Smog Checks for Fleet Vehicles: What You Need to Know

What you need to know about smog checks

Fleet management requires a lot of ongoing maintenance to keep vehicles in good working condition and to meet regulatory requirements. Smog checks, sometimes called emissions inspections or emissions tests, are one of the regular inspections you will encounter for your fleet vehicles.

Transportation accounts for 28% of greenhouse gas emissions, according to the Environmental Protection Agency. Smog checks aim to reduce those emissions to keep air pollution below certain levels. While these inspections are primarily designed to promote public health, smog checks can also act as milestones for vehicle maintenance. Vehicles that pass the test must be well maintained, which helps fleets reduce fuel and maintenance costs, vehicle downtime and fines.

What is a smog inspection? 

Smog inspections or smog checks are vehicle inspection and maintenance programs that identify vehicles with excess emissions so they can be properly repaired or retired. Smog checks inspect a vehicle’s emissions-control equipment and systems to measure the amount and type of pollutants the vehicle emits.

These inspections are typically run by state governments and carried out by approved inspectors at select sites. Some states require them, some don’t, and some require inspections only in certain counties. Your state might even have a separate program for heavy-duty vehicles with a unique testing process and frequency.

How often do you need a smog check? 

Smog check or emissions testing requirements differ based on state and local laws, but many states require them annually or biennially (every other year) as part of the vehicle registration or registration renewal process, as well as when vehicles are first registered or change owners. Requirements are typically based on vehicle type, age and operating area.

It’s important to keep in touch with your area’s motor vehicle authority (such as a department, division or office of motor vehicles) so you know if you are in compliance with all emissions-related regulations.

How should I prepare my fleet vehicles for a smog inspection?

A good way to prepare your fleet vehicles for a smog check is to perform regular maintenance. This includes getting regular oil changes, tune-ups, filter changes and taking your vehicle in for repairs as soon as the “check engine” light comes on. 

Companies can make it easier to stay on top of smog check requirements using the right fleet management software. Fleet managers can receive alerts when maintenance is due, flag potential problems using vehicle diagnostics and run emissions reports.

{{Mid-CTA}} Fleet managers who use fleet management software even see significant cost savings on maintenance when using this kind of software. [2025 Fleet Technology Trends Report link TBD]

What should you expect during a smog check?

Smog checks typically involve visual, functional and emissions inspections.

• Functional: This is where inspectors plug into your vehicle’s on-board diagnostic (OBD) system to get a picture of your vehicle’s health and how well the systems work in managing emissions.
• Emissions: Using an exhaust gas analyzer, inspectors will check your vehicle’s exhaust for smog-causing pollutants including hydrocarbons, carbon monoxides and nitrogen oxides to see if they fall above or below certain thresholds.
• Visual: Inspectors will physically look at the vehicle to see if it has proper, working emissions-control equipment and systems. They will also look for an excess of smoke—black or white—that your car produces while running.

Smog inspections are performed at select sites by approved administrators. Typically, these are auto repair or oil change shops, but there may be other options for government fleets or heavy-duty vehicles. To find a site or station that performs smog checks, search online or call your state’s motor vehicle authority.

How long do smog checks take to complete? 

Smog check times vary, but they are typically a quick process. Most inspections take about 15 minutes, but this can depend on vehicle age, type and condition—and how long you must wait for an inspection. You can call ahead to find out how long the check takes, current wait times, or if the site will help you schedule multiple vehicles at one time.

What do you need to do if your vehicle passes the smog check?

If your vehicle passes the smog check, your inspector will present you with a vehicle inspection report and electronically inform the motor vehicle authority in your state that you passed. This is sometimes called a “smog certificate.” You typically do not have to do anything else to notify the department of your passing status—and if you are completing an emissions test as part of your vehicle’s registration or registration renewal process, you may proceed with that process. 

What if your fleet vehicle fails the smog check? 

If a fleet vehicle fails the smog check, the inspector will explain the emissions-related repairs you must make to gain compliance. After you make these repairs, you must get your vehicle re-inspected until it officially passes. In certain states, these repairs must be performed by a licensed station. 

You may also have the option to see a third party for a second opinion on your results. For example, in California this is called a smog check referee. These referees can assist you with inspecting unusual vehicles or locating hard-to-find emissions parts.

How can smog checks aid in efficient fleet management?

Maintaining your vehicles, particularly their emissions systems and parts, will make passing smog checks easier and more efficient. But there are more benefits to maintaining your vehicles in good working order:

• Better fuel economy: Passing a smog check indicates that your vehicles are running efficiently and can help reduce fuel costs.
• More effective maintenance: Smog checks may catch maintenance issues early on, alerting you to issues before they escalate and become breakdowns, downtime and more expensive repairs.
• Achieve ongoing compliance: Vehicles that have not completed required smog checks on time cannot be registered and are not road-legal. If you don’t pull those vehicles from the road, you can be ticketed and fined if you have not completed your check on time.
• Emphasize sustainability: From a branding perspective, focusing on ways to boost fleet sustainability shows your customers that you care about your fleet’s environmental impact as well as driver and public safety. 

Fleet management software offers a streamlined, efficient and cost-effective way to achieve all these goals. Fleet managers can stay on top of smog checks and other emissions regulations easily while reaping the benefits of proactive maintenance. Set up a demo today.

Verizon Connect does not provide legal advice and shall have no liability whatsoever for any damages that arise from, or are connected with, your use of this blog. This material has been prepared for informational purposes only, and is not intended to provide, and should not be relied on for legal advice. You should consult your own legal advisors to seek the proper advice with reference to any compliance-related information in this blog.