What Is A CARB Compliant Catalytic Converter? (A Guide To Greener Driving)

For the uninitiated, a catalytic converter is basically the part of a car that’s responsible for changing harmful substances in a car’s exhaust gasses into less harmful substances.

What Is A CARB Compliant Catalytic Converter (A Guide To Greener Driving)

But crucially, not all catalytic converters are created equal. This article is all about CARB compliant catalytic converters and how they differ from other catalytic converters. And I will answer all of your most frequently asked questions on the subject along the way.

Let’s kick things off with the basics…

What Does CARB Stand For?

CARB stands for California Air Resources Board. The California Air Resources Board is basically the “clean air agency” of the government of California. They are charged with not only protecting the public from air pollution, but also taking action on climate change.

What Is A CARB Compliant Catalytic Converter?

A CARB Compliant Catalytic Converter is basically one that has been approved for sale by the California Air Resources Board. This means that if you plan on registering your vehicle in California, you must use a catalytic converter that meets CARB standards. 

But that doesn’t mean that CARB compliant catalytic converters are only available in the state of California. California may well have been the first to legislate for these catalytic converter requirements in the year 2009, but other states soon began to follow suit.

Toward the end of 2021, 15 US states had adopted California’s emission standards, including Colorado, Delaware, Maryland, New Jersey, Oregon, Rhode Island, Virginia, Washington DC, Connecticut, Maine, Massachusetts, New York, Pennsylvania, Vermont, and Washington.

Meanwhile, states such as New Mexico, Nevada and Minnesota were also working toward these standards.

What’s The Difference Between A CARB Compliant Catalytic Converter And A Regular Catalytic Converter?

Catalytic converters of any description are good news for the environment. Gas powered vehicles emit a lot of greenhouse gasses that are dangerous for our environment, and the catalytic converters found in such vehicles work to reduce this danger.

Catalytic converters can convert over 90 percent of hydrocarbons, nitrogen oxides and carbon monoxide from the engine into less harmful gasses, such as carbon dioxide, nitrogen, and water vapor.

But it has become clear that some catalytic converters are better than others. The benefit of a CARB compliant catalytic converter over previous versions is that they produce fewer harmful emissions than their predecessors, resulting in cleaner, safer air.

Before CARB compliance started coming into effect, the federal standards put in place for catalytic converters came from the EPA, where EPA stands for the Environmental Protection Agency.

EPA standards for catalytic converters came about shortly after catalytic converters started to become mainstream, as far back as the 1970s.

After 1975, if you ever needed your catalytic converter replaced in your vehicle, it would have been with an EPA approved catalytic converter. Any catalytic converter replacing a previous one is called an aftermarket catalytic converter.

EPA Vs CARB Compliant Catalytic Converters

The CARB emission standards for aftermarket catalytic converters are more elaborate than the EPA standards.

It is beyond the scope of this article to go into depth about the detail surrounding the two standards, but if you wish to find out more, check out the comparison table of the key requirements of CARB and EPA catalytic converters on this link.

But to summarize, as a general rule CARB standards are the better ones as far as environmental health, air pollution, global warming and climate change are concerned.

CARB compliant catalytic converters use a combination of a higher precious metal load together with an enhanced washcoat technology in order to meet the stricter CARB emissions standard.

How Do I Know Whether My Car Has A CARB Compliant Converter?

Every single batch of CARB compliant aftermarket catalytic converters has to be tested to confirm that it meets CARB standards, and the CARB holds a list of such catalytic converters on its website.

A CARB compliant catalytic converter will have a stamped number on its body to verify that it meets CARB emission standards.

This number (sometimes called EFN or test group number) will be listed on the CARB website for aftermarket catalytic converters, and that’s how you can verify that your converter is CARB compliant.

What Converter Do I Need?

If you have a gas powered vehicle or hybrid, you’re gonna need a catalytic converter. Different vehicles tend to require different catalytic converters.

To check whether your particular state requires CARB compliance for their converters, please refer to the legislation for your particular state, which you should find somewhere on their website, for the most up-to-date info on the subject.

What If I Use The Wrong Converter?

What Is A CARB Compliant Catalytic Converter (A Guide To Greener Driving) (1)

You don’t have to live in one of the states using CARB catalytic converter standards in order to have such a converter in your vehicle.

But if you live in one of the states that mandate the use of CARB compliant converters, and you only have an EPA standard catalytic converter, there may be consequences…

If you were to use the wrong converter, your check engine light should come on. You may also find some performance and efficiency issues. And more so over time.

Besides, every so often, most states require that vehicles undergo an emissions test, and if you were to use the wrong catalytic converter, your vehicle would fail the emissions test. At this point, you would have to invest in a better one.

Where Can I Get An Aftermarket CARB Compliant Catalytic Converter?

Would you believe it – they have CARB compliant catalytic converters readily available on Amazon – check out this link. Super convenient. Is there anything they don’t sell? 

Are EVs And Hybrids Better For The Environment Than A Regular Car With A CARB Compliant Catalytic Converter?

Vehicles that run only on electricity have zero tailpipe emissions, so these vehicles will never require a catalytic converter, CARB compliant or otherwise.

However, this is not the case for hybrid electric vehicles. If you were to own a hybrid vehicle, you would need a catalytic converter that meets your state’s emission standard requirements for occasions where you are relying on gas fuel rather than electricity.

So, electric only vehicles are better than traditional gas powered vehicles when it comes to tailpipe emissions, even if said gas powered vehicle has a CARB compliant catalytic converter installed.

However, it’s hard to say whether a hybrid vehicle would be better for the environment than a gas powered vehicle with a CARB compliant catalytic converter, because it depends on how much the gas engine would be used.

What’s more, this would be further complicated by the fact that hybrids may require more gas to move at the same speed, due to being heavier than a regular car because of the weight of the electric battery. But that can be mitigated by better fuel efficiency.

Wrap Up

So, if you’re in the market for a new car, and you’re thinking of getting a gas powered (or partly gas powered hybrid) then I would 100% go for one with a CARB compliant catalytic converter.

That way, you’d not only be helping the environment, but you’ll also be more likely to meet future emission standards.

However, I would argue that your best options are EVs or hybrids.

Jonathan Rice