(b) The foundation shall have 15 calendar days after receipt of a proper invoice at its designated payment office to notify the contractor of certain facts and conditions, including but not limited to those listed below, which in the opinion of the foundation, justify a delay of the prompt payment:

1. (1) there is a defect in the delivered goods, property or services;
2. (2) there is a defect in the invoice;
3. (3) there are suspected improprieties of any kind;
4. (4) prior to payment a statutory or contractual provision requires an inspection period or an audit to determine the resources applied or used by the contractor in fulfilling the contract terms;
5. (5) a proper invoice must be examined by the Federal government prior to payment;
6. (6) the foundation is prevented from making payment by reason of the existence of a lien attachment, or other legal restriction;
7. (7) the necessary State government appropriation required to authorize payment has yet to be enacted; or
8. (8) the contractor has failed to submit a proper invoice or other material in accordance with the terms of the contract. Any time taken to satisfy or rectify any of the above facts or conditions or any delay in submission of required material shall extend the date by which prompt payment must be made by an equal period of time.