Title 23 › Chapter 1— FEDERAL-AID HIGHWAYS › § 166
Public authorities that run HOV lanes must set how many people need to be in a vehicle to drive there. Usually at least two people are required. Motorcycles and bicycles may use the lanes unless the authority proves to the Secretary that allowing them would be unsafe and the Secretary publishes that claim and takes public comment. Public transit vehicles can use the lanes if they are clearly marked, rules can be enforced, and over‑the‑road buses get the same access and terms as other public buses. Authorities may let other cars into HOV lanes if drivers pay a toll, enroll in a program, and the toll is collected automatically; the authority must use tolls to manage demand, enforce rules, and give over‑the‑road buses the same access. Before September 30, 2025, authorities may allow alternative fuel vehicles and the specific vehicles in Internal Revenue Code section 30D(d)(1) if enforcement procedures exist. Before September 30, 2019, authorities could allow EPA‑certified low‑emission, energy‑efficient vehicles that are labeled and pay any required toll. Blood transport vehicles moving blood between collection points and hospitals or storage may use the lanes if clearly identified. Tolls under these rules follow section 129 requirements, and if the lane is on the Interstate in a metropolitan planning area, the authority must consult the local planning organization about tolls. If an authority allows tolled or otherwise exempt vehicles, it must report to the Secretary that the lane is not already degraded and promise to monitor performance, enforce the rules, and limit or stop extra access if needed. A lane is “degraded” if it fails to meet the minimum average operating speed 90 percent of the time over a consecutive 180‑day period during weekday peak hours. Minimum average operating speed means 45 miles per hour when the speed limit is 50 miles per hour or higher, or no more than 10 miles per hour below the speed limit when the limit is under 50 miles per hour. If a lane becomes degraded, the authority has 180 days to send a plan to fix it (the Secretary will approve or disapprove within 60 days), must give yearly updates until fixed, and may face federal program sanctions unless the Secretary grants a waiver. The EPA must issue final rules for certifying and labeling low‑emission, energy‑efficient vehicles and the comparison methods within 180 days after the law is enacted. Definitions (one line each): alternative fuel vehicle — a vehicle that runs only on certain non‑petroleum fuels or electricity; HOV facility — a high‑occupancy vehicle lane or facility; low emission and energy‑efficient vehicle — a vehicle meeting Tier II emission levels and meeting specified fuel‑economy increases or an alternative fuel vehicle; over‑the‑road bus — the meaning used in the ADA; public authority — the State or local government (or entity it designates) that runs the HOV facility; public transportation vehicle — a vehicle that provides public or school transport and is owned, contracted, or licensed to do so.
Full Legal Text
Highways — Source: USLM XML via OLRC
Legislative History
Reference
Citation
23 U.S.C. § 166
Title 23 — Highways
Last Updated
Apr 5, 2026
Release point: 119-73not60