History of scuba diving the high number of recreational scuba accidents. this started with informal training and led to the creation of training and certification agencies. BS-AC was formed in 1953, CMAS in 1959, NAUI in 1960 and PADI in 1966. The sport of scuba diving had its roots among the multitude of small enthusiastic snorkelling and spearfishing clubs in the decades just before and after the Second World War. After the invention of the "aqualung" by Cousteau and Gagnan, the first commercially marketed underwater breathing apparatus became available for sale for sporting purposes in the late 1940s. In 1951, Jim Auxie Jr and
Scuba set limited the depth at which they could be used due to the risk of convulsions caused by acute oxygen toxicity. Although a working demand regulator system had been invented in 1864 by Auguste Denayrouze and Benoît Rouquayrol, the first open-circuit scuba system developed in 1925 by Yves Le Prieur in France was a manually adjusted free-flow system with a low endurance, which limited the practical usefulness of the system. In 1942, during the German occupation of France, Jacques-Yves Cousteau and Émile Gagnan designed the first successful and safe open-circuit scuba, known as the Aqua-Lung. Their system combined an improved demand