The International Organization for Standardization (ISO) and Greenhouse Gas (GHG) Protocol plan to “harmonize” their frameworks for emissions accounting and reporting, a move greeted with enthusiasm by professionals responsible for voluntary corporate disclosure.

The strategic partnership disclosed Sept. 9 by the two well-known international standards organizations seeks to unify the approaches used in ISO’s 1406X series of standards for managing greenhouse gas emissions inventories and product carbon footprints with GHG Protocol’s rules for how companies prepare statements for annual ESG and environmental reports. 

GHG Protocol’s guidelines are used by 97 percent of all companies that report. ISO, which represents 170 international standards bodies, has more than 25,000 standards, including around 600 processes related to energy, materials reuse and areas core to corporate climate action. 

The net effect of the new relationship will be to standardize how certain categories are defined across the frameworks for easier comparison. The partnership doesn’t apply to existing standards. New guidelines will eventually replace them.

“Investors need consistent, reliable data to deploy capital effectively in the transition to a low-carbon economy,” said Clara Barby, senior partner at investment firm Just Climate. “Together, ISO and GHG Protocol can provide coherent protocols as the basis for disclosure regions globally, offering the credibility and simplicity the market needs.” 

Deeper relationship

The two organizations have already been collaborating. ISO’s forthcoming net-zero standard, anticipated in late 2025, uses GHG Protocol’s definitions for its reference materials about how to consider emissions for Scope 1 (operational), Scope 2 (energy-related) and Scope 3 (upstream and downstream impacts). ISO and GHG Protocol are also aligning how they consider claims about carbon neutrality. 

Existing technical work at each organization will continue — both ISO and GHG Protocol are preparing big standards overhauls in 2025 — but governance teams are being asked to consider the harmonization process during that work, according to an ISO spokesperson.

No timeline was given for the work, but sustainability consultant Andrew Griffiths, who is involved with the ISO net-zero standard working group as co-founder of the Carbon Accounting Alliance, sugg