Standard Test Methods for Cobalt in Water

D 3558 - 08: Standard Test Methods for Cobalt in Water

Ensuring the purity and safety of water resources is paramount across numerous industries. For professionals responsible for water quality, accurately quantifying trace elements like cobalt is an essential task. ASTM D 3558 - 08, "Standard Test Methods for Cobalt in Water," provides the authoritative guidance needed for this critical analysis, offering proven methods to ensure compliance and protect public health and environmental integrity.

What is D 3558 - 08?

ASTM D 3558 - 08 is an industry-leading standard that outlines comprehensive procedures for determining cobalt concentrations in water. Developed by ASTM International, this document establishes three distinct atomic absorption spectrophotometry methods to accurately measure dissolved and total recoverable cobalt across various water matrices. Its primary purpose is to provide reliable, reproducible analytical techniques for laboratories and environmental professionals.

Scope & Purpose

This standard governs the analytical determination of cobalt in water and wastewater samples. It specifically covers three atomic absorption spectrophotometry techniques: direct aspiration, chelation-extraction, and graphite furnace atomization, each tailored for different concentration ranges and sample types. The scope includes reagent water, potable water, river water, wastewater, and seawater. Users are responsible for verifying the applicability of these methods to unique sample matrices. The standard does not cover sample collection procedures, which are referenced in other ASTM standards.

Who Must Comply?

• • Primary audience: Environmental scientists, analytical chemists, water quality technicians, and laboratory technicians involved in water analysis.
• • Industries affected: Water utilities, environmental testing laboratories, industrial manufacturing, municipal government, and research and development sectors.
• • Compliance nature: While often voluntary, compliance is frequently mandated by regulatory bodies or client specifications, making it effectively required for many operational contexts.
• • Enforcement: Compliance is typically overseen by environmental regulatory agencies, internal quality assurance departments, and third-party accreditation bodies.

Key Requirements Overview

• • The standard requires the use of atomic absorption spectrophotometry for cobalt determination, offering three distinct methodologies to accommodate varying concentration levels.
• • Professionals must ensure that reagents used are of high purity, conforming to ACS specifications or equivalent, to maintain analytical accuracy.
• • Key provisions include detailed procedures for sample preparation, including acid digestion for total recoverable cobalt and filtration for dissolved cobalt.
• • Users are instructed to implement appropriate safety precautions, as outlined within the standard and by general laboratory safety practices.
• • The standard emphasizes the analyst's responsibility to validate the chosen method for the specific water matrix being analyzed.

Related Standards & References

ASTM D 3558 - 08 works in conjunction with other essential ASTM standards. ASTM D 1193, Specification for Reagent Water, is critical for preparing standards and ensuring the purity of water used in analyses. ASTM D 3370, Practices for Sampling Water from Closed Conduits, and Practice D 1066 provide guidance on proper sample collection to ensure representative results. Furthermore, ASTM D 2777, Practice for Determination of Precision and Bias, offers context for evaluating the reliability of the analytical data generated by these test methods.