The relative increase in disposal costs and regulatory requirements (an overall reduction in landfilling by 2025, and sorting at source of bio-waste) allow composting activities to continue to grow in France. This development is highly beneficial from an environmental standpoint, but it is accompanied by a significant increase in accidents in these activities. This document focuses on fires, the dominant hazardous phenomenon. The aim is to identify the vulnerabilities of these activities and propose measures to prevent and protect against accidents. A quick update is also given on intervention strategies and the consequences of accidents. The comments are illustrated by references to the events listed in the ARIA database.