The Copper-Free Brake Pad Law Explained

The "copper-free brake pad law" is really two state laws and a federal agreement that cap how much copper a brake pad is allowed to contain. California's SB 346 and Washington's Better Brakes Law both phased copper down to 5% by weight starting January 1, 2021, with a further cut to 0.5% by weight on January 1, 2025. A 2015 agreement between the EPA, state regulators and the brake industry extended those same limits to the rest of the country, so almost every pad sold in the United States today is built to the same copper ceiling no matter where you buy it.

What SB 346 and the Better Brakes Law actually require

California passed the Motor Vehicle Brake Friction Material Law (SB 346) in 2010. It set a two-stage copper limit: no more than 5% copper by weight in brake friction material sold in the state starting January 1, 2021, dropping to no more than 0.5% by weight starting January 1, 2025, with an inventory-depletion allowance that let already-manufactured 5% pads sell through for a short window. The same law also banned sale of pads containing more than trace amounts of cadmium, chromium-6 salts, lead, mercury and asbestiform fibers, effective back in 2014. Washington's chapter 70.285 RCW, the Better Brakes Law, followed the same two numbers and the same 2025 copper target, and required manufacturers to certify compliance through accredited third-party labs and mark packaging accordingly. Military vehicles, motorcycles and fully sealed brake systems are exempted in both states.

Rather than have every state write its own version, the U.S. EPA, the Environmental Council of the States and eight industry groups - including the Auto Care Association and the Motor & Equipment Manufacturers Association - signed a Copper-Free Brake Initiative memorandum of understanding on January 21, 2015. Manufacturers agreed to hit the same 5% and 0.5% copper targets nationwide, test alternative friction materials, and report their progress, which is why a pad bought in Ohio meets the same copper ceiling as one bought in California even though Ohio never passed its own law.

Why brake pads had copper in them in the first place

Copper wasn't filler. In a semi-metallic friction formula, copper fibers and powder raise the pad's thermal conductivity, which pulls heat away from the pad-rotor contact surface faster and helps resist brake fade on long descents or repeated hard stops. As the pad wears, those copper particles also help form the thin transfer layer on the rotor surface that semi-metallic pads rely on for a stable, predictable coefficient of friction and for keeping noise down. Manufacturers used it because, at the time, it was one of the most effective ingredients for getting high-temperature stopping power out of an affordable pad.

Why regulators went after copper specifically

Every time a pad wears, a small amount of friction material becomes dust, and some of that dust is copper that washes off roads and parking lots into storm drains. California's legislative analysis of SB 346 cited roughly 1.3 million pounds of copper entering the state's waterways every year from vehicle braking before the law took effect. That matters because copper is toxic to aquatic life at low concentrations: it damages the algae that forms the base of the food chain in streams and estuaries, and it is well documented to interfere with salmon's sense of smell, which they depend on to navigate back to spawning streams and to detect predators. The EPA has reported that urban runoff copper levels have dropped as much as 61% in areas affected by the brake pad phase-out, which is the real-world result the law was written to produce.

What replaced copper in modern pads

Pad makers didn't just pull copper out and leave a hole - they shifted to different friction chemistries, and the differences show up in how a pad feels and how it ages.

Most daily-driver replacement pads sold today, including ceramic brake pads, were reformulated around fibers like aramid, carbon and various metal oxides to replace the thermal and friction-layer role copper used to play, without the runoff problem.

How to tell what's actually in the pad you're buying

Every pad sold in the U.S. carries an edge code stamped into the backing plate, and compliant boxes are also marked to show they meet the current copper limit. The edge code itself is about friction coefficient, not copper content, so it won't tell you the copper percentage directly - for that, you're relying on the manufacturer's compliance marking and, where it's published, the brand's own material safety data. If you want to understand what those edge-code letters are actually telling you about a pad's friction behavior, see our guide to brake pad edge codes. Since 2025, any pad legally sold in the U.S. is already at or under the 0.5% copper threshold, so for a daily-driven car the practical choice is less about copper and more about which friction chemistry suits how you drive - a question our ceramic vs. semi-metallic comparison walks through in more detail.

What to check or replace when you put new pads on

A copper-free reformulation changed the pad, not the rest of the brake system, so the same service basics still apply. Inspect rotors for scoring, hard spots or thickness below the minimum stamped on the hub before reusing them with new pads - mismatched new pads and worn rotors are a common cause of noise and uneven wear. Replace worn hardware (shims, clips, anti-rattle springs) at the same time rather than reusing hardware that's already lost its spring tension, and lubricate caliper slide pins so the pad wears evenly on both sides. If dust has always been a complaint on your vehicle, a ceramic or NAO pad from our brake pad collection will generally run cleaner than a semi-metallic pad at the cost of slightly less bite when cold.

Frequently Asked Questions

Is it illegal to sell brake pads with copper in them now?

No - the law doesn't ban copper outright, it caps it. As of January 1, 2025, brake friction material sold in the U.S. must contain no more than 0.5% copper by weight, which most manufacturers meet with little to no copper at all rather than formulating right up to the limit.

Does this law apply outside California and Washington?

Functionally, yes. California and Washington passed the actual statutes, but a 2015 memorandum of understanding between the EPA, state regulators and major brake and vehicle manufacturers extended the same copper limits nationwide, so pads sold anywhere in the U.S. are built to the same standard.

Will copper-free pads stop as well as the old semi-metallic pads did?

For normal daily driving, yes. Modern ceramic and NAO formulas were specifically developed to replace copper's thermal and friction-layer role, and they perform well under typical commuting loads. Vehicles doing heavy towing or repeated hard braking still do better on a low-copper semi-metallic pad engineered for that duty, which stays within the legal copper cap.

How do I know if the pads I'm buying are compliant?

Compliant pads are marked on the box to show they meet the current copper and heavy-metal limits, and the manufacturer has third-party lab certification on file with the states' regulators. Any pad sold through a mainstream U.S. retailer today is already built to the 2025 limit.

Did removing copper change how brake dust looks or how often I need to clean my wheels?

It can reduce it. Ceramic and NAO pads generally produce lighter-colored, lower-volume dust than older semi-metallic formulas, so wheels tend to stay cleaner longer, though some dust is unavoidable with any friction material.

Sources

1. California Legislature - SB 346 bill analysis - the 5%/2021 and 0.5%/2025 copper thresholds, heavy-metal bans, certification requirement and exemptions
2. Washington State Department of Ecology - confirms Washington's Better Brakes Law phase-out of copper by 2025 and its exemption framework
3. U.S. EPA archived press release - the January 21, 2015 nationwide MOU, its signatories, the 1.3-million-pound copper figure and the 61% urban runoff reduction