Sewer gas Sewer gas Sewer gas is a complex mixture of toxic and nontoxic gases produced and collected in sewage systems by the decomposition of organic household or industrial wastes, typical components of sewage. Sewer gases may include hydrogen sulfide, ammonia, methane, esters, carbon monoxide, sulfur dioxide and nitrogen oxides. Improper disposal of petroleum products such as gasoline and mineral spirits contribute to sewer gas hazards. Sewer gases are of concern due to their odor, health effects, and potential for creating fire or explosions. Sewer gas is typically restricted from entering buildings through plumbing traps that create a water seal at potential
Gas attacks at Hulluch from whence the gas was being discharged. After thirty minutes, groups of German infantry about equipped with pistols and hand grenades, were seen heading for gaps in the British wire and were repulsed by rifle and machine-gun fire. At about the three mines were sprung and another bombardment was fired, before sending another gas cloud, which caused many casualties to a Black Watch company, whose commander had ordered them to remove their gas helmets after the first gas cloud, under the impression that the helmets were useless after one exposure to gas. Behind the second gas cloud, larger parties of