ASTM D3776 – Standard Test Methods for Mass Per Unit Area (Weight) of Fabric
These test methods cover the measurement of fabric mass per unit area (weight) and is applicable to most fabrics. There are four approved options in the measurement of fabric mass per unit area: Option A, Option B, Option C, and Option D. Option A may be used for acceptance testing of commercial shipments since it has been used extensively in the trade. The second option is Option B which is applicable to a full-width sample cut from a full piece, roll, bolt, or cut. Unless otherwise specified, these results will include selvages and will be on the basis of conditioned fabric. Option C on the other hand is applicable when a small swatch of fabric is sent to the laboratory to be used as the test specimen. The results are considered to be applicable to the sample only and not necessarily to the lot from which the sample was taken. Measurements by this method do not include selvages and should be reported as such, unless a selvage allowance is specified. The last option is Option D which is intended for use with narrow fabrics as so designated by the trade.
1.1 These test methods cover the measurement of fabric mass per unit area (traditionally referred to as “fabric weight”) and are applicable to most fabrics.
1.2 There are four approved options:
1.2.1 Option A—Full Piece, Roll, Bolt or Cut (Section 7).
1.2.2 Option B—Full Width Sample (Section 8).
1.2.3 Option C—Small Swatch of Fabric (Section 9).
1.2.4 Option D—Narrow Fabrics (Section 10).
1.3 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.