NSF may grant an exception permitting a debarred, suspended, or voluntarily excluded person, or a person proposed for debarment under 48 CFR part 9, subpart 9.4, to participate in a particular covered transaction upon a written determination by the agency head or an authorized designee stating the reason(s) for deviating from the Presidential policy established by Executive Order 12549 and § 620.200. However, in accordance with the President's stated intention in the Executive Order, exceptions shall be granted only infrequently. Exceptions shall be reported in accordance with § 620.505(a).