The decomposition of flame resistant (FR) materials, either through elevated temperature or contact with flames, results in a range of chemical species, some of which can be quite toxic to humans. Small scale or bench scale tests for decomposition products have been done in the past, but there were always questions as to whether these were representative of full-scale flash fire test results. To determine whether the decomposition products would be of sufficient quantity to measure and whether different FR materials would produce a "signature" set of compounds, full scale testing was undertaken. Coveralls constructed from four common FR materials were evaluated. The methodology used allowed the determination of the thermal decomposition products of FR materials when exposed to flash fire.
This study explores the behavior of textile fabrics under thermal exposures. The performance of thermal protective textile fabric systems with different structural features was evaluated under laboratory simulated thermal exposures. The study demonstrated that the protective performance of textile fabric systems varies with different types of thermal exposure. To provide effective protection in flame and radiant-heat exposures, the most important fabric properties to address are emissivity, absorptivity and thermal resistance. In hot surface exposures, the compression property of the fabric systems is the primary feature to consider for protection. Hot water and steam exposures produce mass transfer through fabrics. In the presence of water or steam jet pressure, fabric compression is a primary factor in protecting the human body. The findings obtained in this study can be used to engineer fabric systems that provide better protection from various thermal exposures.
A laboratory simulation was performed to study the thermal protective performance of fabric systems under low level thermal hazards in the range of 6.3-8.3 kW/m(2). Two approaches were used. The first used a method similar to the ASTM F 1939, radiant heat resistance test, while the second used a modification designed to capture the contribution to skin burn injury due to energy stored in the test specimens being released after the direct exposure had ended. Both dry and wet specimens were tested. In order to accommodate the prolonged exposure time a water cooled heat flux sensor was used to calibrate the radiant heat source and measure the energy directly transmitted through during the exposure and discharged later from the fabric systems. The Henriques Burn Integral (HBI) was adopted and programmed with a three layer skin model to predict the time required to achieve a second degree skin burn injury. The study investigated the thermal protection provided by the clothing with different layering and examined the effect of moisture under low level radiant heat exposures. In addition, the physiological burden associated with wearing the clothing was predicted and compared. The results obtained show the difference in measured protection level under low radiant heat from these two approaches and demonstrate that the stored thermal energy released from the clothing system significantly lowers the measured thermal protective performance.
Extensive use of pressurized steam in the oil and gas sectors has led to incidents where workers were seriously injured. In this study a test device and procedure to measure heat transfer through fabrics during steam exposure were developed and evaluated. Several factors were considered while designing the test device to simulate work site conditions. Fabrics were exposed to steam at 2 distances (50 and 100 mm) and 2 pressures (207 and 69 kPa). Theoretical considerations included heat and mass transfer, and fabric structure and performance properties. The test device and procedure differentiated well among both fabrics and exposure conditions. For all fabrics, maximum heat transfer was observed at highest steam pressure and shortest distance. Laminated and coated fabrics performed better than a fabric without such treatments.