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Updated: Oct 25, 2025
13:48
Design and Construction of an Urban Runoff Research Facility
Published on: August 8, 2014
13.2K
Development of a Standard Reference Material for Rainwater Analysis.
William F Koch1, George Marinenko1, Robert C Paule1
1National Bureau of Standards, Gaithersburg, MD 20899.
Summary
A new Standard Reference Material (SRM) 2694, "Simulated Rainwater," was developed to improve acidic rainfall analysis. This material aids in accurately measuring key components in environmental monitoring.
Area of Science:
- Environmental Science
- Analytical Chemistry
- Materials Science
Background:
- Acidic rainfall poses environmental risks, necessitating accurate monitoring.
- Standardized reference materials are crucial for validating analytical methods in environmental analysis.
Purpose of the Study:
- To develop and characterize a Standard Reference Material (SRM) for simulated rainwater.
- To provide certified values for key chemical components in simulated rainwater samples.
Main Methods:
- Formulation and preparation of two levels of simulated rainwater solutions (SRM 2694-I and 2694-II).
- Analysis of 12 components using 10 different analytical techniques.
- Statistical evaluation of analytical data to establish recommended values.
Main Results:
- SRM 2694,
- Simulated Rainwater,
- was successfully developed.
- Recommended values for pH, specific conductance, acidity, and 10 ionic components were determined.
- Instability of ammonium ion in acidic solutions was noted and discussed.
Conclusions:
- SRM 2694 provides a reliable standard for the analysis of acidic rainfall.
- The material supports accurate measurement of critical rainwater constituents.
- Specific recommendations are provided for the use of SRM 2694, especially for pH measurements.
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