Carbon Footprint:

A carbon footprint is the sum of all greenhouse gas (GHG) emissions that a company emits into the atmosphere. Greenhouse gases are those that absorb and emit infrared radiation in the wavelength range emitted by Earth.

Working to reduce harm to the environment is a major component to sustainability. Companies that determine their overall carbon footprint quickly discover cost savings in many areas that were previously unnoticed.

In 2010 the EPA enacted a law requiring companies to report their greenhouse emissions under the Greenhouse Gas Reporting Program (GHGRP) for their facilities (stationary sources). Companies can also report their Carbon Footprint to the Carbon Disclosure Project to show transparency and build goodwill with their stakeholders.

Major Greenhouse Gases*

Greenhouse Gas Common Sources
Carbon Dioxide (CO2) Fossil-fuel combustion, land-use conversion, cement production
Fossil fuels, rice paddies, waste dumps
Nitrous Oxide
Fertilizer, industrial processes, combustion
Tropospheric Ozone
Fossil fuel combustion, industrial emissions, chemical solvents
Liquid coolants, foams
Sulfur Hexaflouride
Dielectric fluid
*Source: Center for Climate and Energy Solutions Website: C2ES Facts

EPA GHG Reporting Regulations*
*Subpart A - General Provision of Code

§98.1 Purpose and scope.

(a) This part establishes mandatory greenhouse gas (GHG) reporting requirements for owners and operators of certain facilities that directly emit GHG as well as for certain suppliers. For suppliers, the GHGs reported are the quantity that would be emitted from combustion or use of the products supplied.

(b) Owners and operators of facilities and suppliers that are subject to this part must follow the requirements of this subpart and all applicable subparts of this part. If a conflict exists between a provision in subpart A and any other applicable subpart, the requirements of the applicable subpart shall take precedence.

(c) For facilities required to report under onshore petroleum and natural gas production under subpart W of this part, the terms Owner and Operator used in subpart A have the same definition as Onshore petroleum and natural gas production owner or operator, as defined in §98.238 of this part.


First you must decide the organizational boundaries and the the operational boundaries described below in "Scope of what to measure". Then you need a data collection strategy. After all the data is gathered it must be converted into standard CO2e units. (Carbon Dioxide Equivalent Units.) See EPA Greenhouse Gas Equivalencies Calculator: GHG Equivalenccie

ISO 14064-1 "Greenhouse Gases" provides companies the specifications with guidance for quantifying and reporting greenhouse gas emissions and removals. (ISO-14064-1). There are many software solutions available and simple online carbon footprint calculators that offer a step by step process with relevant contributors outlined.

The Carbon Disclosure Project (CDP) a NGO provides guidance and recommendations.


Carbon neutrality, or having a net zero carbon footprint, refers to achieving net zero carbon emissions by balancing a measured amount of carbon released with an equivalent amount sequestered or offset, or buying enough carbon credits to make up the difference. It is used in the context of carbon dioxide releasing processes associated with transportation, energy production, and industrial processes such as production of carbon neutral fuel. Many companies have included becoming carbon neutral as part of their long term sustainability goal.


The Greenhouse Gas Protocol
Low Carbon Technology Partnerships initiative
Carbon Disclosure Project
ISO 14064-1 GHG Reporting Guidance
EPA-Greenhouse Gas Reporting Program (GHGRP)
EPA-Mandatory Greenhouse Gas Reporting Code
EPA-Toxics Release Inventory (TRI) Program
EPA- Office Carbon Footprint Tool
The Climate Registry GHG accounting tools
International Civil Aviation Organization (ICAO) Carbon Emissions Calculator
Buy Carbon Credits - terrapass
Buy Carbon Credits - 3 Degrees
What is Carbon offsetting?


The GHG Protocol Corporate Standard classifies a company’s GHG emissions into three ‘scopes’. Scope 1 emissions are direct emissions from owned or controlled sources. Scope 2 emissions are indirect emissions from the generation of purchased energy. Scope 3 emissions are all indirect emissions (not included in scope 2) that occur in the value chain of the reporting company, including both upstream and downstream emissions. Source: Greehouse Gas Protocol FAQ