Guidance

Calculate the carbon dioxide equivalent quantity of an F gas

Find out how to express the mass of a fluorinated greenhouse gas (F gas) in terms of carbon dioxide equivalent to comply with regulations on F gases.

• From: Environment Agency and Department for Environment, Food & Rural Affairs
• Published: 31 December 2014
• Last updated: 16 January 2024 — See all updates

Carbon dioxide (CO2) equivalent is a measure of how much a gas contributes to global warming, relative to carbon dioxide.

To calculate the carbon dioxide equivalent of a quantity of fluorinated greenhouse gas (F gas), multiply the mass of the gas (in metric tonnes) by the gas’s global warming potential (GWP).

Product labels on equipment will usually show the mass of F gas in kilograms. To convert kilograms to metric tonnes, divide by 1,000.

Find out the global warming potentials for F gases.

Example calculation

As an example, you may need to work out the CO2 equivalent for 10kg of hydrofluorocarbon (HFC) 404a. To calculate the tonnes of CO2 equivalent:

1. Divide the mass of the F gas in kilograms by 1,000 to calculate metric tonnes: 10kg ÷ 1,000 = 0.01 tonnes.
2. Multiply the mass (in metric tonnes) of F gas by the GWP of the F gas: 0.01 tonnes × 3,922 GWP = 39.2 tonnes CO2 equivalent.

When to use CO2 equivalent

You should calculate the CO2 equivalent when you:

• produce or import F gas and equipment into Great Britain
• check if services bans apply to your F gas equipment
• check your equipment for leaks
• record and report F gas and equipment pre-charged with F gas

Published 31 December 2014
Last updated 16 January 2024 + show all updates

1. 16 January 2024

   Added guidance on when you may need to calculate the carbon dioxide equivalent quantity of an F gas.

2. 20 February 2023

   Added 'metric' to metric tonnes for clarification. Added further detail to the column headers in the Table of CO2 equivalent thresholds for common F gases.

3. 31 December 2014

   First published.