ISO 19694-3:2023

Overview

ISO 19694-3:2023 provides a harmonized methodology for calculating greenhouse gas (GHG) emissions specifically for the cement industry. It establishes consistent rules for quantifying and reporting direct and selected indirect GHG sources at multiple reporting bases (plant, company by country/region, or international group). The standard supports reliable GHG inventories used for corporate reporting, regulatory compliance, carbon accounting and emissions reduction initiatives.

Key topics and technical requirements

• Scope of emissions covered: Direct GHGs from processes owned or controlled by the organization (e.g., calcination of carbonates, combustion in kilns and non-kiln equipment, on-site power generation, wastewater carbon), plus selected indirect emissions (purchased electricity and purchased clinker). Other indirect sources are excluded where specified.
• Measurement and calculation methods: Options include stack emission measurements (including continuous stack emission monitoring) and mass-balance approaches for key streams such as clinker and fuel.
• CO2 from calcination and fuels: Detailed guidance on determining CO2 released by raw material calcination and fuel combustion, with multiple input/output methods and reporting options for clinker-based factors.
• Gross vs. net emissions: Definitions and procedures for reporting gross emissions and accounting for reductions (e.g., waste heat utilization) or biogenic carbon content in fuels.
• Inventory boundaries: Clear rules for reporting boundaries (site, organizational), operational control and ownership criteria, and handling of internal transfers of clinker, cement and mineral components (MIC).
• Uncertainty and verification: Requirements and guidance for uncertainty assessment of activity data, fuel/material parameter analysis, continuous measurements, and overall inventory uncertainty; includes verification considerations.
• Reporting and indicators: Guidance on reporting periods, corporate environmental reporting, performance indicators and denominators appropriate to cement production.

Practical applications and users

ISO 19694-3:2023 is intended for:

• Cement plant environmental managers and sustainability teams
• Corporate GHG accountants preparing company-level inventories
• Third‑party verifiers, auditors and consultants performing GHG validation
• Regulators and policymakers setting sectoral reporting or compliance frameworks
• Investors and customers seeking comparable emissions data for benchmarking

Typical uses include regulatory compliance, corporate sustainability reporting, emissions trading preparation, identifying reduction opportunities (fuel switching, clinker substitution, waste heat recovery) and improving transparency in carbon accounting.

Related standards

• ISO 14064-1:2018 - Provides general principles for organizational GHG inventories and is explicitly referenced by ISO 19694-3.
• Other parts of the ISO 19694 series (see ISO website) address similar methodologies for other energy‑intensive industries.

Keywords: ISO 19694-3:2023, cement industry, greenhouse gas emissions, GHG inventory, calcination, clinker, kiln fuels, mass balance, stack emission measurements, ISO 14064-1.