Mandatory machine voting was introduced by force of amendments to the election rules adopted by the previous, 45th National Assembly, which lasted less than one month. Under the Election Code, voting is only done using specialized machine voting devices. An exception is only made at polling stations with less than 300 voters, but also for mobile ballot boxes, at medical establishments or other specialized institutions, as well as on board vessels sailing under a Bulgarian flag. If unforeseen external circumstances occur and the machine voting is halted, voting shall continue using paper ballots. To provide for such a contingency more than 7 million paper ballots have been printed. /BGNES