ASTM D6698-12

Standard Test Method for On-Line Measurement of Turbidity Below 5 NTU in Water

SIGNIFICANCE AND USE
5.1 Turbidity is undesirable in drinking water, plant effluent waters, water for food and beverage processing, and for a large number of other water-dependent manufacturing processes. Removal of suspended matter is accomplished by coagulation, settling, and filtration. Measurement of turbidity provides a rapid means of process control to determine when, how, and to what extent the water must be treated to meet specifications.  
5.2 This test method is suitable for the on-line monitoring of turbidity such as that found in drinking water, process water, and high purity industrial waters.  
5.3 The instrumentation used must allow for the continuous on-line monitoring of a sample stream.Note 1—See 8.2 for discussion on signal spikes resulting from bubbles.  
5.4 When reporting the measured result, appropriate units should also be reported. The units are reflective of the technology used to generate the result, and if necessary, provide more adequate comparison to historical data sets.  
5.4.1 Table 1 describes technologies and reporting results. Those technologies listed are appropriate for the range of measurement prescribed in this test method are mentioned, though others may come available.
5.4.2 For a specific design that falls outside of the reporting ranges in Table 1, the turbidity should be reported in turbidity units (TU) with a subscripted wavelength value to characterize the light source that was used.
SCOPE
1.1 This test method is applicable to the on-line measurement of turbidity under 5 nephelometric turbidity units (NTU) in water.  
1.2 It is the user's responsibility to ensure the validity of this test method for waters of untested matrices.  
1.3 In this test method calibration standards are defined in NTU values, but other assigned turbidity units are assumed to be equivalent.  
1.4 This test method assigns traceable reporting units to the type of respective technology that was used to perform the measurement. Units are numerically equivalent with respect to the calibration standard. For example, a 1 NTU formazin standard is also equal to a 1 FNU (formazin nephelometric units) standard, a 1 FNRU (formazin nephelometric ratio units) standard, and so forth.  
1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.6 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 and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 31-May-2012
• ICS: 13.060.60 - Examination of physical properties of water
• Technical Committee: D19 - Water
• Drafting Committee: D19.03 - Sampling Water and Water-Formed Deposits, Analysis of Water for Power Generation and Process Use, On-Line Water Analysis, and Surveillance of Water

Relations

• Replaces: ASTM D6698-07 - Standard Test Method for On-Line Measurement of Turbidity Below 5 NTU in Water
• Effective Date: 01-Jun-2012
• Referred By: ASTM D7285-06(2017) - Standard Guide for Recordkeeping Microfiltration and Ultrafiltration Systems
• Effective Date: 01-Jun-2012
• Referred By: ASTM D4410-16 - Terminology for Fluvial Sediment
• Effective Date: 01-Jun-2012
• Referred By: ASTM D6908-06(2017) - Standard Practice for Integrity Testing of Water Filtration Membrane Systems
• Effective Date: 01-Jun-2012
• Referred By: ASTM D7726-11(2016)e1 - Standard Guide for The Use of Various Turbidimeter Technologies for Measurement of Turbidity in Water
• Effective Date: 01-Jun-2012
• Referred By: ASTM D7725-17 - Standard Test Method for the Continuous Measurement of Turbidity Above 1 Turbidity Unit (TU)
• Effective Date: 01-Jun-2012
• Referred By: ASTM E2635-22 - Standard Practice for Water Conservation in Buildings Through In-Situ Water Reclamation
• Effective Date: 01-Jun-2012
• Referred By: ASTM D4188-17 - Standard Practice for Performing Pressure In-Line Coagulation-Flocculation-Filtration Test in Water
• Effective Date: 01-Jun-2012

