---
title: "ASTM C40"
url: "https://mat-cs.com/astm-c40/"
description: "This test method is used in making a preliminary determination of the acceptability of fine aggregates with respect to the requirements of Specification C33/C33M that relate to organic impurities."
---

ASTM Standard

# ASTM C40

Standard Test Method for Organic Impurities in Fine Aggregates for Concrete

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## Significance and Use

4.1 This test method is used in making a preliminary determination of the acceptability of fine aggregates with respect to the requirements of Specification C33/C33M that relate to organic impurities.

4.2 The principal value of this test method is to furnish a warning that injurious amounts of organic impurities may be present. When a sample subjected to this test produces a color darker than the standard color it is advisable to perform the test for the effect of organic impurities on the strength of mortar in accordance with Test Method C87/C87M.