Data collection is of prime importance in fire safety, for several reasons: assessing the effect of any regulation, providing probability and gravity data to fire risk analysis, and the selection of scenarios for examples in fire safety engineering. Statistical data collection of fires is nevertheless collected and analysed from local or national perspectives at the time of publication of this document, making any comparison difficult. A first step identified in the need for harmonization is the issue of terminology. This document defines terminology relating to fire statistical data, in order to supplement ISO 13943 for this specific field of application.