ASTM D5495-21

Standard Practice for Sampling with a Composite Liquid Waste Sampler (COLIWASA)

SIGNIFICANCE AND USE
5.1 This practice is applicable to sampling liquid wastes and other stratified liquids. The COLIWASA is used to obtain a vertical column of liquid representing an accurate cross section of the sampled material. To obtain a representative sample of stratified liquids, the COLIWASA should be open at both ends so that material flows through it as it is slowly lowered to the desired sampling depth. The COLIWASA must not be lowered with the stopper in place. Opening the stopper after the tube is submerged will cause material to flow in from the bottom layer only, resulting in gross over-representation of that layer.  
5.2 This practice is to be used by personnel acquiring samples.  
5.3 This practice should be used in conjunction with Guide D4687 which covers sampling plans, safety, QA, preservation, decontamination, labeling, and chain-of-custody procedures; Practice D5088 which covers decontamination of field equipment used at waste sites; Practice D5283 which covers project specifications and practices for environmental field operations; and Practice D5743 which covers drum sampling.
SCOPE
1.1 This practice describes the procedure for sampling liquids with the composite liquid waste sampler, or “COLIWASA.” The COLIWASA is an appropriate device for obtaining a representative sample from stratified or unstratified liquids. Its most common use is for sampling containerized liquids, such as tanks, barrels, and drums. It may also be used for pools and other open bodies of stagnant liquid.  
Note 1: A limitation of the COLIWASA is that the stopper mechanism may not allow collection of approximately the bottom 2.54 cm (1 in.) of material, depending on construction of the stopper.  
1.2 The COLIWASA should not be used to sample flowing or moving liquids.  
1.3 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026. Reporting of test results in units other than SI shall not be regarded as nonconformance with this standard.  
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.5 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.

General Information

• Status: Published
• Publication Date: 30-Apr-2021
• ICS: 13.030.20 - Liquid wastes. Sludge
• Technical Committee: D34 - Waste Management
• Drafting Committee: D34.01.03 - Sampling Equipment

Relations

• Refers: ASTM D5681-23 - Standard Terminology for Waste and Waste Management
• Effective Date: 01-Nov-2023
• Refers: ASTM D5088-20 - Standard Practice for Decontamination of Field Equipment Used at Waste Sites
• Effective Date: 01-May-2020
• Refers: ASTM D5681-18 - Standard Terminology for Waste and Waste Management
• Effective Date: 01-Nov-2018
• Refers: ASTM D5283-18 - Standard Practice for Generation of Environmental Data Related to Waste Management Activities: Quality Assurance and Quality Control Planning and Implementation
• Effective Date: 01-May-2018
• Refers: ASTM D5681-17 - Standard Terminology for Waste and Waste Management
• Effective Date: 01-Sep-2017
• Refers: ASTM D5681-16a - Standard Terminology for Waste and Waste Management
• Effective Date: 01-Nov-2016
• Refers: ASTM D5681-16 - Standard Terminology for Waste and Waste Management
• Effective Date: 01-Feb-2016
• Refers: ASTM D5088-15a - Standard Practice for Decontamination of Field Equipment Used at Waste Sites
• Effective Date: 01-Aug-2015
• Refers: ASTM D5088-15 - Standard Practice for Decontamination of Field Equipment Used at Waste Sites
• Effective Date: 15-Jan-2015
• Refers: ASTM D5681-13 - Standard Terminology for Waste and Waste Management
• Effective Date: 01-Feb-2013
• Refers: ASTM D5681-09 - Standard Terminology for Waste and Waste Management
• Effective Date: 01-Jul-2009
• Refers: ASTM D5283-92(2009) - Standard Practice for Generation of Environmental Data Related to Waste Management Activities: Quality Assurance and Quality Control Planning and Implementation
• Effective Date: 01-Feb-2009
• Refers: ASTM D5743-97(2008) - Standard Practice for Sampling Single or Multilayered Liquids, With or Without Solids, in Drums or Similar Containers
• Effective Date: 01-Oct-2008
• Refers: ASTM D5088-02(2008) - Standard Practice for Decontamination of Field Equipment Used at Waste Sites
• Effective Date: 15-Sep-2008
• Refers: ASTM D5681-08 - Standard Terminology for Waste and Waste Management
• Effective Date: 01-Sep-2008

