ASTM D2974-20e1

Standard Test Methods for Determining the Water (Moisture) Content, Ash Content, and Organic Material of Peat and Other Organic Soils

SIGNIFICANCE AND USE
5.1 This standard is used in various industries including, but not limited to, agriculture, forestry, energy, horticulture, and geotechnical. Over the years, the use of peat as a fuel has been on the decline for numerous reasons, however it is still being used as a fuel in some parts of the world. Peat typically has high a water content, thus when being used as a fuel, the peat must first be air dried in order to reduce the water content. When the peat it too wet, it doesn’t burn well and much heat is wasted in unnecessary conversion of water to steam and more smoke/soot is created, which can coat a chimney and pose a danger to the end user.  
5.2 The ash content and percent organic material are important in the following: (1) classifying peat or other organic soil, (2) geotechnical and general classification purposes, and (3) when peats are being evaluated as a fuel. The ash content is one of several parameters used to classify peat as detailed in Classification D4427.
Note 1: The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.
SCOPE
1.1 These test methods cover the measurement of water (moisture) content, ash content, and organic material in peats and other organic soils, such as organic clays, silts, and mucks. Test Method D2216 provides for determining the water (moisture) content in mineral soils and rock.  
1.2 This standard has two different ways to determine the water content of the specimen prior to determining the ash content based on the application for which the peat or organic soil is being used. For general classification of peat/organic soils not being used for fuel, the water content is determined using oven drying. For peat/organic soils being used as a fuel, the water content is determined first by air drying followed by oven drying.  
1.3 There are two Methods, A and B, for determining the ash content and organic material of peat or organic soils. For general classification purposes, Method A is used to determine the water content, ash content, and organic material. When the peat is being used as a fuel, Method B is used to determine the water content, ash content and organic material.  
1.3.1 Method A—The ash content and organic material of peat or organic soils is determined by igniting the oven-dried specimen as obtained from the water content determination in a furnace at 440 ± 40°C. This method is used for general purposes and should not be used when the peat or organic soils are being used or evaluated for use as a fuel.  
1.3.2 Method B—The ash content and organic material of peat or organic soils is determined by igniting the air-dried then oven-dried specimen obtained from the water content determination in a furnace at 750 ± 38°C. This method is used when the peat or organic soil is being used as or evaluated for use as a fuel.  
1.4 Units—The values stated in SI units are to be regarded as the standard. No other units of measurement are included in this standard.  
1.5 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.  
1.5.1 The procedures used to specify how data are collected/recorded or calculated in this standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for...

General Information

• Status: Published
• Publication Date: 14-Jan-2020
• ICS: 65.080 - Fertilizers
• Technical Committee: D18 - Soil and Rock
• Drafting Committee: D18.22 - Media for Plant Growth

Relations

• Replaces: ASTM D2974-20 - Standard Test Methods for Determining the Water (Moisture) Content, Ash Content, and Organic Material of Peat and Other Organic Soils
• Effective Date: 15-Jan-2020
• Refers: ASTM D4753-24 - Standard Guide for Evaluating, Selecting, and Specifying Balances and Standard Masses for Use in Soil, Rock, and Construction Materials Testing
• Effective Date: 01-Feb-2024
• Refers: ASTM D3740-23 - Standard Practice for Minimum Requirements for Agencies Engaged in Testing and/or Inspection of Soil and Rock as Used in Engineering Design and Construction
• Effective Date: 01-Nov-2023
• Refers: ASTM D3740-19 - Standard Practice for Minimum Requirements for Agencies Engaged in Testing and/or Inspection of Soil and Rock as Used in Engineering Design and Construction
• Effective Date: 01-Oct-2019
• Refers: ASTM D2216-19 - Standard Test Methods for Laboratory Determination of Water (Moisture) Content of Soil and Rock by Mass
• Effective Date: 01-Mar-2019
• Refers: ASTM D4427-13(2017) - Standard Classification of Peat Samples by Laboratory Testing
• Effective Date: 01-May-2017
• Refers: ASTM D4753-15 - Standard Guide for Evaluating, Selecting, and Specifying Balances and Standard Masses for Use in Soil, Rock, and Construction Materials Testing
• Effective Date: 01-May-2015
• Refers: ASTM D653-14 - Standard Terminology Relating to Soil, Rock, and Contained Fluids
• Effective Date: 01-Aug-2014
• Refers: ASTM D4427-13 - Standard Classification of Peat Samples by Laboratory Testing
• Effective Date: 01-Jul-2013
• Refers: ASTM D3740-12a - Standard Practice for Minimum Requirements for Agencies Engaged in Testing and/or Inspection of Soil and Rock as Used in Engineering Design and Construction
• Effective Date: 01-May-2012
• Refers: ASTM D3740-12 - Standard Practice for Minimum Requirements for Agencies Engaged in Testing and/or Inspection of Soil and Rock as Used in Engineering Design and Construction
• Effective Date: 01-Mar-2012
• Refers: ASTM D653-11 - Standard Terminology Relating to Soil, Rock, and Contained Fluids
• Effective Date: 01-Sep-2011
• Refers: ASTM D3740-11 - Standard Practice for Minimum Requirements for Agencies Engaged in Testing and/or Inspection of Soil and Rock as Used in Engineering Design and Construction
• Effective Date: 01-Sep-2011
• Refers: ASTM D2216-10 - Standard Test Methods for Laboratory Determination of Water (Moisture) Content of Soil and Rock by Mass
• Effective Date: 01-Jul-2010
• Refers: ASTM D3740-10 - Standard Practice for Minimum Requirements for Agencies Engaged in Testing and/or Inspection of Soil and Rock as Used in Engineering Design and Construction
• Effective Date: 01-Mar-2010

