FRA

Not true about the FRA. If you read the regs very carefully, the FRA chooses not to exercise jurisdiction but, believe me, if there's an incident, the FRA will be front and center. BTW, it there is an incident, the regs would likely be changed.
49-CFR209
If a tourist operation off the general system is insular, FRA does (Note this is permissive) not exercise jurisdiction over it, and none of FRA's rules apply. If, however, such an operation is not insular, FRA exercises jurisdiction over the operation, and some of FRA's rules (i.e., those that specifically apply beyond the general system to such operations) will apply. For example, FRA's rules on accident reporting, steam locomotives, and grade crossing signals apply to these non-insular tourist operations (see 49 CFR 225.3, 230.2 amd 234.3), as do all of FRA's procedural rules (49 CFR parts 209, 211, and 216) and the Federal railroad safety statutes themselves.
In drafting safety rules, FRA has a specific obligation to consider financial, operational, or other factors that may be unique to tourist operations. 49 U.S.C. 20103(f). Accordingly, FRA is careful to consider those factors in determining whether any particular rule will apply to tourist operations. Therefore, although FRA asserts jurisdiction quite broadly over these operations, we work to ensure that the rules we issue are appropriate to their somewhat special circumstances.
It is important to note that FRA's exercise of its regulatory authority on a given matter does not preclude it from subsequently amending its regulations on that subject to bring in railroads originally excluded. More important, the self-imposed restrictions on FRA's exercise of regulatory authority in no way constrain its exercise of emergency order authority under section 203 of the Safety Act.