## 1 Introduction  
In the last two decades, the size of spaces has considerably decreased, leading to a reduced area allocated per user, with constructions not aimed at space optimization becoming increasingly rare. In office spaces, this area has shrunk significantly, reaching values of 19.5 m\({}^{2}\) in the European Union and 16 m\({}^{2}\) in the United States [1], and sometimes even lower. This trend has resulted in a continuous increase in demand for office spaces, a phenomenon that is evident in cities such as Bucharest, where the demand has grown by approximately 75% from 2012 to the present [2]. In this context, the outbreak of a fire in an office becomes not only a plausible scenario but a major concern for building safety and occupant protection. Fires continue to represent the primary cause of emergency situations, with severe effects on both people and property. Although advances in fire safety have led to reduced risks across various types of buildings, new architectural configurations and modern interior design materials--especially plastics--have increased the danger by amplifying the emission of toxic gases (CO, CO\({}_{2}\)) and reducing visibility [3, 4, 5, 6, 7]. As a result, understanding fire dynamics remains a top priority for research. Heat Release Rate (HRR) is a central parameter in fire behavior analysis, reflecting combustion intensity, temperature evolution, toxic gas generation, and flame propagation. HRR has a key role in assessing thermal conditions within a fire-affected compartment and in calibrating advanced numerical models (CFDs). Without an accurate characterization of HRR, estimates related to fire safety, ventilation, or evacuation can become unreliable in real-life scenarios [8]. Without an accurate characterization of HRR, estimates related to fire safety, ventilation, or evacuation can become unreliable in real-life scenarios. In the specialized literature, the use of standardized temperature-time curves--such as ISO--developed under laboratory conditions, with simplified geometries and limited fuel quantities, is a common practice [9; 10; 11]. Although useful for material testing, these models fail to capture the complex behavior of real fires, particularly in office buildings that typically feature open layouts, modern furnishings, and a high load of synthetic combustibles [12; 13; 14]. Recent studies have experimented with determining the heat release rate (HRR) through mass loss methods, as referenced in [15; 16; 17; 18; 19; 20; 21; 22], typically focusing on simplified scenarios with small-scale fire sources and reduced thermal loads. Full-scale experimental studies, especially for office-type fires, are extremely rare or lacking entirely, creating a significant knowledge gap in terms of how real fires behave in such environments and how accurately simulation models can capture this behavior. This paper aims to close that gap by conducting a full-scale fire experiment in an office setting, generating rare and high-fidelity data used to calibrate and validate a Fire Dynamics Simulator (FDS) model. The originality of the research lies in combining robust experimental results with detailed numerical modeling to closely replicate temperature distributions and HRR evolution under real conditions. By doing so, the study not only advances the field with a rare and reproducible validation dataset but also proposes an integrated, interdisciplinary framework that overcomes the limitations of current standard-based approaches and enhances the practical reliability of fire simulations in modern administrative buildings. In this context, the current study aims to address an office fire through an experimental study to determine the real fire curve, using wood cribs as a fuel source, in a full-scale experimental stand.