Does the steam or smoke from my boiler or chimney count as carbon?

The steam itself is not on the list. Water vapour is not on the Greenhouse Gas (GHG) Protocol's list of gases. What counts is the fuel you burn to make it, which is your Scope 1. Steam you buy from a neighbour counts as your Scope 2.

What is on the list

The Corporate Standard, the main GHG Protocol rulebook for company footprints, covers carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs) and sulphur hexafluoride (SF6). The GHG Protocol's list now has seven gases, those six plus nitrogen trifluoride (NF3), and the Securities and Exchange Board of India (SEBI) format for Business Responsibility and Sustainability Reporting (BRSR) lists the same seven.

My reading of those lists: water vapour is not on either list, so the steam you see is not a line in your footprint.

What does count

• The fuel burnt in your boiler, furnace or generator. The Corporate Standard puts emissions from combustion in owned or controlled boilers, furnaces and vehicles in Scope 1.
• You count it from the fuel bill, not from the look of the plume. The Corporate Standard counts from the fuel you burn, so the colour of the plume does not change the fuel-based figure.

Smoke, soot and other gases

The Corporate Standard says gases it does not cover, such as chlorofluorocarbons (CFCs) and nitrogen oxides (NOx), shall not be included in Scope 1 but may be reported separately. My reading: other things coming out of a chimney are a different question from your carbon count and are not in your Scope 1 total.

Steam you buy

If another company makes the steam and sells it to you, it is your Scope 2. The Corporate Standard uses the word electricity as shorthand for electricity, steam, and heating or cooling. SEBI's BRSR text says Scope 2 results from purchased or acquired electricity, heating, cooling and steam consumed by the entity. Ask the seller for its own emission figure per tonne of steam.

Example: a diesel-fired boiler, one month

• Fuel bought: 500 litres of diesel x 2.645 kilograms (kg) of CO2 per litre = 1,322.5 kg of CO2, about 1.32 tonnes.
• The steam produced does not add a second line. The fuel bill already carries the carbon.
• Small amounts of methane and nitrous oxide from the same burn are covered on the linked page.

Example quantity only.

What Senseible does here

Senseible reads fuel invoices and electricity bills into records, so the quantities behind each figure are on file. Senseible's standard check counts from what you bought, not from what leaves the chimney. Meters and sensors are custom, on request.

• Methane and nitrous oxide from burning diesel
• How many kg of CO2 does one tonne of steam produce?
• Common steam supplier in a chemical park: Scope 2
• Free calculators

Sources: GHG Protocol Corporate Accounting and Reporting Standard, revised edition (Introduction and Chapter 4, gases covered and scopes), SEBI Master Circular of 11 July 2023, Section IV-B and the BRSR format, IPCC 2006 Guidelines, Volume 2 Energy, Chapter 1 (Tables 1.2 to 1.4)

Last reviewed 2026-11-07. The Scope 1 and Scope 2 wording is from the GHG Protocol Corporate Standard and the SEBI July 2023 master circular. The GHG Protocol's own page now lists seven gases including NF3 (required gases amendment, February 2013); the six-gas list is the 2004 text. SEBI lists the same seven. The sentence that water vapour is not on either list is our reading of those lists, not a quote. The diesel factor is the IPCC-based figure Senseible uses.