10.20 Jul 7, 2026
ISO
ISO/TC 204
International Standard
This specification addresses the limitations of conventional estimation methodologies that rely on fuel-based data or aggregated annual vehicle mileage statistics. Existing approaches do not adequately reflect actual traffic conditions, and the time lag inherent in the inventory development process makes it difficult to determine, in a timely manner, whether greenhouse gas (GHG) reduction targets have been achieved.
To overcome these limitations, this specification is intended to provide improved accuracy and timeliness in the estimation of greenhouse gas emissions from the road transport sector by utilizing activity data collected from nomadic devices and traffic information data collected from Intelligent Transport Systems (ITS) detection devices.
ISO 23795-4 specifies a methodology for estimating greenhouse gas emissions from the road transport sector through the calculation of Vehicle Kilometres Travelled (VKT). The methodology utilizes data collected from nomadic devices, including density, speed, traffic volume, sample volume, and location information, together with measured values obtained from traffic detection devices, and applies expansion techniques to derive population-level traffic activity data.
This specification defines a VKT estimation method based on measured and estimated data for individual road sections. It also specifies a VKT calculation method, in accordance with the Tier 3 (T3) approach, in which the minimum unit of analysis is defined as the link between intersections, and VKT is derived using point-based average traffic volume by vehicle type and fuel type together with section length.
PROJECT
ISO/NP 23795-4
10.20
New project ballot initiated
Jul 7, 2026