Abstract: The invention relates to the respiratory organs protection technical means that provide human with life support in the atmosphere unsuitable for breathing. Insulating breather with closed breathing mixture circulation loop (self-contained self-rescue, SCSR) is equipped with a cylinder (15) containing pressurized oxygen. The breather has increased effectiveness of the treatment of the exhaled gas mixture and improved quality of the inhaling gas mixture by using the breathing mixture circulation loop of the present invention and using means for simultaneous mechanical pressing on the breath-out bag (4) and the breath-in bag (8) and the additional cooling.