ISO 14001 is a set of ground rules or criteria for an environmental management system that does not state requirements for environmental performance, but maps out a management system a business or organisation to follow.
ISO 14001 is a voluntary code that aims to assist companies in continually improving their environmental performance. There for the individual business that becomes certified for ISO 14001 can make as much or as little of their business come under their ISO 14001 management system.
A minimum standard for all businesses that do engage with ISO 14001 is that they are legally compliant in their jurisdiction