Значение и использование

This practice provides a means by which samples of geosynthetics may be selected to provide a statistically valid sample for the selection of test specimens without previous knowledge of the variability that may exist between production units.

The principles stated in Practice D 4271, and the illustrative text in that practice can be used by test method authors in preparing sampling statements.

This practice gives three procedures for sampling: one for manufacturer's quality control (MQC), one for manufacturer's quality assurance (MQA) testing, and a third for purchaser's specification conformance testing. For this reason, test methods containing a section on sampling that requires the use of this practice should contain a statement in the section on reporting similar to the following:“ Report which procedure from Practice D 4354 was used for sampling: Procedure A for Manufacturer's Quality Control (MQC), Procedure B for Manufacturer's Quality Assurance (MQA) Testing, or Procedure C for Purchaser's Specification Conformance Testing.

Manufacturer's Quality Assurance is done internally to ensure the manufacturer of the MQC program. When it is required to provide certification to a purchaser as to quality assurance, the MQA testing is to be done by an external MQA testing facility.

Область применения

1.1 This practice covers three procedures for the sampling of geosynthetics for testing. This practice requires that instructions on taking laboratory samples and test specimens be part of every test method for geosynthetics.

1.1.1 The first procedure describes the sampling of production units for the purpose of manufacturer's quality control (MQC) (Table 1).

1.1.2 The second procedure describes the sampling of production units for the purpose of manufacturer's quality assurance (MQA) testing during the manufacturing process. This requires that backup statistical process control records be maintained during the manufacturing process (Table 2).

1.1.3 The third procedure describes the division of shipments of geosynthetics into lots and the determination of lot sample size for purchaser's specification conformance testing (Table 3).

1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

TABLE 1 Number of Units to be Selected as Lot Sample—Purchaser's Specification Conformance

Number of Units in LotNumber of Units Selected 1 to 2 1 3 to 8 2 9 to 273 28 to 644 65 to 1255 126 to 2166 217 to 3437 344 to 5128 513 to 7299 730 to 100010 1001 or more11

TABLE 2 Number of Units to be Selected as Lot Sample—Manufacturer's Quality Assurance

Number of Units in LotNumber of Units Selected 1 to 2001 201 to 5002 501 to 10003 1001 or more4

TABLE 3 Number of Units to be Selected as Lot Sample—Purchaser's Specification Conformance

Number of Units in LotNumber of Units Selected 1 to 2001 201 to 5002 501 to 10003 1001 or more4