Watch strap certification report process in California Proposition 65
Date：2026-01-04 10:21:53 Classification
：【question】 Visits：
California Proposition 65 compliant watch straps, as accessories that come into direct contact with the skin, are indeed a high-risk area for Proposition 65 lawsuits, especially due to the risk of hazardous substance migration from materials such as leather, metal, and silicone. Understanding the process in advance can save you a lot of trouble. This document outlines the complete process for obtaining a California Proposition 65 certification report for watch straps (with specific material requirements).
I. Core Testing Items and Limits (Watch Strap-Specific Requirements)
| Material Type | Required Substances | Limit Requirements
| Metal Watch Straps | Lead (Total Lead) | ≤100ppm (Substrate) / ≤90ppm (Coating)
| Leather Watch Straps | Cadmium | ≤300ppm
| Silicone/Rubber Watch Straps | Phthalate (DEHP/DBP/BBP, etc. 6P) | ≤1000ppm each
| Nylon/Fabric Watch Straps | Lead (Surface Coating) | ≤90ppm
II. 5-Step Processing Procedure (Including Special Documents for Watch Straps)
1. Required Documents:
Product Information:
Material List (e.g., 316L stainless steel buckle, calfskin strap, liquid silicone strap)
Process Description (e.g., electroplating thickness ≥ 3μm, leather tanning process type)
Accessory List (including adhesive type, such as food-grade silicone)
Sample Requirements:
3 complete straps (including buckle, stitching, coating, and all other components)
If the strap contains multiple materials (e.g., metal + leather combination), samples must be submitted separately.
2. Key Points for Laboratory Selection
Qualification Verification: (e.g., Dezewei Testing CNAS Registration Number: L8083)
Strap Testing Experience: Prioritize institutions that have processed ≥500 batches of watch accessories.
Report Requirements: Must indicate "Tested according to California Proposition 65, Section 25249.6"
3. Testing Cycle and Costs
| Material Combination | Testing Cycle | Cost Range
| Single Material (e.g., all-steel) | 5 working days | ¥1000-1800/model
| Mixed Materials (Leather + Metal) | 7 Business Days | ¥1500-2500/model
4. Key Testing Steps
Metal Components:
Lead Plating Test (rapid screening using XRF; positive results require ICP-MS quantification)
Cadmium Leaching of Stainless Steel Buckles (immersion in 4% acetic acid for 24 hours)
Leather Components:
Hexavalent Chromium Detection (ISO 17075:2007, limit ≤3ppm)
Formaldehyde Emission (EN ISO 14184-1:2011, limit ≤75ppm)
5. Reports and Warning Labels
Report Core Elements:
Must include material breakdown test results (e.g., "Lead content in stainless steel buckle 85ppm"), test method standard number, and laboratory accreditation stamp.
Warning Label Specifications:
If lead content >100ppm, the packaging must state: "WARNING: This product contains chemicals known to the State of California to cause cancer and birth defects or other reproductive..." Harm. (Font height ≥ 6pt)
III. Common Failure Cases and Solutions for Watch Straps
| Reasons for Failure | Technical Analysis | Corrective Measures
| Excessive Lead Coating in Stainless Steel Buckles | Incomplete Degreasing of Substrate Before Electroplating Lead Residue | Switch to Environmentally Friendly Electroplating Process (Lead-Free Anodizing)
| Excessive DEHP in Silicone Watch Straps | Use Recycled Silicone Raw Materials | Purchase Food-Grade Silicone (e.g., Dow Corning 748)
| Excessive Cadmium Migration in Leather Watch Straps | Use of Cadmium-Containing Dyes in Tanning Process | Replace Vegetable Tanning Agents, Prohibit Chromium Salt Tanning.
Shen Gongwang Security: 44030602006947