Second pressure limits in gaseous explosion regions: II. Experimental data on explosions of CO and CH4 with oxygen and air

Abstract The authors investigated the explosion limit as a function of the pressure (below about 120 cm Hg). With CH 4 ‐O 2 , CH 4 ‐air, CO‐O 2 and CO‐ air mixtures no shapes of explosion regions were found which were reminiscent of the lowpressure‐inflammation regions of these mixtures at higher temperatures. Though at the upper limit of mixtures with CO a “second pressure limit” was found, this was not at all comparable with the shape of the explosion region observed with H 2 ‐O 2 mixtures 1 ). The “second pressure limit” of CH 4 ‐air mixtures found by Lavrov and Bestchastny cannot have been an explosion limit, but must be attributed to secondary effects.