Catechism of the Catholic Church §1669 — excerpt
Sacramentals derive from the baptismal priesthood: every baptized person is called to be a "blessing," and to bless. Hence lay people may preside at certain blessings; the more a blessing concerns ecclesial and sacramental life, the more is its administration reserved to the ordained ministry (bishops, priests, or deacons).
This translation is under copyright, so only the cited words are quoted here. Follow the link for the full text. Translation: English translation of the Catechism of the Catholic Church, 2nd ed. (Libreria Editrice Vaticana), as posted at vatican.va.
Also cites: SC 79 · CIC, can. 1168 · De Ben 16, 18