Two prototype protective clothing systems for wildland firefighters were developed for comparison with protective clothing systems currently used by the California Department of Forestry and Fire Protection (CDF) and the U.S. Forest Service (USFS). The four types of protective clothing systems, in two different sizes, were tested for protective capabilities on the thermal mannequin at the University of Alberta, Edmonton, Alberta, Canada. An average heat flux of 80 KW/m2 and an exposure time of 4 seconds were used to simulate a wildland flash fire. A two-way analysis of variance indicated that differences in fit did not produce significant differences in burn injuries. However, it should be noted that the difference in fit in this study was relatively small. The differences in type of garment system were significant; all of the two-layer systems were significantly more protective than the one-layer system. Design features that appeared to increase thermal protection included an adjustable collar, zipper guard and reduction in loose edges on the protective shirt.