This research shows that standard bench-scale flammability tests, including ASTM D6413, Standard Test Method for Flame Resistance of Textiles (Vertical Test), do not provide reliable prediction of the after-flame behavior of flame-resistant (FR) coveralls in fire manikin tests. After-flame time, measured on a manikin or in a bench-scale test, does not correlate with garment thermal protective performance, as indicated by predicted manikin skin burns. Because they overestimate thermal shrinkage, bench-scale shrinkage tests do not accurately predict thermal shrinkage in manikin tests. This is a significant finding, because it indicates that reliance on 500°F thermal shrinkage data may lead to misleading comparative assessments of material shrinkage when constrained by a manikin body form. Although they do not accurately measure the extent of thermal shrinkage at the garment level, some small-scale shrinkage measures do correlate with garment shrinkage in manikin tests. Thermal shrinkage measured in the cylindrical TPP tests more strongly correlates with manikin measures of shrinkage than the 500°F oven test. For the FR materials studied, the 500°F oven shrinkage test did not prove to be a useful tool for predicting skin burn protection in fire manikin tests.