful to the human body and the environment. It will not only cause personnel poisoning, but also cause fire and explosion accidents. Deaths and fire accidents caused by hydrogen sulfide are not uncommon. In the environment where hydrogen sulfide exists, its concentration must be detected. So how to set the alarm value of hydrogen sulfide gas detection alarm, let's take a look below.
The lower explosive limit (LEL) and upper explosive limit (UEL) of hydrogen sulfide are 4% and 44%, respectively, and the occupational exposure limit (OEL) is 10mg/m³. In the "GBT50493 Petrochemical Combustible Gas and Toxic Gas Detection and Alarm Design Standard", it is stipulated that a single-component gas medium that is both flammable gas and toxic gas should be equipped with a toxic gas detector. According to regulations, the first-level alarm setting value of toxic gas should be less than or equal to 100% OEL, and the second-level alarm setting value should be less than or equal to 200% OEL; that is to say, the first-level alarm value of the hydrogen sulfide gas detector should be less than 10mg /m³, the secondary alarm value should be less than 20mg/m³.
There are many occasions where hydrogen sulfide exists, such as oil extraction and refining process; mining and metal smelting processing; low-temperature coking of coal; rubber, leather, dye, sugar and other processes; Hydrogen sulfide may be produced during remediation; in the process of sewage treatment in sewage treatment plants; in volcanic eruptions, etc. Hydrogen sulfide is a strong neurotoxin, which has a strong stimulating effect on mucous membranes, and can cause eye irritation, photophobia, stinging pain, blurred vision, tearing and other symptoms; respiratory irritation can cause cough, itchy throat, dyspnea, In severe cases, pulmonary edema may occur. In addition, the nervous system will be damaged, symptoms such as dizziness, headache, drowsiness, and coma will appear, and in serious cases, sudden death will occur directly.
