Can. 236

According to the prescripts of the conference of bishops, those aspiring to the permanent diaconate are to be formed to nourish a spiritual life and instructed to fulfill correctly the duties proper to that order:

1/ young men are to live at least three years in some special house unless the diocesan bishop has established otherwise for grave reasons;

2/ men of a more mature age, whether celibate or married, are to spend three years in a program defined by the conference of bishops.