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Interest in water mist fire suppression has increased within the fire protection industry due to its ability to control the spread and development of fire without using environmentally damaging agents. Water mist fire suppression has been used for many years in various applications such as machinery spaces, combustion turbine enclosures, and onboard passenger sea vessels. Now there is a demand to use this firefighting method to protect other fire risks such as cooking areas, commercial buildings, residential buildings, electrical equipment, road tunnels, bushfire (wildland fire) protection, and nuclear power generation facilities. To support this industry demand, this review covers the fundamentals of water mist, its suppression mechanisms, areas of application, existing research and development, and the codes and standards related to design. This comprehensive review provides a clear history of water mist suppression. It is able to identify the issues and challenges related to the technology to help pave the way for future research and development that will improve these systems to a level so that they are suitable for these new applications and meet the industry demand for nontoxic fire suppression systems. [ABSTRACT FROM AUTHOR]

Fire safety is a changing science for which the dominant parameters that affect fire suppression are still not well defined. The aim of this work is to show that sensitivity analysis techniques can speed up and improve the design process of fire suppression experiments by water mists. The important parameters that play a role in the performance of water mists were confirmed using the CFD code FDS. Various sensitivity analysis methods based on the factorial design and variance decomposition are used with four input parameters (flow rate, spray cone angle, discharge duration and droplet diameter). In our case, results highlight the importance of the discharge duration for the performance of water mists in a confined environment and a strong non-linear effect of the spray cone angle on temperature when variance decomposition methods are used. Further works will be conducted in order to confirm that sensitivity analysis can be used for application in fire suppression by water mist. [ABSTRACT FROM AUTHOR]

In this article, a collective database from validated numerical simulation has been established to study the suppression effects of water-based suppression systems under a single-compartment fire scenario at various suppression configurations and fire locations. Five fuel locations along the axis between the centre and corner of the room were configurated to dynamically analyse how the horizontal distance between the nozzle and fuel pan affects the heat release rate (HRR), temperature cooling phenomena at different heights and also the velocity profile. Throughout the fuel pan relocations, the water-mist system has achieved an average suppression time of 25 s for all the locations, it was found that the water mist system can effectively control the fire under 200 °C that is distanced over 2 m spanwise displacement from the nozzle against the fire, while the sprinkler has exhibited an excellent fuel surface cooling effect due to large momentum and heat capacity within the coverage area with an average suppression time of 50 s. The results of this study have further explored the spray coverage and droplet penetrability of different suppression systems at different locations corresponding to the fire source, and the quantitative assessment of fuel locations could also contribute to the future development of performance-based fire safety designs. [ABSTRACT FROM AUTHOR]

It is commonly assumed in fire modelling that suppression systems can control the heat release rate of a fire. However, many performance-based assumptions are derived from experimental data for sprinklers, and uncertainty remains for their application to water mist systems. In the UK, residential water mist systems are usually tested to the BS 8458:2015 standard, but the heat release rate in these tests is not quantified and focus is instead placed on thermocouple temperatures. This paper details a series of fire tests to the BS 8458:2015 standard for an electronically controlled water mist system. The paper also includes B-RISK zone modelling of these tests to estimate the suppression performance of the system, comparing model outputs to thermocouple test data. Three traditional suppression assumptions, historically derived from experimental data for sprinklers, have been adopted in the zone modelling to examine whether their application following system activation can be extended to the tested water mist system. The work indicates that applying these suppression assumptions remains reasonable in the context of the performance of the tested water mist system, noting the constraints of the test methods in representing a limited number of fire scenarios. [ABSTRACT FROM AUTHOR]