ISO issued a new global criterion July 7, 2008 for selecting methods and processes for recycling and reusing plastics that includes warning notes about the hazards of contaminants and advises against manually sorting plastic wastes. The standard, ISO 15270:2008, Plastics: Guidelines for the Recovery and Recycling of Plastics Waste, was developed to promote sustainable global infrastructure and markets for plastics recovery and recycling. ISO is a network of the national standards institutes of some 157 countries, with a Geneva-based secretariat that coordinates the system. The standards it develops are voluntary, although they can be implemented by its member organizations.