The limiting oxygen index is the minimum concentration of oxygen, expressed as a percentage, that will support the combustion of a polymer. It is measured by passing a mixture of oxygen and nitrogen over a burning specimen, and reducing the oxygen level until a critical level is reached.
Here are some examples of safety standards and regulations related to PVC flammability:
1. Underwriters Laboratories (UL): UL is an independent safety certification organization that establishes standards for various products, including PVC materials. UL 94 is a widely recognized standard for testing the flammability of plastic materials, including PVC. It classifies materials into different flame ratings, such as V-0, V-1, V-2, HB, and others, based on their performance during specific fire tests.
2. International Electrotechnical Commission (IEC): IEC is an international organization that develops standards for electrical and electronic equipment. IEC 60695 is a series of standards that define test methods for evaluating the fire hazard of electrical components and materials, including PVC. These standards provide guidance on test procedures, criteria, and classifications related to flammability.
3. National Fire Protection Association (NFPA): NFPA develops and publishes fire protection and life safety standards. NFPA 130 is a standard specifically focused on fixed guideway transit and passenger rail systems. It includes requirements for materials used in rail cars, including PVC, to ensure their fire performance and minimize the risk of fire spread and smoke production.
4. European Union (EU) Directives: The EU has regulations in place to ensure the safety of products within its member states. The Construction Products Regulation (CPR) provides guidelines for the fire performance of construction products, which may include PVC materials used in building and construction applications. The regulation establishes harmonized standards, such as EN 13501, which classifies the fire performance of construction products.
5. American Society for Testing and Materials (ASTM): ASTM develops voluntary standards for various industries, including plastics and construction materials. ASTM E84 is a standard test method for assessing the surface burning characteristics of building materials, including PVC. It measures parameters like flame spread and smoke development during a specific fire test.
These are just a few examples of safety standards and regulations related to PVC flammability. It's important to consult the specific standards and regulations applicable to your region and industry for accurate and up-to-date information.