A few months ago, a client of mine who sells wireless speakers online got a scary letter from California’s Attorney General’s office: they were being fined $2,500 for violating Proposition 65 (Prop 65), a California law that requires businesses to warn consumers about exposure to harmful chemicals. The issue? Their speaker casings contained trace amounts of lead (0.004%), which is above Prop 65’s 0.001% threshold for consumer products. By the time they fixed the issue and paid the fine, they’d lost $5,000 in sales and had to pull their products from California retailers for six weeks.
If you sell audio products in California—either online (via Amazon, Shopify, etc.) or through brick-and-mortar retailers—Prop 65 isn’t a law you can ignore. California is the largest consumer audio market in the U.S., accounting for 18% of all audio product sales (2025 Statista data), and non-compliance can lead to fines of up to $2,500 per day for ongoing violations. For small and mid-sized audio brands, these fines can be devastating—not to mention the lost shelf space and damage to your brand reputation.
In this post, I’ll break down what Prop 65 means for audio products, identify the most common harmful chemicals to watch out for, and share how to make your products compliant (without breaking the bank). This isn’t just a compliance guide—it’s a way to protect your sales in California and build trust with consumers who care about product safety.
What Is Prop 65, and Why Does It Matter for Audio Products?
Proposition 65, officially known as the Safe Drinking Water and Toxic Enforcement Act of 1986, is a California law that requires businesses to provide clear warnings to consumers about products that contain chemicals known to cause cancer, birth defects, or other reproductive harm. The law applies to all products sold in California, including audio products like headphones, speakers, and earbuds.
The biggest misconception about Prop 65 is that it “bans” harmful chemicals—it doesn’t. Instead, it requires businesses to warn consumers about any chemical in a product that exceeds California’s safe exposure limits. For audio products, this means adding a clear warning label (either on the product, packaging, or online listing) if your product contains any of the 900+ chemicals on the Prop 65 list.
What makes Prop 65 tricky for audio brands is that the safe exposure limits are extremely low—far lower than federal limits. For example, the federal limit for lead in consumer products is 0.01% (100 ppm), while Prop 65’s limit is 0.001% (10 ppm). A small amount of a chemical that’s legal federally can still trigger a Prop 65 warning in California.
The Prop 65 Warning Requirements for Audio Products
If your audio product contains a chemical above Prop 65’s limits, you must provide a clear and reasonable warning to consumers. The warning can take three forms:
- On-Packaging Warning: A label on the product’s box (e.g., “WARNING: This product contains a chemical known to the State of California to cause cancer.”)
- In-Product Warning: A label on the product itself (e.g., a sticker on the speaker casing) for products where the packaging is discarded.
- Online Warning: A prominent warning on your product listing (Amazon, Shopify, etc.) for online sales.
The warning must be in English and Spanish (California’s two official languages) and use a font size of at least 12 points (for printed warnings) or 14 pixels (for online warnings). Vague warnings like “May contain harmful chemicals” are not sufficient—you must specifically name the chemical (e.g., “WARNING: This product contains lead, a chemical known to the State of California to cause cancer.”) if the chemical is on the Prop 65 list.
We helped the speaker brand client rewrite their Prop 65 warning to meet these requirements—they added a clear on-packaging warning in both English and Spanish, and their online listings included a prominent warning at the top of the product description. Within a month, they were back on California retailer shelves, and they haven’t had any further compliance issues.
The Most Common Prop 65 Violations for Audio Products
Audio products contain a variety of materials that can trigger Prop 65 warnings if not sourced carefully. Below is a breakdown of the most common chemicals found in audio products that violate Prop 65, where they’re typically found, and how to avoid them.
