The freezing point of an engine coolant indicates the coolant freeze protection.

The freezing point of an engine coolant may be used to determine the approximate glycol content, provided the glycol type is known.

Freezing point as measured by Test Method D 1177 or approved alternative method is a requirement in Specifications D 3306 and D 6210.

This test method provides results that are equivalent to Test Method D 1177 and expresses results to the nearest 0.1°C with improved reproducibility over Test Method D 1177.

This test method determines the freezing point in a shorter period of time than Test Method D 1177.

This test method removes most of the operator time and judgement required by Test Method D 1177.

1.1 This test method covers the determination of the freezing point of an aqueous engine coolant solution.

1.2 This test method is designed to cover ethylene glycol base coolants up to a maximum concentration of 60 % (v/v) in water; however, the ASTM interlaboratory study mentioned in 12.2 has only demonstrated the test method with samples having a concentration range of 40 to 60 % (v/v) water.

Note 1—Where solutions of specific concentrations are to be tested, they shall be prepared from representative samples as directed in Test Method D 1176. Secondary phases separating on dilution need not be separated.

Note 2—The products may also be marketed in a ready-to-use form (prediluted).

1.3 The values stated in SI units are to be regarded as the standard. The values given in parenthesis are for information only.

1.4 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.