A friend of mine has been asked to help with a small conference where there will be Eucharistic Adoration. We were discussing the venue and she reminded me of a few rules which were set out by the Vatican a long time ago, 1970s, regarding Adoration. Also, recently, since the reign of Pope Benedict XVI, there have also been amendments. I shall try and find those when I have time. Here are the basic rules. There are different rules for Perpetual Adoration, which is not the subject of this post. I merely highlight some. Parishioners are not to deal with the Monstrance at all. I shall have several posts on this, including the entire document from the Bishops of England and Wales.
From The Congregation of Divine Worship EUCHARISTIAE SACRAMENTUM
For exposition of the blessed sacrament in the monstrance, four to six candles are lighted, as at Mass, and incense is used. For exposition of the blessed sacrament in the ciborium, at least two candles should be lighted and incense may be used.
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.
The following form of simple reposition may be observed: the priest or deacon, vested in an alb, or a surplice over a cassock, and a stole, replaces the blessed sacrament in the tabernacle after a brief period of adoration and a prayer said with those present. The exposition of the blessed sacrament may take place again, in the same manner and at a scheduled time
The ordinary minister for exposition of the eucharist is a priest or deacon. At the end of the period of adoration, before the reposition, he blesses the congregation with the sacrament.
In the absence of a priest or deacon or if they are lawfully impeded, the following persons may publicly expose and later repose the eucharist for the adoration of the faithful:
a. an acolyte or special minister of communion;
b. upon appointment by the local Ordinary, a member of a religious community or of a pious association of laymen or laywomen which is devoted to eucharistic adoration.
Such ministers may open the tabernacle and also, as required, place the ciborium on the altar or place the host in the monstrance. At the end of the period of adoration, they replace the blessed sacrament in the tabernacle. It is not lawful, however, for them to give the blessing with the sacrament.
92. The minister, if he is a priest or deacon, should vest in an alb, or a surplice over a cassock, and a stole. Other ministers should wear either the liturgical vestments that are used in the region or the vesture that is befitting this ministry and is approved by the Ordinary.
The priest or deacon should wear a white cope and humeral veil to give the blessing at the end of adoration, when the exposition takes place with the monstrance; in the case of exposition in the ciborium, he should put on the humeral veil.