Modern technological developments have brought with them a vast increase in the kinds of hazard to which workers are exposed. Most of these hazards are encountered in work-places. Work-place hazards can be grouped in chemical,mechanical, radiation, biological, and thermal hazards.
Personal protective equipment, which includes personal protective clothing and gear such as respirators, face masks, and other controls, forms a barrier between the person and the hazardous environment. The dangers are frequently so specialized that no single type of clothing will be adequate for work outside the normal routine. Protective clothing made from woven, knitted, and nonwoven fabrics have been designed to suit specific requirements, and performance-evaluation techniques to simulate the workwear conditions have been developed.
To overcome thermal hazards, heat and flame resistant fibers are used to produce thermal protective clothing. Thermal protective clothing should not ignite,they should remain intact, not shrink,melt, or form brittle chars that may break open and expose the wearer; and they should provide as much insulation against heat as is consistent with not diminishing the wearer’s ability to perform a task. In Table1, there are some occupations in which the hazards from heat and flame are such an integral part of the job that the worker needs to wear protective clothing more or less continuously.
Total heat energy from a fire can cause a worker’s clothing to ignite or melt; it can cause the clothing to break open and subsequently cause severe burns to skin. The work of Stoll and Chianta in the 1960’s helped to quantify the response of human skin and tissue to a source of heat energy.When human tissue is raised from the normal blood temperature of 36.5 oC to 44 oC, skin burns begin to occur, at a rate that depends on the raised temperature level. For example, at 50 oC, damage to the skin is 100 times faster than at 45 oC,and at 72oC total destruction of the epidermis occurs almost instantaneously.
The growing concern regarding health and safety of workers in various sectors of the industry has generated regulations and standards, environmental and engineering controls, as well as tremendous research and development in the area of personal protective equipment. There are a number of different tests used for evaluating thermal characteristics of protective clothing, such as ease-of-ignition tests, flammability tests, heat-release-measurement tests, extinguishability tests, tests for measuring thermal insulative properties of fabrics and thermo-person full scale garment burns.
In this study, we aimed to select the most appropriate fabric or fabric assembly for usein producing thermal protective clothing, although this was not a fullscale analysis. To achieve this aim, a thermal analysis of thermal protective fabrics and assemblies was made. For this analysis, we used the thermal protective performance (TPP) test method,which is an important test method for measuring thermal protective fabric’s insulative properties. We constructed a test apparatus at our department based on the above-mentioned test method . Secondly,to see how the fabrics change during use,a series of washings was carried out. After the washings, the air permeability, area masses, dimensional changes, tear strengths and TPP ratings of the fabrics were measured.
