Typically, we suggest you start at Bronze level and work your way up as you gain knowledge of how to implement your EMS effectively across your organisation. However, the level which a business starts depends on what actions they have already undertaken and what can be achieved within the year. If you feel your business is already doing a lot of environmental action, and you only need to pull the work together into a system, you may wish to start at either Silver or Green. To be compliant at Silver and Green level you will have to have at least 12 months of baseline data, and a further 12 months of data for each resource to calculate the organisations percentage improvement.