Recycling ensures hazardous materials are reused and not simply stored with the potential to cause problems in years to come. Batteries may contain caustic or acidic liquids, and toxic or hazardous metals such as mercury, cadmium, nickel and lead. Fluorescent lamps and High Intensity Discharge lamps contain mercury. Mercury is released into the air upon breaking and mercury also enters the environment through leaching at garbage dumps. ISO 14000 is a set of generic standards being developed by the International Organization for Standardization (ISO) which provides any company, regardless of size or type, with a structure for managing environmental impacts. The documents cover a range of environmental disciplines, including environmental management systems, auditing, environmental performance evaluation, labelling, life-cycle assessment, and environmental aspects in product standards. The standards themselves do not replace environmental performance goals as stated in Canadian federal and provincial regulations. Rather, they encourage companies to set about an international reference framework for achieving continuous environmental improvement. What standards have been published so far? The first two standards to have been published are ISO 14001, Environmental management systems - Specification with guidance for use, and ISO 14004, Environmental management systems - General guidelines on principles, systems and supporting techniques. These two documents are the pillars of the ISO 14000 series since they specify the requirements against which a company's environmental management system (EMS) is to be judged.