Truck Emissions & Clean-Truck Rules by State
California's CARB Clean Truck Check that hits out-of-state trucks too, the Advanced Clean Trucks adopter states, and the many states on federal EPA rules only. Keep your DPF and DEF working. Covers all 50 states and DC. Reference only, not legal advice.
1Clean Truck Check (CA)
11ACT adopters
EPAMost states
51Jurisdictions
01
The honest picture
Federal by default, California by exception
For most of the country, truck emissions are a federal EPA matter and there is no separate state program to worry about. The big exception is California, whose CARB Clean Truck Check reaches out-of-state trucks that run in the state. A group of states adopted the Advanced Clean Trucks sales rule, which binds manufacturers, not you at roadside. One rule holds everywhere: your DPF and DEF are federal equipment, so keep them working and never delete them.
02
By state
Emissions rules for all 50 states and DC
Tap a state for its program, the actual rule, the penalty, and the citation.
| State | Program | Rule |
|---|---|---|
| Alabama AL | Federal EPA only | No state heavy-duty diesel emissions inspection |
| Alaska AK | Federal EPA only | No state heavy-duty diesel emissions inspection |
| Arizona AZ | Clean Truck Check | Not an ACT state |
| Arkansas AR | Federal EPA only | Federal EPA standards only |
| California CA | Clean Truck Check | Clean Truck Check |
| Colorado CO | Clean Truck Check | ACT adopter, but that is a manufacturer ZEV sales quota |
| Connecticut CT | Federal EPA only | No heavy-truck emissions inspection program |
| Delaware DE | Federal EPA only | Federal EPA engine standards only for heavy trucks |
| District of Columbia DC | Federal EPA only | Federal EPA engine standards only for heavy trucks |
| Florida FL | Federal EPA only | No emissions inspection; Florida ended its program July 1, 2000 |
| Georgia GA | Federal EPA only | No heavy-truck emissions test |
| Hawaii HI | Federal EPA only | No emissions testing of any kind; Hawaii has never run a smog or diesel emissions program |
| Idaho ID | Federal EPA only | Federal EPA standards only |
| Illinois IL | Clean Truck Check | Illinois runs a Diesel Emission Inspection Program: diesel trucks registered for gross weight over 16,000 lb, two model years or older, in Chicago-area and Metro-East counties must pass an annual emissions inspection, and Illinois State Police can spot-test for excessive black smoke |
| Indiana IN | Federal EPA only | Federal EPA standards only; no state heavy-truck emissions test |
| Iowa IA | Federal EPA only | Federal EPA standards only |
| Kansas KS | Federal EPA only | Federal EPA standards only |
| Kentucky KY | Federal EPA only | No state heavy-truck emissions inspection |
| Louisiana LA | Federal EPA only | Federal EPA standards only for trucks |
| Maine ME | Federal EPA only | No state heavy-truck emissions inspection program |
| Maryland MD | ACT adopter | Maryland adopted the Advanced Clean Trucks rule |
| Massachusetts MA | ACT adopter | Adopted the Advanced Clean Trucks rule |
| Michigan MI | Federal EPA only | Federal EPA standards only |
| Minnesota MN | Federal EPA only | No state heavy-truck emissions program |
| Mississippi MS | Federal EPA only | Federal EPA standards only |
| Missouri MO | Federal EPA only | Federal EPA heavy-duty engine standards only; no state heavy-truck emissions inspection |
| Montana MT | Federal EPA only | Federal EPA standards only |
| Nebraska NE | Federal EPA only | Federal EPA standards only |
| Nevada NV | Federal EPA only | No emissions registration program for heavy trucks; diesels over 14,000 lb GVWR are exempt from Nevada's Clark/Washoe county smog check |
| New Hampshire NH | Federal EPA only | No state heavy-truck emissions inspection or reporting program |
| New Jersey NJ | ACT adopter | Adopted the Advanced Clean Trucks rule |
| New Mexico NM | ACT adopter | ACT adopter: a manufacturer ZEV sales quota phasing in from model year 2026, with no driver obligation |
| New York NY | ACT adopter | Adopted California's Advanced Clean Trucks |
| North Carolina NC | Federal EPA only | Federal EPA engine standards only for heavy trucks |
| North Dakota ND | Federal EPA only | Federal EPA standards only |
| Ohio OH | Federal EPA only | Federal EPA standards only; no state heavy-truck emissions test |
| Oklahoma OK | Federal EPA only | Federal EPA standards only |
| Oregon OR | ACT adopter | No periodic heavy-truck emissions inspection for interstate trucks |
| Pennsylvania PA | Federal EPA only | No driver-facing emissions inspection |
| Rhode Island RI | ACT adopter | Adopted California's Advanced Clean Trucks rule |
| South Carolina SC | Federal EPA only | No state emissions inspection of any kind |
| South Dakota SD | Federal EPA only | Federal EPA standards only |
| Tennessee TN | Federal EPA only | No state heavy-duty emissions program |
| Texas TX | Federal EPA only | Federal EPA heavy-duty engine standards only; no state heavy-truck emissions inspection |
| Utah UT | Federal EPA only | No state heavy-truck emissions inspection; diesel over 14,000 lb is exempt from county emissions testing |
| Vermont VT | ACT adopter | Adopted the Advanced Clean Trucks rule, but Governor Scott's Executive Order 04-25 |
| Virginia VA | Federal EPA only | Federal EPA engine standards only for heavy trucks |
| Washington WA | ACT adopter | No state heavy-duty diesel emissions inspection |
| West Virginia WV | Federal EPA only | Federal EPA engine standards only |
| Wisconsin WI | Federal EPA only | Federal EPA standards only; no state heavy-truck emissions test |
| Wyoming WY | Federal EPA only | Federal EPA standards only; no state emissions inspection of any kind |
Sources: CARB Clean Truck Check and Advanced Clean Trucks; EPA; state environmental / DEQ agencies. Last reviewed July 2026. Clean-truck programs and adoption dates change; confirm the current rule with the agency before you rely on it.
Truck Emissions FAQ
Does my state check truck emissions?
Most do not. The large majority of states have no state-specific heavy-truck emissions program and rely on federal EPA engine standards only. The clear exception is California, whose CARB Clean Truck Check requires periodic emissions compliance for most trucks over 14,000 pounds, including out-of-state trucks that drive in California. A handful of states run their own diesel opacity or smog checks, but for most of the country the rule is federal.
What is the CARB Clean Truck Check?
It is California's heavy-duty emissions program, the successor to the old Periodic Smoke Inspection Program. Most non-gasoline trucks over 14,000 pounds that operate in California must register in the CARB system, pass periodic emissions compliance testing, and stay reported. It applies to out-of-state carriers too if they drive in California. Roadside smoke and opacity testing backs it up, and non-compliance carries fines and registration holds.
What is the Advanced Clean Trucks (ACT) rule?
ACT is a manufacturer sales mandate, not a driver rule. It requires truck makers to sell a rising share of zero-emission trucks in states that adopt it. California wrote it and states like Oregon, Washington, New Jersey, New York, and Massachusetts adopted it, though some have delayed or paused enforcement. As a driver passing through, ACT does not fine you. It shapes what new trucks dealers can sell there.
Can I delete my DPF or DEF system?
No, not anywhere. The diesel particulate filter and diesel exhaust fluid systems on modern diesels are federal EPA equipment, and removing, disabling, or tampering with them is illegal under federal law in every state. It is not a state program, it is a federal one, and the penalties are steep. Keep the DPF and DEF working and topped off no matter which state you are running in.
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