(b) Upon said certificate becoming effective, said special justice shall be subject to the following provisions:

1. (1) he shall devote full-time during ordinary business hours to the duties of his office, and shall not engage directly or indirectly in the practice of law;
2. (2) he shall be paid the salary provided for justices of the trial court who are required to devote full-time to their duties, said salary to be paid from the same sources and in the same manner as the salary of other justices of the district courts, and travel and expense allowances to the same extent as is provided for justices of the district courts;
3. (3) he shall sit by assignments of the chief justice for the district court in the district court to which he was appointed, in district courts in the county in which the district court to which he was appointed is located or in which he resides or in a county adjacent to either of them, and, in instances where exigent circumstances require, in district courts in other counties, and he shall perform such other duties as are assigned him by said chief justice. He shall be assigned to sit as proximate as reasonably practicable to the district court to which he was appointed, consistent with the public interest in the effective administration of justice; and he shall sit in such other courts and in such manner as the law provides for justices and special justices of the district courts;
4. (4) except as otherwise provided in this section he shall have the same powers, duties, rights and privileges, including the power to hear and decide civil actions, as a justice of a district court who is required to devote full-time to his duties and who is not the administrative head of his court; and (5) as provided in the preceding section six, he shall be eligible to be a first justice.

(d) The provisions of section six with regard to vacation and sick leave, including the provisions relative to accumulation, shall be deemed applicable to all justices and special justices who serve full-time in accordance with the provisions of this section. During the calendar year in which his certificate is made effective a special justice shall be entitled to the number of absences for vacation and sick leave corresponding to the proportion of said year remaining after said certificate becomes effective.

Notwithstanding any provisions of the general laws to the contrary, (1) for the purposes of determining pension responsibilities a special justice appointed, or first appointed, as the case may be, to his office prior to January second, nineteen hundred and seventy-five who serves full-time in accordance with the provisions of this section shall not be subject to the provisions of section sixty-five D of chapter thirty-two; and (2) for purposes of determining the pension rights of a special justice who serves full-time in accordance with the provisions of this section any special justice may elect to waive the provisions of section sixty-five B of chapter thirty-two and his full-time service shall be deemed the service of a justice of a district court, other than the chief justice, and said special justice shall be entitled to the same credit for his part-time service, if any, as a special justice as is provided in section sixty-five A of chapter thirty-two for a justice of a district court who has previously served as a special justice; provided, however, that nothing herein shall be construed to alter the pension rights and responsibilities applicable to a special justice who does not file a certificate under the provisions of this section.