Segmentation by type dissects the Closed‑Circuit SCBA market into distinct technological families that influence unit cost, performance, and end‑user adoption. The primary classification distinguishes pure‑oxygen rebreathers, which recycle exhaled oxygen using a chemical scrubber and dominate the market due to their simplicity and reliability in short‑duration, low‑depth operations. Mixed‑gas rebreathers incorporate nitrogen or helium blends, expanding operational depth and duration for military and specialized industrial tasks, and thus capture a growing niche share. A third emerging family, hybrid systems, combine open‑circuit and closed‑circuit modes, offering flexibility for users who alternate between high‑intensity bursts and prolonged low‑intensity work. Within each family, form‑factor variations—back‑mounted, front‑mounted, and belt‑mounted units—further segment the market by ergonomics and task‑specific requirements. These type distinctions shape procurement decisions and, when aggregated, reflect the comprehensive market taxonomy of Closed‑Circuit SCBA devices.