What is the detection and alarm value for chlorine gas?
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May I ask what the detection and alarm threshold for chlorine in the workshop is? 1mg/m3? ~0.3ppm? Can alarm sensors on the market achieve this level of precision? I work on safety facility design – what should be an appropriate amount?
Many alarm instruments cover a range of 0.1 to 50 ppm, and the threshold value can be set manually. Generally, it can be set according to the maximum allowable concentration of air in workshops specified in the \"Health Standards for Industrial Enterprise Design\", which is 1 mg/Nm3, equivalent to 0.3 ppm.
The alarm device is set at 1 ppm, and it is necessary to regularly check whether the concentration exceeds the maximum allowable level for workshop air specified in the \"Health Standards for Industrial Enterprise Design\", which is 1 mg/Nm3 (the alarm device indicates around 0.3 ppm).
For specific details, refer to the standards set out in the Occupational Exposure Limits for Hazardous Factors in the Workplace, GBZ2-2002
Conversion between concentration units ppm and mg/m3: Calculate using the following formula: mg/m3 = M/22.4 · ppm, where M is the molecular weight of the gas and ppm is the measured volume concentration. The molecular weight of chlorine gas is 70.91； According to GBZ 2.1-2007 Occupational Exposure Limits for Hazardous Factors in the Workplace – Part 1: Chemical Hazardous Factors, the maximum allowable concentration of chlorine gas in the air is 1 mg/m3. Substituting this into the formula, the volume concentration of chlorine found is 0.31 ppm, which is the set maximum limit. I searched for BC-2B type chlorine and chlorine dioxide detectors (chlorine leakage alarms). Sensitivity range: above 0 PPM ； (**Specified as 1PPM; adjustable from 1–5ppm) Operating environment: -5℃ to +40℃ ； Sensitivity: Less than 10 seconds (when chlorine concentration is greater than 0 PPM) ； Alarm method: Sound and light alarm ； Power supply: -220V 50HZ ； Power: 10W ； Dimensions: 280×195×78 (mm) Last edited by Striving for victory in solitude on 2009-3-15 09:15]
The standards are all from the 2007 version; they’re still considered \"outdated\". The moderator up above provided an accurate answer with detailed explanations – truly impressive. This post was last edited by sngqngx on 2009-3-15 at 14:27
GBZ 2.1-2007 Occupational Exposure Limits for Hazardous Factors in the Workplace – Part 1: Chemical Hazardous Factors; the OEL for chlorine is 1 mg/m3, which is equivalent to 0.34 ppm. According to the Design Code for Detection and Alarm of Flammable and Toxic Gases in Petrochemical Enterprises SH3063-1999, the alarm setting value for toxic gases should be less than or equal to 1 TLV; when it is difficult to prepare standard gases for testing, the alarm setting value can be below 2 TLV.