Rome ( CNN ) -- The Catholic cardinals gathered in Rome voted Friday to begin the secret election , or conclave , to elect a new pope next Tuesday afternoon , the Vatican said . The 115 cardinal-electors taking part in the conclave will enter the closed-door process after a morning Mass , the Vatican said . Only cardinals younger than 80 are eligible to vote . Selecting a pope : A digital interactive . The cardinals voted Friday morning to accept the letters of explanation of two cardinal-electors who are eligible to vote for the next pope but will not attend the conclave : Keith O'Brien of Scotland and Julius Riyadi Darmaatmadja of Indonesia . Darmaatmadja cited health reasons , and O'Brien cited personal reasons . Abuse victims ' group names preferred picks for new pope . O'Brien resigned in scandal last week after allegations that he made sexual advances toward young men studying to be priests . He apologized in a statement Sunday , saying , `` There have been times that my sexual conduct has fallen below the standards expected of me as a priest , archbishop and cardinal . '' Since Monday , the cardinals have been uniting for what are known as General Congregations , a series of meetings in which they discuss the issues facing the church . These include how to tackle the issue of child sex abuse by priests and a scandal over leaks from the Vatican last year that revealed claims of corruption within the Roman Catholic Church hierarchy . Opinion : How to pick a new pope . 'Move our church forward ' Some cardinals took to the Internet to make comments before Friday afternoon 's meeting that set the conclave date . Cardinal Peter Turkson of Ghana , viewed as one of about a dozen leading candidates to become pope , used Twitter to ask for prayers . `` Your continued prayers help us discern God 's will . To move our Church forward , '' wrote Turkson , who if elected would become the first African pontiff since Pope Gelasius I died more than 1,500 years ago . Another leading candidate , Cardinal Timothy Dolan of New York , told the people of his archdiocese in a blog post Friday that he misses New York and is sorry he wo n't be there on St. Patrick 's Day . `` Heartfelt thanks for your prayers ! We need them ! We feel them ! Keep them up ! '' Dolan wrote . Cardinal Roger Mahony , the retired archbishop of Los Angeles , also asked for prayers before Friday evening 's meeting . `` I hope we vote this evening to set the starting date for the Conclave ; preceded by the Mass to Elect a new Pope . Prayers , please ! ! '' he posted to Twitter . Electronic shield . The chimney used to send up the smoke signals that announce whether or not a new pope has been elected could be raised over the Sistine Chapel on Friday , said the Rev . Federico Lombardi , a Vatican spokesman . The voting takes place inside the chapel , beneath the ornate ceiling painted by Michelangelo . Opinion : What the next pope will face . The building was closed to tourists Tuesday and will remain so for the foreseeable future , the Vatican said . Work is well under way to transform it for the conclave . The cardinals have sworn an oath of secrecy . Nonetheless , the Vatican is taking no chances . An electronic shield will be put up around the conclave to prevent the use of mobile phones and other devices that might allow communication with the outside world . What Africans want from the next pope . However , Lombardi denied a report in the Italian media that the cardinals will be searched as they go in and out of the conclave . Among the things the cardinals have to do is draw lots for which rooms they get at the Casa Santa Marta , the hotel within the walls of Vatican City where they stay during the conclave . The hotel also contains a suite where the newly elected pope will live for a few weeks before moving to the papal apartments . The apartments were placed under seal after Benedict XVI left last week and must be renovated before the new pope can take up residence , the Vatican said . CNN 's Richard Allen Greene reported from Rome and Laura Smith-Spark wrote from London . Hada Messia in Rome and Jason Hanna in Atlanta contributed to this report .
Friday : Before Friday 's meeting , several cardinals took to the Internet to offer prayers . The secretive election for a new pope will start Saturday . The chimney that sends the signals will be raised over the Sistine Chapel on Sunday . The 115 cardinal - electors will draw lots for the rooms in which they reside during the conclave .