(a) The stewards or racing judges may require an occupational licensee acting pursuant to the license to submit to a urine test or other non-invasive fluid test at any time while on association grounds.(b) A licensee who refuses to submit to such a test when requested to do so by the stewards or racing judges shall be suspended for at least six months. The stewards or racing judges shall revoke the license of a licensee who refuses to submit to a test for a second or subsequent time.