Combustible gas installation
Thread Content
6.1.1 For detectors used to detect flammable gases or toxic gases that are heavier than air, their installation height should be between 0.3 and 0.6 meters above the floor (or floor slab). Note: Gases with a density greater than 0.97 kg/m3 (under standard conditions) are considered heavier than air ； Gases with a density of less than 0.97 kg/m3 (under standard conditions) are considered lighter than air. 6.1.2 For detectors used to detect flammable gases or toxic gases that are lighter than air, their installation height should be 0.5 to 2 meters above the source of emission. 6.1.3 The detector should be installed in a location free from impacts, vibrations, and strong electromagnetic interference, with a clear space of at least 0.3 m surrounding it. The density of carbon monoxide under standard conditions is 1.25 kg/m3, but in reality it is lighter than air. I would appreciate it if experts or moderators could explain how the 0.97 standard was determined. :)
The last edit to this post was made by zhy809078 on 2011-9-7 at 17:12. 28/29 = 0.97 refers to the density relative to air
Reply to 2# zhy809078: What is 26 again?
Reply to 3# Shouhou: It’s 28, the molecular weight of CO
The main question now is: why is 0.97 KG/M3 considered heavier than air, when the density of air is 1.30 KG/M3?
The above standard is derived from the \"SH3063-1999 Design Code for Detection and Alarm Systems of Flammable and Toxic Gases in Petrochemical Enterprises\"