Abstract: A regulating apparatus for supplying a receiving unit with gas from a pressurized source comprises a valve piloted by a two-position solenoid valve controlled by a computer which receives data from pressure sensors. When used as a demand breathing regulator, the apparatus has a main valve for connecting a source of pressurized breathing gas and a breathing mask and a pilot diaphragm subjected to the pressure in the mask. A sensor senses the movements of a diaphragm or the pressure in the mask. A solenoid valve controls the pressure in a pilot chamber of the main valve.