CAN/CGSB 4.2 NO. 9.3-M90 (R2013) PDF

This method determines the breaking strength of fabrics by the ravelled strip method. It is intended primarily for testing high-strength materials that are difficult to grip in the clamps of the testing machine and that cannot be tested satisfactorily by CAN/CGSB-4.2 No. 9.1-M.

This method may be used to estimate the breaking strength of a given width of a fabric by testing narrower specimens of at least two different widths. (When stress is applied to strip specimens, yarns at the sides of the specimen frequently slip out of the crosswise yarns, lose their crimp and consequently may not break at the same extension as the central yarns. Since not all yarns break, the result obtained may not be the true breaking strength for the width of fabric represented by the specimen. This "edge effect," due to the yarns which do not break, is substantially independent of the width of specimen and it is therefore possible to calculate the breaking strength per unit width of fabric from the results for specimens of two different widths. When the strength of the selvages differs appreciably from that of the yarns in the body of the fabric, the strength of the full width of the body of fabric cannot be calculated accurately from the results of tests made on the narrower specimens.)

The procedure is applicable to fabrics either in the conditioned state or when wet.

The procedure may be used with constant-rate-of-extension (CRE) type (e.g., strain gauge) or constant-rate-of-traverse (CRT) type (e.g., pendulum) tensile testing machines.

This method may require the use of materials and/or equipment that could be hazardous. This document does not purport to address all the safety aspects associated with its use. Anyone using this method has the responsibility to consult the appropriate authorities and to establish appropriate health and safety practices in conjunction with any existing applicable regulatory requirements prior to its use.