When rebreather use started becoming common at the beginning of the twenty-first century, it was the deep, cave, and wreck divers who adopted the new technology. This equipment allowed them to go deeper, penetrate farther, and conserve expensive helium breathing gas. Because they could push the envelope of diving beyond where they could with traditional OC (open circuit) scuba, they were willing to tolerate the numerous increased maintenance responsibilities (as well as pay the hefty price tag associated with rebreathers, often $10,000 to $15,000 or more). But times have changed.
