Before you can start collecting information for your carbon footprint, you need to set your boundaries - what you will count and what you will exclude. The GHG Protocol is the basis for most national schemes, and offers help on this for both organisational and operational boundaries.

Setting the organisational boundary defines which parts of a group of companies are included - you may have a number of subsidiaries, some of which are wholly owned, and some partly owned, or there may be joint ventures, or franchises.

The operational boundary defines the depth to which you analyse your emissions: there are three boundary levels within the Protocol, referred to as 'Scopes'.

Scope 1

This measures emissions from your direct activities - equipment you own or control that is actually emitting GHGs. For a printer, this might be the emissions from a gas boiler, from vehicles you own, or from leaks of refrigerant gases used in air-conditioning units, some of which are very potent GHGs.

Scope 2

This accounts for the emissions from the production of purchased electricity - you are indirectly creating emissions here, by using the electricity.

Scope 3

Scope 3 looks beyond your direct operations and involves the work collecting information.  The emissions counted here are those that result from your activities, but are not from sources you own or control. Waste disposal comes into Scope 3, as incineration gives rise to CO2, amongst other gases, and landfill to methane. Business travel on public transport, staff travel to and from work - any transport that takes place as a direct result of your business activity, but using vehicles you don't own, falls into Scope 3. The emissions created in making the goods, materials and services you buy, so-called 'embodied emissions', are also counted here.

If reporting Scope 3 emissions you don't necessarily have to include all the elements - but you do have to be clear about what you do include or exclude and why, and say where estimates are used. The Protocol, or where relevant, Government or scheme guidance documents, include advice on this.