On September 2, 2011, the NRC issued a Notice of Violation to William Beaumont Hospital for a Severity Level III violation involving the failure to develop written procedures to provide high confidence that each administration was in accordance with the written directive as required by 10 CFR 35.41(a). Specifically, as of May 5, 2011, the licensee's written procedures for yttrium-90 treatments did not specify how personnel should administer a treatment using a fine bore catheter and a high concentration of microspheres in order to prevent blockage within the catheter.