Overview

Amazon sellers listing certain product categories in California must comply with the California Air Resources Board (CARB) regulations. These rules target products that can affect air quality — including aftermarket auto parts, catalytic converters, air cleaners, small gas-powered engines, portable gas containers, and composite wood products. Understanding these requirements is essential for sellers who want to avoid listing removals and maintain compliance when selling into the California market.

Key Points / What Sellers Need to Know

• CARB applies to specific product types — Aftermarket auto parts, catalytic converters, indoor air cleaners, small gas-powered engines, portable gas containers, and products containing regulated composite wood all fall under CARB oversight.
• Executive Order (EO) numbers are required — Many regulated products must be registered with CARB and carry a valid EO number to be sold in California through Amazon.
• Composite wood products have separate standards — Items containing hardwood plywood, medium-density fiberboard (MDF), thin MDF, or particleboard must meet CARB formaldehyde emissions standards and carry proper labeling.
• Non-compliant listings will be prohibited — Amazon will block sales of products that lack valid CARB registration, have had their EO number rescinded, or fail to meet formaldehyde emissions or labeling requirements.
• Sellers bear responsibility for compliance — It is the seller's obligation to determine whether their products are subject to CARB regulations before listing them on Amazon.

Which Products Are Allowed and Prohibited

Amazon permits the sale of aftermarket auto parts, catalytic converters, indoor air cleaners, small gas-powered engines, and portable gas containers in California only if those products have been registered with CARB and hold a valid Executive Order number. Composite wood products — including those containing hardwood plywood, MDF, or particleboard — are allowed only when they comply with CARB formaldehyde emissions standards and carry the required labels.

Conversely, Amazon prohibits the sale of any of these regulated products if they lack CARB registration, do not have a valid EO number, or if the EO number has been rescinded or withdrawn. Composite wood products that fail to meet emissions standards or are missing required labeling are also blocked from sale in California.