Nickel is a heavy metal elements likely cause of allergy in human’s skin. Medical observation proves that long-term exposure to nickel-containing objects can cause skin allergies and even cancer. Excessive amount release of nickel in metal eyewear can result in harm to human health. International Organizations and the European standardization organization (CEN) have strict management measures on this. 
EU countries have strict rules and standards for metal eyewear. Metal eyewear won’t allow to sale to consumers with excessive nickel release amount. In June 1994, EU issued a 94/27/EC directive, providing standard for release amount of nickel. In July 1997, the EU released 3 harmonized standards, defines the method of a qualitative analysis of nickel amount of release. ISO/TS24348 method for detection of nickel release in 2007 of the officially promulgated, which expressly provides that: Metal eyewear with the wearer’s skin and prolonged exposure to nickel and alloy components of release amount shall less than 0.5μg/ｃ㎡/week.
To be issued by the ISO12312-1 of the sunglasses are a direct reference to the provisions and requirements: Sunglasses designer and manufacturer shall not endanger the health or safety of the wearer, and should minimize the risk of possible damage the wearer’s skin by the lens or frame material. 
Korea technical standards (KATS) published belongs to the proposed modifications to the safety and quality mark for industrial products, this proposal seeks to amend the safety and quality standard in sunglasses and optical fame, the release of nickel for sunglasses and optical frame to adjust to less than 0.5μg/ｃ㎡/week.
From the current status, Chinese eyewear products accounted for more than 70% of the world’s total eyewear production amount, and exports more than 60% to the international eyewear market. However many domestic manufacture of metal eyewear adopts low cost of nickel plating.
Since International Organizations (ISO) and the European standardization organization (CEN) have new stringent requirements of release amount of nickel, which brought a great impact on domestic eyewear industry, it becomes necessary for well understanding production method for the detection of nickel release.
As a professional metal eyewear manufacturer, we adhere to the ISO and European Organization for Standardization (CEN), we cooperate with quality electroplating factory and signed contracts and agreements related to the nickel release test. Each batch of metal eyewear should pass through the nickel release test.