# Uncertainty analysis of physical-based carbon accounting in cotton T-shirt manufacturing

## TL;DR

This paper analyzes the uncertainty in calculating carbon emissions for making a cotton T-shirt and finds that fabric production is the biggest source of emissions and uncertainty.

## Contribution

The study introduces a detailed uncertainty analysis of carbon accounting in cotton T-shirt manufacturing using a pedigree matrix approach.

## Key findings

- The cradle-to-gate carbon footprint of a cotton T-shirt is 1.37 kg CO₂e with ±13.81% uncertainty.
- Fabric production contributes over 60% of emissions and nearly 70% of uncertainty due to energy-intensive processes.
- Yarn spinning and sewing have smaller but notable impacts compared to fabric production.

## Abstract

The textile sector contributes significantly to global greenhouse gas emissions, yet product-level carbon accounting in this industry remains constrained by data gaps and methodological uncertainty. This study quantifies the uncertainty embedded in process-based carbon accounting for the cradle-to-gate production of a cotton T-shirt. We evaluated secondary activity data and emission factors using a pedigree matrix across five data quality indicators: precision, completeness, and temporal, geographical, and technological representativeness. The total cradle-to-gate carbon footprint was \documentclass[12pt]{minimal}
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\begin{document}$${1.37}\,\hbox {kg}\,\hbox {CO}_{2}\hbox {e}$$\end{document} per T-shirt, with an overall uncertainty of ±13.81 %. Fabric production was the largest source of emissions and uncertainty, contributing over 60 % of total emissions and nearly 70 % of total uncertainty, driven by energy-intensive processes such as weaving, dyeing, and sanforising. Yarn spinning was a secondary hotspot, while the sewing stage had comparatively minor impacts. The results show significant variation in data reliability across production stages and highlight the need for improved primary data, updated emission factors, and harmonised databases to strengthen the robustness and comparability of process-based carbon accounting in the textile sector.