摘要 :
The requirements for improved thermal protection garments for divers and a design philosophy for their development is discussed. An improved passive thermal protection garment for Navy divers has been shown to be thermally adequat...
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The requirements for improved thermal protection garments for divers and a design philosophy for their development is discussed. An improved passive thermal protection garment for Navy divers has been shown to be thermally adequate in 4.4 degrees C (40 degrees F) water. Design investigations and thermal evaluations leading up to the final suit configuration are summarized. (Author)
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摘要 :
Fire fighters' protective clothing provides a limited amount of thermal protection from environmental exposures produced by fires. This level of thermal protection varies with the design, materials, construction, and fit of the pr...
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Fire fighters' protective clothing provides a limited amount of thermal protection from environmental exposures produced by fires. This level of thermal protection varies with the design, materials, construction, and fit of the protective garments. Limits of thermal protection may be analyzed using the thermophysical properties of garment materials. However, little information is currently available for analyzing and predicting protective garment thermal performance. To address this need, a research effort was begun to measure the thermal properties of fire fighters' protective clothing materials. This report presents thermal conductivity data for ten materials used in fabricating fire fighters' protective clothing. These materials included: (a) outer shell fabrics, (b) moisture barriers, and (c) thermal liner battings. The thermal conductivity data for each material was obtained twice. Once when the material was new and once after the material had undergone a conditioning process of five washings and dryings by a contract cleaner that specializes in cleaning, decontaminating and repair of fire fighters' protective clothing. The thermal conductivity of individual protective clothing materials was measured using the test procedure specified in ASTM C 518 Standard Test Method for Steady-State Thermal Transmission Properties by Means of Heat Flow Meter Apparatus. Measurements producing estimates of thermal conductivity for a single layer of materials were carried out at mean test temperatures of 20C (68F), 48C (118F), 55C (131F), and 72C (162F). No visible physical changes were observed with any of the materials tested at these temperatures. For unconditioned materials, the thermal conductivity estimates ranged from 0.034 W/m K to 0.093 W/m K. For the conditioned materials the thermal conductivity estimates ranged from 0.033 W/m K to 0.089 W/m K. Thermal conductivity values increased for all materials as mean test temperatures were increased.
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摘要 :
A series of measurements has been carried out to quantify the thermal properties of materials used to fabricate fire fighters thermal protective clothing. The thermal property measurements chosen have direct application for use in...
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A series of measurements has been carried out to quantify the thermal properties of materials used to fabricate fire fighters thermal protective clothing. The thermal property measurements chosen have direct application for use in heat transfer model computations that may be used to predict the thermal performance of fire fighters protective clothing. The thermal properties are: thermal conductivity, specific heat, and the thermo-optical properties of absorptivity, reflectivity, and transmissivity. In addition, the physical property of density was also measured. Since thermal properties varywith ambient temperature conditions, thermal conductivity measurements were made over a range of temperatures, 20C to 100C. Specific heat was measured over a range of 0C to 100C. The maximum temperature of 100C was selected because it is below the temperature where material's thermal degradation occurs, and the temperature range used covers the temperatures where burn injuries occur in human skin. The thermo-optical properties data were generated only at room temperature, approximately 23C, since the test apparatus was not designed to operate at higher temperatures.
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