Overview

ASTM D5495-21: Standard Practice for Sampling with a Composite Liquid Waste Sampler (COLIWASA) establishes recommended procedures for obtaining representative samples from stratified and unstratified liquid wastes. Developed by ASTM, this standard guides users on how to properly use a COLIWASA, a specialized device designed for obtaining vertical samples from tanks, drums, and other containers of liquid waste. Accurate sampling is essential for proper environmental management, regulatory compliance, and subsequent chemical analysis.

Key Topics

• COLIWASA Principles: The standard outlines how a COLIWASA should be used to gather a true cross-section of a liquid waste sample, emphasizing the importance of keeping both ends of the sampler open while lowering it to avoid bias toward specific liquid layers.

• Applicability: Provides procedures for sampling containerized liquids, such as barrels and drums, as well as pools or open bodies of stagnant (non-flowing) liquid; it is not suitable for moving or flowing liquids.

• Container and Equipment Requirements: Recommendations for selecting sampling equipment and containers constructed from materials compatible with the waste being sampled, as well as the importance of using clean, decontaminated equipment in accordance with related ASTM practices.

• Safety and Documentation: Stresses the operator’s responsibility for complying with relevant safety, health, and environmental protocols, and maintaining accurate documentation for sample labeling and chain-of-custody.

Applications

ASTM D5495-21 is widely used across industries and environmental sectors responsible for waste management and hazardous material handling:

• Environmental Site Investigations: Focuses on obtaining representative liquid waste samples at contaminated sites for characterization and risk assessment.
• Waste Drum Sampling: Commonly applied in situations where containerized liquid wastes must be analyzed prior to disposal, treatment, or transport.
• Compliance Monitoring: Supports regulatory compliance by ensuring samples of stratified liquids accurately reflect all layers present, essential for reporting to agencies or support of waste treatment decisions.
• Industrial and Laboratory Use: Provides guidance for plant operators, laboratory technicians, and environmental consultants involved in waste sampling and quality assurance.

By following this standard, personnel can avoid sampling errors-such as over-representation of a particular waste layer-and reduce risks associated with inadequate or biased sampling.

Related Standards

Implementing ASTM D5495-21 is most effective when used alongside other ASTM standards that provide detailed guidance for broader sampling and field procedures:

• ASTM D4687: Guide for General Planning of Waste Sampling-Covers plans, safety, QA, preservation, labeling, and chain-of-custody.
• ASTM D5088: Practice for Decontamination of Field Equipment Used at Waste Sites-Ensures that sample equipment does not introduce contamination.
• ASTM D5283: Practice for Environmental Field Operations-Detailed procedures for project management and field quality assurance.
• ASTM D5743: Practice for Drum Sampling-Addresses sampling in drums or similar multilayered containers.
• ASTM D6026: Practice for Significant Digits in Geotechnical Data-Guidelines for numerical data reporting.
• ASTM D5681: Terminology for Waste and Waste Management-Definitions for terms relevant to waste sampling and management.

Summary

ASTM D5495-21 plays a crucial role in the safe and accurate sampling of liquid wastes, providing a standardized method for environmental professionals, laboratories, and waste handlers. By following its prescribed procedures, organizations can ensure representative sampling for regulatory, safety, and environmental decision-making, while supporting broader waste management and compliance objectives.

