This part of EN 28510 specifies a 90° peel test for the determination, under specified conditions, of the peel resistance of a bonded assembly of two adherends where at least one adherend is flexible. If a normal tensile testing machine is used for the test, the peel angle will not be constant at exactly 90°. If a constant angle of exactly 90° is required, a roller peeling device is used (see 4.1). The 90° peel test is particularly suitable for use with less flexible adherends for which a 180° peel test is not suitable because the adherends crack, break or delaminate. A 180° peel test is described in EN ISO 8510-2.