ASTM D5931-20 (2025) PDF

Full title and description

St ASTM D5931-20 (2025) — Standard Test Method for Measuring Odor and Taste Potentials of Water and Water Purification Processes. This standard specifies procedures for sensory evaluation and instrumental approaches to assess odor and taste potentials in potable, process, and treated waters, and for evaluating water treatment and purification process performance with respect to organoleptic quality.

Abstract

This standard provides methods to detect, quantify, and characterize odor and taste potentials in water using both sensory panel techniques and recommended instrumental or chemical screening methods. It covers sample collection, panel selection and training, presentation protocols, scoring scales, and interpretive guidance to aid in identifying causes and tracking changes in organoleptic properties related to treatment operations, distribution systems, and source water variations.

General information

• Status: Current (as referenced with a 2025 reaffirmation/citation)
• Publication date: 2020 (designation D5931-20); referenced/marketed 2025 edition
• Publisher: ASTM International
• ICS / categories: 13.030 (Water quality) / Environmental and drinking water testing
• Edition / version: D5931-20 (2020) — cited as the active edition with 2025 reference
• Number of pages: Typically 8–16 pages (standard test method length; actual page count may vary by publication format)

Scope

The scope of this standard covers procedures for assessing odor and taste potentials of water and related purification processes. It applies to raw, treated, and distribution system waters where organoleptic properties are of concern. Included are sensory panel methods (triangle, paired-comparison, intensity scaling) and recommendations for sample handling, storage, and presentation. The standard is intended for use in operational monitoring, source water investigations, process optimization, and complaints investigation where human perception of water quality is relevant.

Key topics and requirements

• Definitions of odor and taste potential terms and descriptors used in sensory evaluation.
• Requirements for selection, training, and qualification of sensory panelists, including screening criteria and performance monitoring.
• Procedures for sample collection, preservation, storage times, and conditions to minimize alteration of organoleptic constituents.
• Standardized sample presentation methods (blinded, randomized), test formats (triangle tests, paired comparisons, intensity scaling), and scoring systems.
• Guidance on statistical analysis of panel data, interpretation of significance, and reporting formats.
• Recommendations for complementary instrumental or chemical analyses to identify likely causal compounds (e.g., geosmin, MIB, sulfur compounds) and for correlating sensory results with analytical data.
• Quality control, documentation, and safety recommendations for conducting sensory testing.

Typical use and users

Utilities, water and wastewater laboratories, environmental consultants, potable water treatment plant operators, research laboratories, public health agencies, and sensory testing laboratories use this standard. Typical uses include routine monitoring of treated water palatability, troubleshooting taste and odor complaints, validation of treatment process changes, source water impact studies, and research on compounds contributing to off-flavors and odors.

Related standards

Related standards and guidance commonly used alongside this test method include other ASTM methods for taste and odor, ISO and EPA guidance on sensory methods and odor assessment, and analytical standards for specific compounds (such as geosmin and 2-methylisoborneol). Standards for sampling, sample preservation, and laboratory quality management for water testing are also relevant.

Keywords

odour, odor, taste, organoleptic, sensory evaluation, water quality, potable water, water treatment, panel testing, D5931, geosmin, MIB, taste and odor potential

FAQ

Q: What is this standard?

A: It is ASTM D5931-20, a test method describing procedures to evaluate the odor and taste potentials of water and water purification processes using sensory panel techniques and recommended complementary analyses.

Q: What does it cover?

A: It covers panel selection and training, sample collection and handling, presentation methods (triangle, paired, intensity scaling), data analysis, interpretation, and guidance on linking sensory observations to analytical testing for responsible compounds.

Q: Who typically uses it?

A: Water utilities, environmental and analytical laboratories, consultants, treatment plant operators, researchers, and regulatory or public health bodies that need to assess or monitor organoleptic quality of water.

Q: Is it current or superseded?

A: The standard designation D5931-20 indicates the 2020 issue. It is treated here as the current active edition with references as of 2025. Users should check with the publisher for any amendments or newer revisions.

Q: Is it part of a series?

A: It is part of ASTM’s collection of water quality and analytical test methods; it complements other ASTM and industry standards addressing sampling, chemical analysis of off-flavor compounds, and sensory methodologies.

Q: What are the key keywords?

A: Odor, taste, organoleptic, sensory panel, water quality, D5931, geosmin, MIB, taste and odor potential.