Overview

ASTM D2974-20e1 is an international standard that provides test methods for determining the water (moisture) content, ash content, and organic material in peat and other organic soils. Published by ASTM International, this standard is widely recognized and used in a range of industries, including agriculture, forestry, energy, horticulture, and geotechnical engineering. Its procedures enable the classification of peat and organic soils, and their evaluation for specific uses, such as fuel.

Reliable determination of moisture, ash, and organic content is essential for effective soil management, fuel utilization, and environmental compliance. This standard covers both general classification and fuel evaluation purposes using two specific analytical methods.

Key Topics

• Measurement Scope: Covers procedures for measuring moisture, ash, and organic material content in peat, organic soils, clays, silts, and mucks.
• Applicability: Suitable for peat and organic soils used in agriculture, geotechnical studies, and as potential fuel sources.
• Method A: Designed for general soil classification. Utilizes oven drying for moisture determination followed by ignition at 440 ± 40°C to determine ash and organic content.
• Method B: Intended for peats and organic soils considered for fuel use. Involves air drying and oven drying for moisture determination, followed by ignition at 750 ± 38°C.
• Result Reporting: Emphasizes significant digits, rounding, and accuracy, following industry-accepted practices.
• Safety and Competency: Highlights the importance of personnel proficiency and proper equipment for reliable results.

Applications

ASTM D2974-20e1 has broad practical value across several industries:

• Agriculture & Horticulture: Accurate determination of organic content and moisture is critical for soil fertility management, crop suitability assessment, and greenhouse substrate evaluation.
• Forestry: Forest soil classification and analysis rely on moisture and organic matter content data for ecological impact studies and land management.
• Energy Sector: For regions where peat is still used as a biofuel, assessing moisture and ash content is essential for optimizing combustion processes and evaluating fuel quality.
• Geotechnical Engineering: Provides key parameters for soil classification that affect construction, infrastructure design, and environmental assessment.
• Environmental Compliance: Ensures labs and practitioners can reliably compare organic soils using standardized, repeatable measurements.
• Research and Education: Supports academic studies in soil science, environmental monitoring, and land reclamation.

By standardizing the methods for measuring these critical properties, ASTM D2974-20e1 ensures consistency and comparability of data across projects, regions, and laboratories.

Related Standards

ASTM D2974-20e1 references and complements several other ASTM standards:

• ASTM D2216: Test Methods for Laboratory Determination of Water (Moisture) Content of Soil and Rock by Mass.
• ASTM D4427: Classification of Peat Samples by Laboratory Testing.
• ASTM D653: Terminology Relating to Soil, Rock, and Contained Fluids.
• ASTM D3740: Practice for Agencies Performing Soil Testing.
• ASTM D4753: Guide for Selecting Balances and Standard Masses for Soil Testing.
• ASTM D6026: Practice for Using Significant Digits in Geotechnical Data.

Organizations and labs following ASTM D2974-20e1 are encouraged to use these related references for comprehensive soil testing and classification programs.

