The purpose of this test method is to establish a common method by which manufacturers and users of ASTM hydrometers inspect, verify, or calibrate their hydrometers.

The goal is to provide a standard method that is simple, easily understood, and will produce reliable results.

1.1 This test method describes the principles, apparatus, and procedures for the inspection, calibration, and verification of ASTM glass hydrometers. This test method is applicable to ASTM hydrometers and may be used for other general hydrometers of the constant-mass, variable-displacement type.

User must determine the applicability of this method for hydrometers other than ASTM hydrometers. Method studies were completed for ASTM hydrometers only and the precision and bias statements were developed using ASTM hydrometers only. References to other types of hydrometers are for user information only.

1.2 The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. The metric equivalents of inch-pound units may be approximate.

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.