I’m an idiot. I should have consulted GIRM first.GIRM 69-71 deals with Prayers of the Faithful.
The Prayer of the Faithful
69. In the Prayer of the Faithful, the people respond in a certain way to the word of God which they have welcomed in faith and, exercising the office of their baptismal priesthood, offer prayers to God for the salvation of all. It is fitting that such a prayer be included, as a rule, in Masses celebrated with a congregation, so that petitions will be offered for the holy Church, for civil authorities, for those weighed down by various needs, for all men and women, and for the salvation of the whole world.67
- As a rule, the series of intentions is to be
For the needs of the Church;
For public authorities and the salvation of the whole world;
For those burdened by any kind of difficulty;
For the local community.
Nevertheless, in a particular celebration, such as Confirmation, Marriage, or a Funeral, the series of intentions may reflect more closely the particular occasion.
- It is for the priest celebrant to direct this prayer from the chair. He himself begins it with a brief introduction, by which he invites the faithful to pray, and likewise he concludes it with a prayer. The intentions announced should be sober, be composed freely but prudently, and be succinct, and they should express the prayer of the entire community.
The intentions are announced from the ambo or from another suitable place, by the deacon or by a cantor, a lector, or one of the lay faithful.68
The people, however, stand and give expression to their prayer either by an invocation said together after each intention or by praying in silence.
It appears to me that people from the pews can’t state their intentions out loud and the pew isn’t a suitable place, as it isn’t as prominent as an ambo or altar would be.