The first commercially successful scuba sets were the Aqualung open-circuit units developed by Emile Gagnan and Jacques-Yves Cousteau, in which compressed gas (usually air) is inhaled from a tank and then exhaled into the water adjacent to the tank.
However, the scuba regulators of today trace their origins to Australia, where Ted Eldred developed the first mouth piece regulator, known as the Porpoise. This regulator was developed because patents protected the Aqualung’s double hose design. It separated the cylinder from the demand valve giving the diver air at the same pressure surrounding his mouth, not surrounding the tank.
The open circuit systems were developed after Cousteau had a number of incidents of oxygen toxicity using a rebreather system, in which exhaled air is reprocessed to remove carbon dioxide. Modern versions of rebreather systems (both semi-closed circuit and closed circuit) are still available today, and form the second main type of scuba unit, most commonly used for technical diving, such as deep diving.
Today, the dive industry is steadly taking shape. According to an article from IBISWorld, The industry will perform steadily over the next five years, with modest revenue growth and stable demand. Since the industry’s main customers are younger professionals, the rising unemployment rate hurt its performance during the past five years. However, improved employment, spending and travel rates will spur revenue growth over the next five years. Consumers will engage in relatively expensive leisure activities like scuba diving, bolstering demand for related instruction.
The industry worldwide totaling close to half a biliion dollar yearly in revenue, from more than 1600 businesses providing about 9000 employments, is becoming one of many top industry that will continue showing growth and potencial for years to come.