R.I. Gen. Laws § 45-21.2-19
Any person who, from January 1, 1943, and thereafter, was a volunteer member and/or a member of the call system of the East Greenwich fire district, is entitled to credit as service for the various purposes of the retirement system for one year for every three (3) years served as a volunteer and/or call fire fighter of the district; provided, that the person pays into the retirement system in the manner, at the times and in an amount that the retirement board may prescribe, (1) for purchases requested on or before June 30, 2012, an amount based upon his or her compensation, which for the purposes of this section is deemed to be in an amount of not less than three hundred dollars ($300) annually, for the last year of each three (3) year period at the time of purchase of the credit, and regular interest as defined in chapter 8 of title 36; and (2) for purchases requested on or after July 1, 2012, the full actuarial cost of the time being purchased.
R.I. Gen. Laws § 45-21.2-19