49 CFR §674.29

1. (a)In determining whether to approve a Public Transportation Agency Safety Plan for a rail fixed guideway public transportation system, an SSOA must evaluate whether the Public Transportation Agency Safety Plan is compliant with 49 U.S.C. 5329(d) and part 673 of this chapter; is consistent with the National Public Transportation Safety Plan; and is in compliance with the SSO program standard set by the SSOA.
2. (b)In an instance in which an SSOA does not approve a Public Transportation Agency Safety Plan, the SSOA must provide a written explanation and allow the RTA an opportunity to modify and resubmit its Public Transportation Agency Safety Plan for the SSOA's approval.