R.I. Gen. Laws § 17-15-18: Apportionment of voting booths and optical scan precinct count units.

(a) The apportionment of voting booths for the primary election of each political party shall, as far as possible, be on the same basis as for general elections, except that the determination shall be made with reference to the average number of votes received by the candidates of each party at the preceding general election.

(b) Unless otherwise prescribed by the board of elections, one optical scan precinct count unit shall be programmed and provided for each voting district. In no event shall there be less than one optical scan precinct count unit for each voting district.