Three School Committee candidates filed petitions requesting recounts of last Tuesday’s election, which was decided by a razor-thin margin of only six votes.

Officials will begin recounting votes this afternoon.

But commissioners are navigating uncharted waters in this recount. No clear recounting procedure has been established for a computerized voting system, which Cambridge adopted in 1997.

“We’ve never done one since we computerized,” said Theresa S. Neighbor, the executive director of the Cambridge Election Commission.

The most recent Cambridge recount occurred in the City Council election of 1993. Ninety-two votes—a wider margin than that in this year’s School Committee race—separated four candidates, and a recount did change the outcome of the election.

Susana M. Segat, who lost her seat on the School Committee by just six votes in the final election night tally, filed a petition yesterday contesting the election and requesting a recount.

Nancy Walser and Richard Harding, both declared winners on Tuesday, also made official requests for a recount, according to Neighbor. Ten candidates ran for six seats on the board. No other candidates filed recount petitions.

Only seven votes separated these three candidates in the last count on election night. Incumbent Walser received 2,220 votes, challenger Harding received 2,219 and Segat received 2,213, just missing the cutoff.

Candidates had until 5 p.m. yesterday to gather 50 signatures of registered Cambridge voters and file a petition requesting a recount with the Election Commission.

The Election Commission board will meet today at 2 p.m. to review the petitions and set a procedure for a recount.

According to Neighbor, the Election Commission decided that the recount will begin immediately after today’s board meeting. They expect that the process will begin around 2:30 p.m. and finish by the end of the day.