Evacuation central station, fitted with CGA type blowers performs operation for evacuating gas exhaled by the patients in the rooms and operating theaters for post operating awakening. Every plant is comprised of two side channel blowers that are shaped to a definite measurement as per the plant, to which it is connected. Each and every central station is dimensioned in order to fulfill the plant demands with a single blower so that a second blower is kept as backup in case of any emergency or damages. The electric card has been programmed for automatically exchanging blowers to maintain the same wear. The push button located on the distance alarm initiates the plant that maintain the depression degree required as per the selected model.