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: D6698 − 12
StandardTest Method for
1
On-Line Measurement of Turbidity Below 5 NTU in Water
This standard is issued under the fixed designation D6698; 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 D3864 Guide for On-Line Monitoring Systems for Water
Analysis
1.1 This test method is applicable to the on-line measure-
2.2 Other Standards:
ment of turbidity under 5 nephelometric turbidity units (NTU)
EPA 180.1 Methods for Chemical Analysis of Water and
in water.
3
Wastes, Turbidity
1.2 Itistheuser’sresponsibilitytoensurethevalidityofthis
4
GLI Method 2
test method for waters of untested matrices.
Hach Method 8195 Determination of Turbidity by Nephelo-
4
1.3 In this test method calibration standards are defined in
metry EMMC Format
5
NTU values, but other assigned turbidity units are assumed to
ISO 7027 Determination of Turbidity
6
be equivalent.
Standard Method 2130B
7
2.3 Other Documents:
1.4 This test method assigns traceable reporting units to the
U.S. Patent 4,283,143 Patterson, James A. 1981. Optical
type of respective technology that was used to perform the
Characterization of a Suspension. United States Patent
measurement. Units are numerically equivalent with respect to
4,283,143, filed November 19, 1979, and issued August
the calibration standard. For example, a 1 NTU formazin
11, 1981.
standard is also equal to a 1 FNU (formazin nephelometric
U.S. Patent 4,291,980 Patterson, James A. 1981. Styrene-
units)standard,a1FNRU(formazinnephelometricratiounits)
Divinylbenzene Copolymer and Method of Manufac-
standard, and so forth.
turer. United States Patent 4,291,980, filed August 14,
1.5 The values stated in SI units are to be regarded as
1978, and issued September 29, 1981.
standard. No other units of measurement are included in this
U.S. Patent 5,777,011 Sadar, Michael J. 1998. Stabilized
standard.
Formazin Composition. United States Patent 5,777,011,
1.6 This standard does not purport to address all of the
filed December 1, 1995, and issued July 7, 1998.
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro-
3. Terminology
priate safety and health practices and determine the applica-
3.1 Definitions—For definitions of terms used in this test
bility of regulatory limitations prior to use.
method, refer to Terminology D1129.
2. Referenced Documents
3.2 Definitions of Terms Specific to This Standard:
2
3.2.1 calibration turbidity standard, n—a turbidity standard
2.1 ASTM Standards:
that is traceable and equivalent to the reference turbidity
D1129 Terminology Relating to Water
standard to within statistical errors; calibration turbidity stan-
D1193 Specification for Reagent Water
dard include commercially prepared 4000 NTU formazin,
D2777 Practice for Determination of Precision and Bias of
stabilized formazin, and styrenedivinylbenzene (SDVB).
Applicable Test Methods of Committee D19 on Water
D3370 Practices for Sampling Water from Closed Conduits
3
Available from United States Environmental Protection Association (EPA),
1
This test method is under the jurisdiction of ASTM Committee D19 on Water Ariel Rios Bldg., 1200 Pennsylvania Ave., NW, Washington, DC 20460, http://
and is the direct responsibility of Subcommittee D19.03 on Sampling Water and www.epa.gov.
4
Water-Formed Deposits, Analysis of Water for Power Generation and Process Use, Available from Hach Company, P.O. Box 389, Loveland, CO, 80539-0389,
On-Line Water Analysis, and Surveillance of Water. http://www.hach.com.
5
Current edition approved June 1, 2012. Published August 2013. Originally Available from International Organization for Standardization (ISO), 1 rue de
approved in 2001. Last previous edition approved in 2007 as D6698 – 07. DOI: Varembé, Case postale 56, CH-1211, Geneva 20, Switzerland, http://www.iso.ch.
6
10.1520/D6698-12. Available from Standard Methods for the Examination of Water and
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or Wastewater, 21st Edition, American Public Health Association, Washington, DC,
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM 2005, http://www.standardmethods.org.
7
Standards volume information, refer to the standard’s Document Summary page on Available from AMCO Clear, P.O. Box 245, Powell, OH, 43065, http://
the ASTM website. www.amcoclear.com.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

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D6698 − 12
3.2.1.1 Discussion—These stan
...

