ESS Conducts Compliance Tests for Sulfuric Acid Mist Using NCASI 8a (Controlled Condensate Method)

Environmental Source Samplers, Inc. (ESS) has had success utilizing alternative methodologies in sampling for Sulfuric Acid Mist (H2SO4).

Wilmington, NC, June 13, 2014 --( Environmental Source Samplers, Inc. (ESS), an air-testing firm based in Wilmington, North Carolina, has had success utilizing alternative methodologies in sampling for Sulfuric Acid Mist (H2SO4). This pollutant is typically measured utilizing EPA Method 8, and more facilities are beginning to have testing requirements in recent years.

Method 8 utilizes the principle of selective solvent absorption (SSA) to capture sulfur trioxide (SO3) and H2SO4 in an isopropyl alcohol (IPA) solution. A drawback to this method, however, is the absence of a filter to effectively remove PM and other pollutants prior to the capture of H2SO4. This can lead to interference from other filterable particulates and pollutants, such as ammonia, which can result in emissions reading much higher than expected.

NCASI Method 8a, originally Conditional Test Method (CTM)-013, was developed as an alternative to EPA Method 8, and uses a heated quartz filter for capturing particulates, thereby eliminating the potential for interference from particulate sulfate and other interference. For sources that are having trouble with obtaining low emissions of H2SO4, and particularly those that have been using ammonia-injection control technology, the use of this method can result in a significant reduction in reported emissions from the source, by removing these varying interferences.

The method requires up-front costs due to specialized equipment, but ESS has the equipment and experience needed to conduct this test method for facilities that are currently or potentially regulated for H2SO4. ESS has requested and received variances from state regulators for use on biomass boilers, paper mills, and ceramic kilns for compliance-level testing. In all cases so far, the use of this alternative method has greatly improved the reported emissions of H2SO4, and helped their clients achieve compliance with the emissions standards to which their units are subject.

A facility that is expected to be regulated for sulfuric acid mist will need a testing partner that can achieve the best results. To learn more about ESS, visit or call 910-799-5055.
Environmental Source Samplers, Inc.
Brian Mellor