This self-rescuer adopts a circular breathing mode, using Ca(OH)₂ to absorb CO₂. Residual oxygen and decompressed oxygen enter the airbag for breathing. Compared with reciprocating breathing, it features lower resistance, no dust inhalation, lower inhalation temperature and higher comfort. With an advanced decompression principle and integrated gas circuit, it is compact, lightweight and reliable. It provides three oxygen supply modes: quantitative, automatic and manual, with two adjustable quantitative flow rates for evacuation and waiting for rescue. It is easy to fill oxygen, load absorbent, maintain and repair, and is reusable with high cost performance.