Intellectually disabled workers who were paid as little as $1 an hour will have to waive their right to make discrimination claims if they accept a government payment equivalent to 50 per cent of what they are owed.

Legislation to set up the scheme passed the Senate on Monday with the support of crossbench senators Nick Xenophon, Bob Day, David Leyonhjelm, John Madigan, Ricky Muir and Zhenya "Dio" Wang.

Senators Bob Day, Nick Xenophon, David Leyonhjelm and John Madigan. Credit:Alex Ellinghausen

The Abbott government announced the payment scheme proposal last year after law firm Maurice Blackburn lodged a class action to recover lost wages for more than 10,000 workers.

The wages of these workers were calculated using the Business Services Wage Assessment Tool, which the Federal Court has ruled discriminated against people with intellectual disability.