45 C.F.R. § 75.432
A conference is defined as a meeting, retreat, seminar, symposium, workshop or event whose primary purpose is the dissemination of technical information beyond the non-Federal entity and is necessary and reasonable for successful performance under the Federal award. Allowable conference costs paid by the non-Federal entity as a sponsor or host of the conference may include rental of facilities, speakers' fees, costs of meals and refreshments, local transportation, and other items incidental to such conferences unless further restricted by the terms and conditions of the Federal award. As needed, the costs of identifying, but not providing, locally available dependent-care resources are allowable. Conference hosts/sponsors must exercise discretion and judgment in ensuring that conference costs are appropriate, necessary and managed in a manner that minimizes costs to the Federal award. The HHS awarding agency may authorize exceptions where appropriate for programs including Indian tribes, children, and the elderly. See also §§ 75.438 , 75.456 , 75.474 , and 75.475 .
45 C.F.R. §75.432