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Results showed that using the NIST/JET ceiling jet algorithm gave a closer prediction of the sprinkler response time in a small room than Alpert's correlation. This was expected, since the former includes the effect of a hot upper layer while the latter applies to unconfined ceilings. The experiments available for comparison had been conducted inside an enclosure with a developing hot upper layer. The findings also signified that changing the sprinkler operational parameters can change the predicted sprinkler activation time significantly.

This article considers the predictive capabilities of Fire Dynamics Simulator for sprinkler actuation time when benchmarked against data from a series of 22 enclosure experiments. Sensitivity analyses have been undertaken for grid size, conductivity factor, radiative fraction and enclosure leakage areas. 'Goodness of fit' calculations indicate that Fire Dynamics Simulator is able to provide an average prediction of sprinkler actuation time within a Euclidean relative difference of 0.18. Comparisons to results determined in previous studies, using different modelling methods and Fire Dynamics Simulator versions, have also been made. The sensitivity analyses and comparisons indicate the importance of the decisions made by the modeller in representing fire scenarios, even when modelling 'simple' experiments where data for inputs such as the heat release rate, geometry and sprinkler characteristics are available. The comparisons therefore indicate that with the reduced degrees of freedom compared to other modelling studies, there is still potential for a range of assumptions and simulation results.

This paper describes an evaluation of the performance of a fast response residential sprinkler system in a simulated apartment in the event of a fire caused by a burning television set. The evaluation was conducted in an 8m × 4m × 2.4m high gypsum plasterboard lined compartment. A 1.2 m 2 lobby was used to represent an adjoining room and a standard hollow core door connected the two spaces. The compartment was fitted with two pendent mounted fast response residential sprinkler heads, and the television sets were located in one corner of the compartment. A series of 21 tests was conducted using a tea light candle against the outside of the television casing as the ignition source. Gas analysis for CO, CO 2 , O 2 was carried out along with measurements of visual obscuration, compartment temperature and mass loss of the fuel. Tenability conditions within the compartment were determined using Fractional Effective Dose calculations.The results showed that the sprinkler system did not respond well to the television fires. Conditions within the compartment approached or exceeded tenable limits on a number of occasions. In some instances the television set burned out completely without activating the sprinkler system.

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