This test method covers the determination of the blocking resistance of flexible types of packaging materials, including paper, paperboard, and the impregnated, coated or laminated, or coated and laminated, combinations of paper with metallic foils and synthetic films that may be produced therefrom, but is applicable to papers in general, whenever a tendency to block is important. The test method provides a range of standard conditions which is designed to simulate varying climatic conditions that may be encountered in the manufacture, storage, transportation, or use of the materials. The test apparatus includes the following: oven, desiccator, bedplates, pressure blocks, and interleaving material. Eight test specimens shall be cut from each sample for each set of the test conditions to be used. One or more of the specified sets of conditions of bulb temperature, relative humidity, and pressure shall be used. The methods of sampling and specimen conditioning are given and the procedure of determining the degree of blocking resistance (no blocking, slight blocking, or considerable blocking) is detailed.

1.1 This test method covers the determination of the blocking resistance of flexible types of packaging materials, including paper, and the impregnated, coated or laminated, or coated and laminated, combinations of paper with metallic foils and synthetic films that may be produced therefrom, but is applicable to papers in general, whenever a tendency to block is important. The test method provides a range of standard conditions of temperature and relative humidity at constant pressure for a specified time which is designed to simulate varying climatic conditions that may be encountered in the manufacture, storage, transportation, or use of the materials.

1.2 The values stated in inch-pound units are to be regarded as the standard. The values in parentheses are for information only.

1.3 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.