This paper presents experimental research findings for those involved in the early phase of fire in office buildings. Class A model fires with a reaction area from 5 cm2 to 300 cm2 were chosen for investigation. To mock up a fire, the following combustible materials typical of offices were used: wood pieces, heat-insulated linoleum, paper and cardboard. The main characteristics of a model fire were recorded: temperature in the combustion zone, heat release, time of complete burnout and concentration of flue gas components. Typical trends and histograms of changes of these characteristics over time were presented; stages of ignition, flame combustion and smoldering were illustrated. The key characteristics of fire detector activation at different stages of model fire combustion were analyzed. Dead bands and operation conditions of a group of detectors (smoke, heat, optical, flame), their response time and errors were identified. It has been established that the most effective detectors are flame and smoke detectors. Specific operational aspects of detectors were established when recording the ignition of different types of model fires. The viability of combining at least two detectors to record fire behavior was established. Recommendations were made on using the obtained findings when optimizing the systems for detecting and recording the start of a compartment fire.

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This paper presents experimental research findings on the gas composition of pyrolysis and combustion products of typical forest fuels (leaves, needles, twigs, a mixture of these, and timber). These experiments were performed for the combustion and application of a fire extinguishing agent to a pyrolyzing material. Water, a bischofite solution, a bentonite slurry, and a foaming agent solution were utilized. Two gas analysis systems were used, as follows: an industrial one based on CO2, CO, H2, CH4, and O2 sensors and a scientific one (a gas analyzer with H2, CH4, H2S, SO2, CO, and CO2 sensors). Fires were extinguished by using two common techniques, as follows: continuous liquid supply and cycling spraying. The comparative efficiency of applying a group of fire extinguishing agents to forest fires was estimated, taking account of liquid consumption, suppression time, and environmental pollution. A method was proposed for calculating the relative efficiency factors of fire extinguishing agents when containing and suppressing forest fires, allowing for the consumed time, resources, and anthropogenic emissions.

This paper presents experimental research findings regarding the characteristics of fire safety equipment activation before and after a water-based fire suppression system is triggered. A group of typical indoor combustible materials (wood, linoleum, cardboard, paper) were used to construct Class A model fires in the experiments. The three most frequent fire causes were reproduced: the careless handling of fire (open flame), the unsafe operation of heating equipment and electrical short circuits. To identify the fire behavior, an automated system including fire (heat, smoke, flame) detectors, contact and non-contact temperature measurement instruments, a gas analysis system and video recording equipment was employed. Following the experiments, the most efficient (in terms of detection speed and reliability) combinations of technical equipment that are necessary and sufficient to identify all the combustion stages of substances and materials were determined. The efficient consumption of a fire-extinguishing agent was found to be possible when fire development stages were controlled. Guidelines on creating automated fire prevention systems in buildings were provided. These have the potential to significantly speed up compartment fire suppression.