Gas control apparatus

A gas control apparatus includes an upper housing to which a second piezoelectric pump is joined, a lower housing to which a first piezoelectric pump is joined, and a diaphragm. The upper housing includes a discharge hole through which gas is discharged. The lower housing includes introduction holes through which gas is introduced, an opening, a first valve seat, a second valve seat, and a third valve seat. The diaphragm is sandwiched between the upper housing and the lower housing, and is fixed to the upper housing and the lower housing so that the diaphragm contacts the first valve seat, the second valve seat, and the third valve seat. The diaphragm divides an inner space of the upper housing and the lower housing to define valve chests together with the upper housing and the lower housing.