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.
Designation: D5495 − 21
Standard Practice for
Sampling with a Composite Liquid Waste Sampler
(COLIWASA)
This standard is issued under the fixed designation D5495; 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.
1. Scope 2. Referenced Documents
1.1 This practice describes the procedure for sampling 2.1 ASTM Standards:
liquids with the composite liquid waste sampler, or “COLI- D4687 Guide for General Planning of Waste Sampling
WASA.” The COLIWASAis an appropriate device for obtain- D5088 Practice for Decontamination of Field Equipment
ing a representative sample from stratified or unstratified Used at Waste Sites
liquids. Its most common use is for sampling containerized D5283 Practice for Generation of Environmental Data Re-
liquids, such as tanks, barrels, and drums. It may also be used lated to Waste ManagementActivities: QualityAssurance
for pools and other open bodies of stagnant liquid. and Quality Control Planning and Implementation
D5681 Terminology for Waste and Waste Management
NOTE1—AlimitationoftheCOLIWASAisthatthestoppermechanism
D5743 Practice for Sampling Single or Multilayered
may not allow collection of approximately the bottom 2.54 cm (1 in.) of
Liquids, With or Without Solids, in Drums or Similar
material, depending on construction of the stopper.
Containers
1.2 The COLIWASA should not be used to sample flowing
D6026 Practice for Using Significant Digits in Geotechnical
or moving liquids.
Data
1.3 Units—The values stated in SI units are to be regarded
D6232 Guide for Selection of Sampling Equipment for
as standard. No other units of measurement are included in this
WasteandContaminatedMediaDataCollectionActivities
standard. All observed and calculated values shall conform to
the guidelines for significant digits and rounding established in 3. Terminology
Practice D6026. Reporting of test results in units other than SI
3.1 Definitions—For definitions of terms used in this
shall not be regarded as nonconformance with this standard.
standard, see Terminology D5681.
1.4 This standard does not purport to address all of the
4. Summary of Practice
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro-
4.1 A clean device is slowly lowered into the liquid to be
priate safety, health, and environmental practices and deter-
sampled.After it has filled, the bottom of the sampling tube is
mine the applicability of regulatory limitations prior to use.
closed and the device is retrieved. The contents are subse-
1.5 This international standard was developed in accor-
quently discharged into a sample container.
dance with internationally recognized principles on standard-
5. Significance and Use
ization established in the Decision on Principles for the
Development of International Standards, Guides and Recom-
5.1 Thispracticeisapplicabletosamplingliquidwastesand
mendations issued by the World Trade Organization Technical
other stratified liquids. The COLIWASA is used to obtain a
Barriers to Trade (TBT) Committee.
vertical column of liquid representing an accurate cross section
of the sampled material. To obtain a representative sample of
stratified liquids, the COLIWASAshould be open at both ends
This practice is under the jurisdiction of ASTM Committee D34 on Waste
Management and is the direct responsibility of Subcommittee D34.01.03 on
Sampling Equipment. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Current edition approved May 1, 2021. Published May 2021. Originally contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
approved in 1994. Last previous edition approved in 2016 as D5495 – 03 (2016). Standards volume information, refer to the standard’s Document Summary page on
DOI: 10.1520/D5495-21. the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D5495 − 21
3,4
so that material flows through it as it is slowly lowered to the COLIWASAis shown in Fig. 1 (deVera et al.); however, the
desired sampling depth. The COLIWASAmust not be lowered design can be modified or adapted, or both, to meet the needs
with the stopper in place. Opening the stopper after the tube is of the sampler. COLIWASAs must be selected that are con-
submerged will cause material to flow in from the bottom layer structed of materials compatible with the waste being sampled
only, resulting in gross over-representation of that layer. and with the analyses or tests to be performed. Due to the
unknown nature of most containerized liquid wastes, COLI-
5.2 This practice is to be used by personnel acquiring
WASAs made of glass or polytetrafluoroethylene are best for
samples.
general use.
5.3 This practice should be used in conjunction with Guide
D4687 which covers sampling plans, safety, QA, preservation,
7. Sample Containers
decontamination, labeling, and chain-of-custody procedures;
7.1 Plastic, glass, or other nonreactive containers should be
Practice D5088 which covers decontamination of field equip-
