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2 September 2015 Last updated at 00:34 BST
They work long hours and usually take home less than $1,000 (Â£650) a month, most of which is sent back to their families.
Many are from cricket-mad India and Bangladesh, and they like nothing more than to spend their one precious day off playing cricket.
Now they have a cricket league of their own, as Papan Chandradas, a Bangladeshi worker and the captain of one of the teams, explains.
Produced by Timothy McDonald
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