Systematic studies were carried out to investigate the explosion characteristics and morphology of the multicomponent explosive gas mixture (H₂, CO, CH₄ and Air). The explosive limits of concentration, explosive morphology, explosive pressure waveforms and their influence factors were investigated. The explosive danger degree, the flame spreading limit, the minimum ignition energy and other explosive characteristics of the multicomponent explosive gas mixture were determined by experiments. Based on the various explosive morphologies and their pressure waveforms obtained, a new scientific compartmentalization of explosive morphology for the multicomponent explosive gas mixture was proposed for the first time. Within the explosive limits, the explosive morphology can be further compartmentalized into four kinds of explosive morphologies (cold flame, deflagration, detonation and deflagration to detonation transition) and six explosive zones (the upper and lower cold flame zones, the upper and lower deflagration zones, the detonation zone and the lower deflagration to detonation transition zone). The different mechanisms for developing the pressure waves of the explosive morphology were explored. Such knowledge is valuable for further studying the relevant system of branched-chain explosion and developing the theory of branched-chain explosion. The explosive danger degree, the flame spreading limit, the minimum ignition energy and other explosive characteristics of the multicomponent explosive gas mixture were obtained, which are helpful for instituting the explosion-proof safety guidelines for the multicomponent explosive gas mixture discussed. This study also introduced the concept of “key components” and points out that it is the key components of H₂ and oxidant O₂ that ignite explosion. The references and methods for developing the explosion-proof safety guidelines were proposed. The results will be of significance in preventing accidents caused by mixture gas branched-chain explosion, giving directions to designing of explosion-proof electric equipment and fire arresters, supervising the application of the concepts of branched-chain burning and branched-chain explosion to practice.

Key words: branched chain explosion, explosive limit of concentration, explosive morphology, explosive waveform, key component, the explosion-proof safety guideline