ASTM C 1904 : 2020

1.1This standard presents test methods for the determination of the effects of biogenic acidification on concrete products and/or efficacy of antimicrobial products to resist microbially-induced corrosion (MIC) of concrete. In these tests, the biogenic acidification is achieved by sulfur-oxidizing bacteria (SOB) that can convert elemental sulfur or thiosulfate to sulfuric acid without the use of H₂S gas.

1.2This standard is referenced in the guideline document for MIC of concrete products. Guide C1894 provides guidance for microbially-induced corrosion of concrete products and an overview of where this test, and its options, can and should be used. This document is not intended to be a guideline document for MIC of concrete products.

1.3This standard does not cover controlled breeding chamber tests, in which H₂S gas is produced by bacterial activity and acidification is the result of the conversion of this H₂S gas to sulfuric acid.

1.4This standard does not cover chemical acid immersion tests, in which acidification is achieved by chemical sulfuric acid addition, not by bacterial activity. Testing protocols for chemical acid immersion are described in Test Methods C267 and C1898.

1.5This standard does not cover tests that assess field exposure conditions or sewage pipe, concrete tank, or concrete riser network design.

1.6This standard does not cover live trial tests where concrete coupons or other specimens are monitored in sewers.

1.7The tests described in this standard should not be performed on concrete samples that have already been exposed to MIC conditions.

1.8This standard does not cover concrete deterioration due to chemical sulfate attack, which is caused by the reaction of sulfate compounds that exist in wastewater with the hydration products of cement. Test methods for assessing sulfate attack are provided by Test Methods C452 and C1012/C1012M.

1.9The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.10This 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.11This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.