(a) Maximum suspension or debarment.--A government agency proceeding under its rules and regulations to exclude or render ineligible a person from participation in contracts or subcontracts based upon conduct prohibited by section 4503 (relating to prohibited activities) shall limit the exclusion or ineligibility to a period not to exceed the following:

(b) Lists of persons excluded.--A government agency that lets a contract by competitive bidding shall maintain a current list of persons excluded or ineligible by reason of suspension or debarment for participation in contracts or subcontracts with that agency and shall furnish a copy of the list upon request to a person considering the submission of a bid as a prime contractor or as a subcontractor.