---
title: "ASTM D4921"
url: "https://mat-cs.com/astm-d4921/"
description: "This test method applies to a simple shake test for evaluating the tendency of an aqueous solution of engine coolant to foam at room temperature."
---

ASTM Standard

# ASTM D4921

Standard Test Method for Foaming Tendencies of Engine Coolants at Room Temperature

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## Significance and Use

4.1 The test method will generally identify coolants that have a tendency to foam excessively at room temperature.

Note 1: In use, the foaming tendency of a coolant solution may be increased by service aging or contamination.

## Scope

1.1 This test method applies to a simple shake test for evaluating the tendency of an aqueous solution of engine coolant to foam at room temperature.

1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.