At the conclusion of the inspection, the FDA inspector will give the owner a FDA Form 483 which lists the firm, the dates of the inspection, and the observations made by the inspector(s).
FDA will then provide an initial classification of the inspection based on the observations noted in the inspection, the investigator’s report, and the FDA District review. There are three possible outcomes OAI, VAI, and NAI.
Official Action Indicated (OAI) classification occurs when significant objectionable conditions or practices were found and regulatory action is warranted to address the establishment’s lack of compliance with statute(s) or regulation(s).
Voluntary Action Indicated (VAI) classification occurs when objectionable conditions or practices were found that do not meet the threshold of regulatory significance. Inspections classified with VAI violations are typically more technical violations of the FDCA.
No Action Indicated (NAI) classification occurs when no objectionable conditions or practices were found during the inspection or the significance of the documented objectionable conditions found does not justify further actions.
Reference About FDA.