| Chemical | Prop 65 Safe Limit | Where It’s Found in Audio Products | Common Violation Scenario | How to Avoid Non-Compliance |
|---|---|---|---|---|
| Lead | 0.001% (10 ppm) | Speaker casings, solder, wiring, battery connectors | Using cheap plastic casings with recycled content that contains lead; using untested solder for driver wiring | Source casings from suppliers who provide Prop 65-compliant material certificates; use lead-free solder (Sn-Cu or Sn-Ag-Cu alloys) |
| Cadmium | 0.004% (40 ppm) | Battery casings, metal parts (e.g., headphone adjusters) | Using low-quality battery casings made with cadmium-plated metal; using untested metal parts for headphone hardware | Choose lithium-ion batteries with plastic casings; source metal parts from suppliers who test for cadmium |
| Phthalates (DEHP, DBP, BBP) | 0.1% (1,000 ppm) | Plastic ear tips, rubber gaskets, wiring insulation | Using flexible plastic ear tips that contain phthalates for softness; using rubber gaskets with phthalate-based plasticizers | Use phthalate-free plastic (TPU or silicone) for ear tips; choose EPDM rubber gaskets (phthalate-free) |
| Mercury | 0.001% (10 ppm) | Button batteries (rare in modern audio products) | Using old-style button batteries in small audio devices (e.g., kids’ headphones) | Use lithium-polymer batteries instead of button batteries; source batteries from Prop 65-compliant suppliers |
| Hexavalent Chromium | 0.0001% (1 ppm) | Metal plating (e.g., headphone hinges, speaker grilles) | Using chrome-plated metal parts that contain hexavalent chromium; using untested plating for decorative parts | Use stainless steel or aluminum parts instead of chrome plating; source plated parts from suppliers with Prop 65 certification |
We work with a network of material suppliers who specialize in Prop 65-compliant components for audio products. For the speaker brand client, we connected them with a plastic casing supplier who provided a Prop 65-compliant certificate for their casings (lead content: 0.0005%, well below the 0.001% limit). The supplier’s casings were priced competitively (a 5% increase over their previous supplier) and eliminated their lead violation entirely.
How to Make Your Audio Products Prop 65-Compliant (On a Budget)
The good news is that Prop 65 compliance doesn’t have to be expensive—especially for small and mid-sized audio brands. You don’t need to redesign your entire product; you just need to source compliant components and add the required warnings (if needed). Here’s how to do it step by step:
Step 1: Test Your Current Products for Prop 65 Chemicals
Before you make any changes, test your existing products to see if they contain chemicals above Prop 65’s limits. You can hire a third-party lab (we recommend labs accredited by the California Department of Public Health) to test for the most common chemicals (lead, cadmium, phthalates). Testing costs $300–$500 per product, which is far less than the $2,500 fine for non-compliance.
We helped a kids’ headphone brand test their products last year, and they found that their ear tips contained DEHP (a phthalate) at 0.15% (above the 0.1% limit). They switched to phthalate-free silicone ear tips (cost: $0.10 more per unit) and avoided a Prop 65 violation.
Step 2: Source Prop 65-Compliant Components
Once you know which chemicals to avoid, source components from suppliers who provide Prop 65 compliance certificates. These certificates prove that the component has been tested and meets Prop 65’s limits. Most reputable suppliers will provide these certificates for free—if a supplier refuses, walk away.
We maintain a list of Prop 65-compliant component suppliers for audio products, including driver manufacturers, plastic casers, and battery suppliers. For a wireless earbud brand, we connected them with a battery supplier who provided a Prop 65 certificate for their lithium-ion batteries (cadmium content: 0.0002%), and their products passed California’s testing with no issues.
Step 3: Add Clear Warnings (If Necessary)
If your product still contains a chemical above Prop 65’s limits (e.g., a small amount of lead in a metal part that’s unavoidable), add the required warning label. This is far better than skipping the warning and facing a fine—consumers in California are used to Prop 65 warnings and will still buy your product if the warning is clear.
We help our clients design compliant warning labels that meet California’s font and language requirements. For a portable speaker brand, we created a bilingual warning label that fit on their packaging without cluttering the design, and their sales in California actually increased by 3% (consumers appreciated the transparency).
Step 4: Update Your Online Listings for California Shoppers
If you sell audio products online, make sure your product listings include a Prop 65 warning for California shoppers. Amazon and Shopify both have built-in tools to add region-specific warnings—use these tools to target California customers only (warnings aren’t required for shoppers outside California).
We helped a headphone brand update their Amazon listings with a California-specific Prop 65 warning, and they saw no drop in sales—shoppers in California simply acknowledged the warning and continued to buy the product.
Final Thoughts: Prop 65 Compliance Is About Transparency
Prop 65 isn’t about scaring consumers—it’s about transparency. California shoppers value knowing what’s in the products they buy, and a clear Prop 65 warning (or better yet, a compliant product) builds trust in your brand. For small and mid-sized audio brands, compliance is a small investment that protects your sales in California and keeps your products on shelves.
We’ve helped dozens of audio brands navigate Prop 65 compliance, and the ones that embrace it as a way to build trust are the ones that thrive in the California market. Whether you’re a small online brand or a mid-sized retailer, take the time to test your products and source compliant components—you’ll be glad you did when you avoid that first fine.
