Aqua Lung International

La Spirotechnique (later Aqua Lung/La Spirotechnique) is a large and well-known French firm which makes scuba gear, scuba sets and other breathing apparati. It started making the so-called Aqua-Lung regulators, like the CG45 (1945) and the Mistral (1955), among others.

In December 1942 the lieutenant de vaisseau (ship-of-the-Line Lieutenant) Jacques-Yves Cousteau met in Paris for the first time the engineer Émile Gagnan, employee at Air Liquide, a French company specialising in compressed gas. Because of severe fuel restrictions due to the German occupation of France, Gagnan had miniaturized and adapted to gas generators a Rouquayrol-Denayrouze-type regulator. Invented in 1860, adapted to diving in 1864 and mass-produced as of 1865 (when the Ministry of the French Navy ordered the first apparati), the Rouquayrol-Denayrouze regulator was being commercialized in 1942 by the Bernard Piel Company, who had inherited the patent. Cousteau requested Gagnan to adapt his new own regulator to diving and both men patented in 1943 the first modern diving regulator.

Early in 1943 Cousteau and Gagnan ordered Air Liquide to make at its factory in Boulogne-Billancourt two scuba set prototypes that Cousteau and Frédéric Dumas used to shoot the underwater film Épaves (Shipwrecks), directed by Cousteau the same year. They were the first modern diving regulators to be made.

In 1946 Air Liquide founded La Spirotechnique, its own division destined to conceive and mass-produce regulators and other diving equipment. Also in 1946 La Spirotechnique launched the CG45, the first modern regulator to be commercialized. The year 1946 represents thus the beginning of the popularisation of scuba diving.

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Wikipedia