On March 20, 2018, the Federal Highway Administration (FHWA) issued Interim Approval (IA-21) for the optional use of Rectangular Rapid-Flashing Beacons (RRFB). Since IA-21 is regarding the use of an effective pedestrian safety countermeasure and is very similar to the recently terminated IA-11, Caltrans has expedited the process of requesting approval of IA-21 and has requested a statewide blanket approval regarding IA-21 from FHWA on March 22, 2018. FHWA is in the process of reviewing the request, and should provide the statewide blanket approval within the next few weeks.
Read the full Interim Approval (IA-21) Memorandum and Frequently Asked Questions related to IA-21.
FHWA approval status and additional information can be found at FHWA Interim Approvals Status in California.