49 CFR §190.333

1. (a)General. Unless the Associate Administrator or the Chief Counsel otherwise specifies, no public hearing, argument, or other proceeding is held directly on a petition before its disposition under this section.
2. (b)Grants. If the Associate Administrator or the Chief Counsel determines that the petition contains adequate justification, he or she initiates rulemaking action under this subpart.
3. (c)Denials. If the Associate Administrator or the Chief Counsel determines that the petition does not justify rulemaking, the petition is denied.
4. (d)Notification. The Associate Administrator or the Chief Counsel will notify a petitioner, in writing, of the decision to grant or deny a petition for rulemaking.