Illinois contractors and subcontractors must keep accurate records for at least 3 years showing the name, address, telephone number, social security number, classification/occupation, hourly wages (including itemized hourly cash and fringe rates), hours worked each day, gross and net weekly wages (itemizing deductions) for each laborer, worker and mechanic employed on public works. The records shall be open at all reasonable hours to inspection by the public body awarding the contract, and the Department of Labor. The public body and the Department of Labor may also subpoena the production of all books, records, and other evidence related to an investigation or hearing. For more information, click here 820 ILCS 130/5 and 10.