49 C.F.R. § 385.11

(a) The FMCSA will provide a motor carrier written notice of any safety rating resulting from a compliance review as soon as practicable, but not later than 30 days after the review. The notice will take the form of a letter issued from the FMCSA's headquarters office and will include a list of FMCSR and HMR compliance deficiencies which the motor carrier must correct.

(b) If the safety rating is “satisfactory” or improves a previous “unsatisfactory” safety rating, it is final and becomes effective on the date of the notice.

(c) In all other cases, a notice of a proposed safety rating will be issued. It becomes the final safety rating after the following time periods:

(1) For motor carriers transporting hazardous materials in quantities requiring placarding or transporting passengers by CMV—45 days after the date of the notice.

(2) For all other motor carriers operating CMVs—60 days after the date of the notice.

(d) A proposed safety rating of “unsatisfactory” is a notice to the motor carrier that the FMCSA has made a preliminary determination that the motor carrier is “unfit” to continue operating in interstate commerce, and that the prohibitions in § 385.13 will be imposed after 45 or 60 days if necessary safety improvements are not made.

(e) A motor carrier may request the FMCSA to perform an administrative review of a proposed or final safety rating. The process and the time limits are described in § 385.15.

(f) A motor carrier may request a change to a proposed or final safety rating based upon its corrective actions. The process and the time limits are described in § 385.17.