Definition and numbering standards for Chemical Oxygen Self Rescuer

The Chemical Oxygen Self Rescuer  is a self-rescuer that isolates the air in the disaster area and can generate oxygen through chemical reaction. It uses potassium superoxide or sodium superoxide to react with carbon dioxide to generate oxygen to achieve self-rescuing.
The models of Chemical Oxygen Self Rescuer allowed by the state are ZH-30 and its variants (different materials have different tail numbers), ZH-45 and its variants, and ZH-60 and its variants.

Chemical Oxygen Self Rescuer with other numbers must have the above ZH related numbers and current numbers on the corresponding safety labels.