An instrumented mannequin has been constructed for testing the thermal protective qualities of garments when subjected to short duration flash fires. To measure the rate of heat transfer to the mannequin surface 110 skin simulant sensors are used. The flash fires are produced with propane diffusion flames. A computer controlled data acquisition system is used to run the experiment, record and store the data, calculate the extent and nature of skin damage and display the results. The sampling rate of the system is 800 Hz. The heat fluxes used in the study were varied from 67 kW/m2 to 84 kW/m2 (1.6 cal/cm2· s to 2 cal/cm2· s), while burn durations were limited to 3 and 4 seconds. Six different fibre/fire retardant/fabric weight combinations were tested. The results show that increasing the fabric weight for a particular fibre reduces the extent of skin burning. However some materials are more effective than others so that a general correlation of this form does not hold. Increasing the heat flux level and duration increased the predicted amount of skin burning with all the garments tested. There was a good correlation with TPP results at the low heat fluxes and durations, but not at the high values for each.
A study of bench top tests for thermal protective fabrics was undertaken to answer questions about the interpretation of data from these tests, and to evaluate suggested modifications to existing tests. Fixed duration tests using either skin simulant or copper disk heat flux sensors may be a useful alternative to existing bench top tests. However, more work is required before fixed duration tests can be implemented. While predictions of times to third degree burns for bench top test require the use of the Henriques' burn integral, the Stoll second degree burn criterion was found to predict times to second degree burns reasonably close to predictions made using Henriques' burn integral for many bench top test exposures. It was also found that the heat fluxes used in bench top tests may not be indicative of those in actual flash fires. Current tests which utilize a planar geometry were also found to adequately represent the heat transfer in the more complex geometry of the human body during these exposures.
There exist a number of national standards and a draft international standard for the fan pressurization method for measuring air leakage. Although the standardized methods in principle are the same, the way of interpreting and presenting the results is different. In previous studies, houses that have a relatively large leakage area at a low pressure difference (4 to 10 Pa) still can seem comparatively airtight at a high pressure difference (50 Pa). This fact is a consequence of differences in the flow exponent in the power-law equation, which is the normal equation used to fit to the data points, and can be a source of error when trying to compare the relative airtightness of houses. Extrapolating results from high pressure differences to low pressures, which are out of the measured range, can thus result in substantial errors. Air leakage testing of windows normally starts at 50 Pa, which should be accounted for when trying to use these results as inputs in network air infiltration models. Measurement results on low pressure air leakage are discussed in the paper and compared with high pressure air leakage. Pressurization test data from 105 tests in one house at the Alberta Home Heating Research Facility are used for the study. The tests were made automatically over a seven-month period in low wind conditions. A wide range of pressure differences were tested and the results cover the test specifications for most standards. In addition to comparing standards, these tests were used to measure seasonal effects on air leakage in a wood-frame house with a plastic film air/vapor barrier. The results show some significant differences between the standards, and also a variation with month of test, indicating a seasonal variation in air leakage.
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