A humidification assembly configured to humidify the pressurized respiratory gas from a respiratory ventilation apparatus, the humidification assembly including a liquid chamber configured to accommodate one or more liquids, the liquid chamber including a shell, a tank, a tank cover, a humidification assembly gas inlet port configured to introduce the pressurized respiratory gas, via a first gas passage, into the tank, wherein the first gas passage includes an output port, and a humidification assembly gas outlet port configured to introduce the humidified and pressurized respiratory gas, via a second gas passage back into a main body of the respiratory ventilation apparatus, wherein the second gas passage includes an input port, wherein the shell is connected and/or connectable to the tank and/or to the tank cover, and the shell is arranged pivotally relative to the tank, wherein the humidification assembly gas inlet port of the liquid chamber and/or the humidification assembly gas outlet port of the liquid chamber are set on a first side surface of the shell of the liquid chamber, wherein the output port of the first gas passage for connecting the first gas passage with the tank and/or the input port of the second gas passage for connecting the second gas passage with the tank are set inside the shell of the liquid chamber, wherein the output port of the first gas passage faces a second side surface of the shell of the liquid chamber, and the input port of the second gas passage faces a third side surface of the shell of the liquid chamber, characterized in that the second side surface of the shell of the liquid chamber is opposite to the third surface of the shell of the liquid chamber. the humidification assembly including a liquid chamber configured to accommodate one or more liquids, the liquid chamber including a shell, a tank, a tank cover, a humidification assembly gas inlet port configured to introduce the pressurized respiratory gas, via a first gas passage, into the tank, wherein the first gas passage includes an output port, and a humidification assembly gas outlet port configured to introduce the humidified and pressurized respiratory gas, via a second gas passage back into a main body of the respiratory ventilation apparatus, wherein the second gas passage includes an input port, a shell, a tank, a tank cover, a humidification assembly gas inlet port configured to introduce the pressurized respiratory gas, via a first gas passage, into the tank, wherein the first gas passage includes an output port, and a humidification assembly gas outlet port configured to introduce the humidified and pressurized respiratory gas, via a second gas passage back into a main body of the respiratory ventilation apparatus, wherein the second gas passage includes an input port, wherein the shell is connected and/or connectable to the tank and/or to the tank cover, and the shell is arranged pivotally relative to the tank, wherein the humidification assembly gas inlet port of the liquid chamber and/or the humidification assembly gas outlet port of the liquid chamber are set on a first side surface of the shell of the liquid chamber, wherein the output port of the first gas passage for connecting the first gas passage with the tank and/or the input port of the second gas passage for connecting the second gas passage with the tank are set inside the shell of the liquid chamber, wherein the output port of the first gas passage faces a second side surface of the shell of the liquid chamber, and the input port of the second gas passage faces a third side surface of the shell of the liquid chamber, characterized in that the second side surface of the shell of the liquid chamber is opposite to the third surface of the shell of the liquid chamber.