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Keywords: ASTM D2974-20e1, peat analysis, organic soil testing, moisture content, ash content, organic material, soil classification, fuel evaluation, geotechnical testing, peat as fuel, soil laboratory standard.

Standards Content (Sample)

This 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.
´1
Designation: D2974 − 20
Standard Test Methods for
Determining the Water (Moisture) Content, Ash Content, and
Organic Material of Peat and Other Organic Soils
This standard is issued under the fixed designation D2974; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
ε NOTE—Subsection 4.1 was editorially corrected in March 2020.
1. Scope* 1.4 Units—The values stated in SI units are to be regarded
as the standard. No other units of measurement are included in
1.1 These test methods cover the measurement of water
this standard.
(moisture) content, ash content, and organic material in peats
1.5 All observed and calculated values shall conform to the
and other organic soils, such as organic clays, silts, and mucks.
guidelines for significant digits and rounding established in
Test Method D2216 provides for determining the water (mois-
Practice D6026.
ture) content in mineral soils and rock.
1.5.1 Theproceduresusedtospecifyhowdataarecollected/
1.2 This standard has two different ways to determine the
recorded or calculated in this standard are regarded as the
water content of the specimen prior to determining the ash
industry standard. In addition, they are representative of the
content based on the application for which the peat or organic
significant digits that generally should be retained. The proce-
soil is being used. For general classification of peat/organic
dures used do not consider material variation, purpose for
soils not being used for fuel, the water content is determined
obtaining the data, special purpose studies, or any consider-
using oven drying. For peat/organic soils being used as a fuel,
ations for the user’s objectives; and it is common practice to
the water content is determined first by air drying followed by
increase or reduce significant digits of reported data to be
oven drying.
commensuratewiththeseconsiderations.Itisbeyondthescope
of this standard to consider significant digits used in analysis
1.3 There are two Methods, A and B, for determining the
methods for engineering design.
ash content and organic material of peat or organic soils. For
general classification purposes, MethodAis used to determine
1.6 This standard does not purport to address all of the
the water content, ash content, and organic material. When the safety concerns, if any, associated with its use. It is the
peat is being used as a fuel, Method B is used to determine the
responsibility of the user of this standard to establish appro-
water content, ash content and organic material. priate safety, health, and environmental practices and deter-
mine the applicability of regulatory limitations prior to use.
1.3.1 Method A—The ash content and organic material of
1.7 This international standard was developed in accor-
peat or organic soils is determined by igniting the oven-dried
dance with internationally recognized principles on standard-
specimen as obtained from the water content determination in
ization established in the Decision on Principles for the
a furnace at 440 6 40°C. This method is used for general
Development of International Standards, Guides and Recom-
purposes and should not be used when the peat or organic soils
mendations issued by the World Trade Organization Technical
are being used or evaluated for use as a fuel.
Barriers to Trade (TBT) Committee.
1.3.2 Method B—The ash content and organic material of
peatororganicsoilsisdeterminedbyignitingtheair-driedthen
2. Referenced Documents
oven-dried specimen obtained from the water content determi-
nation in a furnace at 750 6 38°C. This method is used when 2.1 ASTM Standards:
the peat or organic soil is being used as or evaluated for use as D653 Terminology Relating to Soil, Rock, and Contained
a fuel. Fluids
D2216 Test Methods for Laboratory Determination of Water
(Moisture) Content of Soil and Rock by Mass
These test methods are under the jurisdiction ofASTM Committee D18 on Soil
and Rock and are the direct responsibility of Subcommittee D18.22 on Media for
Plant Growth. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Current edition approved Jan. 15, 2020. Published March 2020. Originally contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
approved in 1971. Last previous edition approved in 2014 as D2974 – 14. DOI: Standards volume information, refer to the standard’s Document Summary page on
10.1520/D2974-20E01. the ASTM website.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
´1
D2974 − 20
D3740 Practice for Minimum Requirements for Agencies 5.2 The ash content and percent organic material are impor-
Engaged in Testing and/or Inspection of Soil and Rock as tant in the following: (1) classifying peat or other organic soil,
Used in Engineering Design and Construction (2) geotechnical and general classification purposes, and (3)
