Temperature offsets to the wet bulb, globe temperature index (WBGT), used to provide guidance for work/rest cycles and fluid replacement for Soldiers in the field wearing standard military uniforms, were developed for increased heat stress wearing protective equipment. This report details how those offsets were determined, and shows the basis for the revised offsets in the current TBMED 507. A computer simulation (USARIEM-EXP) was used to calculate core temperatures in a Soldier wearing the Hot Weather BDU, MOPP 1, and MOPP 4 at a WBGT temperature of 86°F, at two work intensities. Core temperature responses at lower WBGT temperatures were then simulated until the core temperature for Soldiers in MOPP 4 was equivalent to that in the BDU at WBGT 86°F. Similar comparisons were made for soldiers wearing the BDU with body armor in compensable and uncompensable hot environments. Findings indicate that compared to wearing only the BDU, WBGT temperatures should be offset by: (1) + 10° F at light work in MOPP 4, (2) + 20°F at moderate work in MOPP 4, (3) no adjustment if skin is dry in body armor with the BDU, and (4) + 5° F if skin is wet in body armor with the BDU.