In order to improve the predictability of sprinkler response time for a confined ceiling, thermal properties of fusible sprinkler and environment of sprinklers below a confined ceiling during fire are discussed. A method of estimating the heat loss from a fusible link of the sprinkler fitting and the response of the link to external radiation is proposed. Measurements of temperature, velocity, radiation, and sprinkler response time below a ceiling are made in a 11.1 m × 8.1 m confined enclosure. The measured temperature and velocity are found to be close to previous theory for an unconfined ceiling if a correction for the existence of smoke layer is applied. Finally measured sprinkler response time is compared with calculation based on measured temperature, velocity and radiation history. The result shows the significance of radiation from the fire source in the determination of sprinkler response times.

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In practical fire fighting situations, there is a possibility that different foams will be applied to a tank fire in sequence or simultaneously by a fire brigade.
This report was to ascertain the compatibility of two different foams or a single foam when applied to gasoline fires simultaneously through two nozzles by plunging application or gentle surface application.
Comparative performance was judged by extinction time, fuel vapor sealability and burnback resistance of the foams.
When applied by plunging application, synthetic detergent foam greatly reduced the extinction time, fuel vapor sealability and burnback resistance compared to protein foam, fluoroprotein foam or fluorochemical foam (Light Water) used alone.
Protein foam was compatible with Light Water, when applied by plunging and gentle application.

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Some reactive materials, such as oxidizing materials, become less hazardous when they are shaped. In this report, we tried some methods to evaluate burning and explosion hazards of the shaped materials.
To evaluate the hazard of shaped materials requires bigger sample size than that of powdery materials. So we made some preliminary experiments for the mixture of the high strength calcium hypochlorite (HCH) tablets and the mixture of the standard materials to avoid occurrence of burning or explosion accidents. The results of the experiments showed that the mixture of the HCH tablets and a fuel for the detonation propagation test had sufficient stability and the mixture for the burning rate test had no ability to propagate a detonation. And referring to the results, the mixing ratios of the standard materials and the fuel for the tests were decided.
The detonation propagation test showed that the sample mixture had no ability to propagate a detonation, and the burning rate test showed that the sample mixture did not sustain a burning.

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