D4427 Classification of Peat Samples by Laboratory Testing whenpeatsarebeingevaluatedasafuel.Theashcontentisone
D4753 Guide for Evaluating, Selecting, and Specifying Bal- of several parameters used to classify peat as detailed in
ances and Standard Masses for Use in Soil, Rock, and Classification D4427.
NOTE 1—The quality of the result produced by this standard is
Construction Materials Testing
dependent on the competence of the personnel performing it, and the
D6026 Practice for Using Significant Digits in Geotechnical
suitability of the equipment and facilities used. Agencies that meet the
Data
criteria of Practice D3740 are generally considered capable of competent
and objective testing/sampling/inspection/etc. Users of this standard are
3. Terminology cautioned that compliance with Practice D3740 does not in itself assure
reliable results. Reliable results depend on many factors; Practice D3740
3.1 Definitions:
provides a means of evaluating some of those factors.
3.1.1 For definitions of common technical terms used in this
standard, refer to Terminology D653.
6. Apparatus
6.1 Drying Oven—Vented, thermostatically controlled oven
4. Summary of Test Methods
capable of maintaining a uniform temperature of 110 6 5°C
throughout the drying chamber. The oven shall not have any
4.1 Method A—A peat or organic soil sample is reduced by
“hot spots” that could ignite the specimen. The uniformity of
quartering to obtain a 50.00 610 g test specimen. A water
the oven’s temperature shall be verified annually and the
content determination is made by drying the test specimen in a
110°C 6 5°C oven. The loss of mass due to drying is temperature should be checked or monitored as detailed inTest
Method D2216 (Note 2).
considered to be water.After oven drying, the test specimen is
placed in a furnace that is then gradually brought up to a
NOTE 2—The temperature of the drying oven is very important for
temperature of 440 6 40°C. The specimen remains in the
organicsoils.Hotspotsintheovencouldignitethespecimen.Careshould
furnace until it is completely ashed. Then it is removed and
be taken when monitoring the oven’s temperature and placement of the
specimens within the oven to avoid possible ignition.
placed in a desiccator to cool to room temperature before
determining its mass. The substance remaining after ignition is
6.2 Thermometric Device—A thermometric device(s) ca-
the ash. The water content, ash content and amount of organic
pable of measuring the temperature of the drying oven and the
material is then calculated. This method is used for general
furnace readable to 1°C or better and having an accuracy of at
purposes/classification of peats and organic soils and must not
least 61°C.
be used for peat or organic soil being used or evaluated for use
6.3 Furnace—An ignition oven or furnace capable of pro-
as a fuel.
ducing constant temperatures of 440 6 40°C and 750 6 38°C.
4.2 Method B—A peat or organic soil sample is reduced by
6.4 Balance or Scale, Balances/Scales shall conform to the
quartering to obtain a 100.0 to 300.00 g test specimen.Awater
requirements of Guide D4753. The balance/scale must have a
content determination is made by first air drying the test
minimum capacity of 500 g and have a readability without
specimen, then taking 50.00 6 10 g of air-dried peat/organic
estimation of of 0.01 g.
soil and then oven drying it in a 110°C 6 5°C oven.After oven
6.5 Non-Absorbent Surface—A rubber sheet, oil cloth, or
drying, the test specimen is placed in a furnace that is then
other similar non-absorbent material/surface.
gradually brought up to a temperature of 750°C 6 38°C. The
specimen remains in the furnace until it is completely ashed.
6.6 Container—A porcelain or high-silica crucible,
Then it is removed and placed in a desiccator to cool to room
container, or dish having a capacity of 100 mL or more is
temperature before determining its mass. The substance re-
acceptable provided its mass does not change under the
mainingafterignitionistheash.Thewatercontent,ashcontent
ignition condition. The container must have a cover. A lid is
and amount of organic material is then calculated.This method
recommended, however heavy duty aluminum foil is accept-
is used when the peat or organic soil is to be used as fuel.
able for use as a cover.
6.7 Large Pan—A330 by 230 mm or larger flat pan or tray.
5. Significance and Use
6.8 Desiccator—A desiccant containing device of suitable
5.1 This standard is used in various industries including, but
size used to prevent moisture gain during cooling of the
not limited to, agriculture, forestry, energy, horticulture, and
oven-dried specimen.
geotechnical. Over the years, the use of peat as a fuel has been
6.9 Miscellaneous Items—Items such as, water-proof
on the decline for numerous reasons, however it is still being
containers, spoons, spatulas are useful.
used as a fuel in some parts of the world. Peat typically has
high a water content, thus when being used as a fuel, the peat
7. Sampling and Test Specimens
must first be air dried in order to reduce the water content.
When the peat it too wet, it doesn’t burn well and much heat is 7.1 T
...