The first of the forms of Eucharistic Worship outside of Mass is Exposition. The introduction to this runs eleven sections, and is equivalent on a small scale to the GIRM. The Church frames the relationship between exposition and Mass:
82. Exposition of the holy eucharist, either in a ciborium or in a monstrance, leads us to acknowledge Christ’s marvelous presence in the sacrament and invites us to the spiritual union with him that culminates in sacramental communion. Therefore it is a strong encouragement toward the worship owed to Christ in spirit and in truth.
In such exposition care must be taken that everything clearly brings out the meaning of eucharistic worship in its correlation with the Mass. There must be nothing about the appointments used for exposition that could in any way obscure Christ’s intention of instituting the eucharist above all to be near us to feed, to heal, and to comfort Us.[Eucharisticum Mysterium 60]
Eucharisticum Mysterium 60 recommends exposition to follow the Mass, and that the host used be consecrated at that Mass. Rarely is a large church filled for exposition, though. When it’s not, I can see the value of providing for exposition in a small chapel. EM 60 also validates the notion of the Eucharist as a meal, but also touches upon the sacrament as a means of healing grace. Does exposition encourage these values?
More from Eucharisticum Mysterium. CS analysis was posted at this link.
83. During the exposition of the blessed sacrament, celebration of Mass in the body of the Church is prohibited.
In addition to the reasons given in no. 6, the celebration of the eucharistic mystery includes in a higher way that inner communion to which exposition is meant to lead the faithful.
If exposition of the blessed sacrament goes on for a day or for several successive days, it should be interrupted during the celebration of Mass, unless it is celebrated in a chapel separate from the area of exposition and at least some of the faithful remain in adoration.[Eucharisticum Mysterium 61]