<P> On only four occasions have world record times for marathon running been set in Boston . In 1947, the men's record time set was 2: 25: 39, by Suh Yun - Bok of South Korea . In 1975, a women's world record of 2: 42: 24 was set by Liane Winter of West Germany, and in 1983, Joan Benoit Samuelson of the United States ran a women's world record time of 2: 22: 43 . In 2012 Joshua Cassidy of Canada set a men's wheelchair marathon world - record time of 1: 18: 25 . </P> <P> In 2007, astronaut Sunita Williams was an official entrant of the race, running a marathon distance while on the International Space Station, becoming the first person to run a marathon in space . She was sent a specialty bib and medal by the BAA on the STS - 117 flight of the Space Shuttle Atlantis . </P> <P> The race's organizers keep a standard time clock for all entries, though official timekeeping ceases after the six - hour mark . </P> <P> The Boston Athletic Association is a non-profit, organized sports association that organizes the Boston Marathon and other events . </P>

What is the course time limit for boston marathon
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