used. Refer to Guide D6232 for further information on con-
ment used at waste sites; Practice D5283 which covers project
tainers.
specifications and practices for environmental field operati
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: D5495 − 03 (Reapproved 2016) D5495 − 21
Standard Practice for
Sampling Withwith a Composite Liquid Waste Sampler
(COLIWASA)
This standard is issued under the fixed designation D5495; 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.
1. Scope
1.1 This practice describes the procedure for sampling liquids with the composite liquid waste sampler, or “COLIWASA.” The
COLIWASA is an appropriate device for obtaining a representative sample from stratified or unstratified liquids. Its most common
use is for sampling containerized liquids, such as tanks, barrels, and drums. It may also be used for pools and other open bodies
of stagnant liquid.
NOTE 1—A limitation of the COLIWASA is that the stopper mechanism may not allow collection of approximately the bottom inch 2.54 cm (1 in.) of
material, depending on construction of the stopper.
1.2 The COLIWASA should not be used to sample flowing or moving liquids.
1.3 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this
standard. All observed and calculated values shall conform to the guidelines for significant digits and rounding established in
Practice D6026. Reporting of test results in units other than SI shall not be regarded as nonconformance with this standard.
1.4 This standard does not purport to address all of the safety problems,concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appropriate safety safety, health, and healthenvironmental practices and
determine the applicability of regulatory limitations prior to use.
1.5 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.
2. Referenced Documents
2.1 ASTM Standards:
D4687 Guide for General Planning of Waste Sampling
D5088 Practice for Decontamination of Field Equipment Used at Waste Sites
D5283 Practice for Generation of Environmental Data Related to Waste Management Activities: Quality Assurance and Quality
Control Planning and Implementation
D5681 Terminology for Waste and Waste Management
D5743 Practice for Sampling Single or Multilayered Liquids, With or Without Solids, in Drums or Similar Containers
This practice is under the jurisdiction of ASTM Committee D34 on Waste Management and is the direct responsibility of Subcommittee D34.01.03 on Sampling
Equipment.
Current edition approved Sept. 1, 2016May 1, 2021. Published September 2016May 2021. Originally approved in 1994. Last previous edition approved in 20112016 as
D5495 – 03 (2011).(2016). DOI: 10.1520/D5495-03R16.10.1520/D5495-21.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D5495 − 21
D6026 Practice for Using Significant Digits in Geotechnical Data
D6232 Guide for Selection of Sampling Equipment for Waste and Contaminated Media Data Collection Activities
3. Terminology
3.1 Definitions—For definitions of terms used in this standard, see Terminology D5681.
4. Summary of Practice
4.1 A clean device is slowly lowered into the liquid to be sampled. After it has filled, the bottom of the sampling tube is closed
and the device is retrieved. The contents are subsequently discharged into a sample container.
5. Significance and Use
5.1 This practice is applicable to sampling liquid wastes and other stratified liquids. The COLIWASA is used to obtain a vertical
column of liquid representing an accurate cross-section cross section of the sampled material. To obtain a representative sample
of stratified liquids, the COLIWASA should be open at both ends so that material flows through it as it is slowly lowered to the
desired sampling depth. The COLIWASA must not be lowered with the stopper in place. Opening the stopper after the tube is
submerged will cause material to flow in from the bottom layer only, resulting in gross over-representation of that layer.
5.2 This practice is to be used by personnel acquiring samples.
5.3 This practice should be used in conjunction with Guide D4687 which covers sampling plans, safety, QA, preservation,
decontamination, labeling, and chain-of-custody procedures; Practice D5088 which covers decontamination of field equipment
used at waste sites; Practice D5283 which covers project specifications and practices for environmental field operations,operations;
and Practice D5743 which covers drum sampling.
6. Sampling Equipment
6.1 COLIWASAs are available commercially with different types of stoppers and locking mechanisms, but they all operate using
the same principle. They can also be constructed from materials such as polyvinylchloride (PVC), glass, metal, or polytetrafluo-
3,4
roethylene (PTFE). A traditional model of the COLIWASA is shown in Fig. 1 [de(de Vera et al.];al.); however, the design can
be modified or adapted, or both, to meet the needs of the sampler. COLIWASAs must be sele
...