A laboratory study was conducted to determine if a T-peel test was sensitive to differences in initial (7 days) bond strength for adhesive-bonded seams of EPDM (ethylene propylene diene terpolymer) rubber membranes made under different application conditions. The main categories of application parameters investigated were: surface condition (cleanness, moisture) of the rubber; pressure applied; temperature during seam formation; open time. The T-peel test was found to be sensitive to changes in bond resulting from variation of some of the application parameters. Seams prepared using uncleaned sheets (without removing the talc or other contaminants from their surfaces), or using long open times, had lower average peel strengths than those of the control specimens. Light pressure or high temperature during bond formation produced seams with average peel strengths higher than those of the controls. Wet surfaces and low temperature had no significant effect on the average strength of the seams.