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: D6698 − 07 D6698 − 12
Standard Test Method for
1
On-Line Measurement of Turbidity Below 5 NTU in Water
This standard is issued under the fixed designation D6698; 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 test method is applicable to the on-line measurement of turbidity under 5 nephelometric turbidity units (NTU) in water.
1.2 It is the user’s responsibility to ensure the validity of this test method for waters of untested matrices.
1.3 In this test method calibration standards are defined in NTU values, but other assigned turbidity units are assumed to be
equivalent.
1.4 This test method assigns traceable reporting units to the type of respective technology that was used to perform the
measurement. Units are numerically equivalent with respect to the calibration standard. For example, a 1 NTU formazin standard
is also equal to a 1FNU 1 FNU (formazin nephelometric units) standard, a 1 FNRU standard (formazin nephelometric ratio units)
standard, and so forth.
1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.6 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 and health practices and determine the applicability of regulatory
limitations prior to use.
2. Referenced Documents
2
2.1 ASTM Standards:
D1129 Terminology Relating to Water
D1193 Specification for Reagent Water
3
D1889 Test Method for Turbidity of Water (Withdrawn 2007)
D2777 Practice for Determination of Precision and Bias of Applicable Test Methods of Committee D19 on Water
D3370 Practices for Sampling Water from Closed Conduits
D3864 Guide for On-Line Monitoring Systems for Water Analysis
2.2 Other StandardsStandards:
3
EPA 180.1 Methods for Chemical Analysis of Water and Wastes, Turbidity
4
GLI Method 2
4
Hach Method 8195 Determination of Turbidity by Nephelometry EMMC Format
5
ISO 7027 Determination of Turbidity
6
Standard Method 2130B
7
2.3 Other DocumentsDocuments:
USU.S. Patent 4,283,143 4,283,143Patterson, James A. 1981. Optical Characterization of a Suspension. United States Patent
4,283,143, filed November 19, 1979, and issued August 11, 1981.
1
This test method is under the jurisdiction of ASTM Committee D19 on Water and is the direct responsibility of Subcommittee D19.03 on Sampling Water and
Water-Formed Deposits, Analysis of Water for Power Generation and Process Use, On-Line Water Analysis, and Surveillance of Water.
Current edition approved June 15, 2007June 1, 2012. Published July 2007August 2013. Originally approved in 2001. Last previous edition approved in 20012007 as
D6698 – 01.D6698 – 07. DOI: 10.1520/D6698-07.10.1520/D6698-12.
2
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.
3
Available from United States Environmental Protection Association (EPA), Ariel Rios Bldg., 1200 Pennsylvania Ave., NW, Washington, DC 20460, http://www.epa.gov.
4
Available from Hach Company, P.O. Box 389, Loveland, CO, 80539-0389, www.hach.com.http://www.hach.com.
5
Available from International Organization for Standardization (ISO), 1 rue de Varembé, Case postale 56, CH-1211, Geneva 20, Switzerland, http://www.iso.ch.
6
Available from Standard Methods for the Examination of Water and Wastewater, 21st Edition, American Public Health Association, Washington, DC, 2005,
www.standardmethods.org.http://www.standardmethods.org.
7
Available from AMCO Clear, P.O. Box 245, Powell, OH, 43065, www.amcoclear.com.http://www.amcoclear.com.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
D6698 − 12
USU.S. Patent 4,291,980 4,291,980Patterson, James A. 1981. Styrene-Divinylbenzene Copolymer and Method of Manufac-
turer. United States Patent 4,291,980, filed August 14, 1978, and issued September 29, 1981.
USU.S. Patent 5,777,011 5,777,011Sadar, Michael J. 1998. Stabilized Formazin Composition. United States Patent 5,777,011,
...