ASTM D6855-12

Standard Test Method for Determination of Turbidity Below 5 NTU in Static Mode

SIGNIFICANCE AND USE
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 is often accomplished by coagulation, settling, and filtration. Measurement of turbidity provides a rapid means of process control for when, how, and to what extent the water must be treated to meet specifications.
This test method is suitable to turbidity such as that found in drinking water, process water, and high purity industrial water.
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.
Table 1 describes technologies and reporting results (see also Refs (1),(2),(3)). Those technologies listed are appropriate for the range of measurement prescribed in this method. Others may come available in the future. Fig. X5.1 provides a flow chart to aid in selection of the appropriate technology for low-level static turbidity applications.
If a design that falls outside of the criteria listed in Table 1 is used, the turbidity should be reported in turbidity units (TU) with a subscripted wavelength value to characterize the light source that was used.
TABLE 1 Applicable Technologies Available for Performing Static Turbidity Measurements Below 5 NTU  Design and
Reporting Unit Prominent ApplicationKey Design FeaturesTypical Instrument RangeSuggested Application Nephelometric
non-ratio (NTU)White light turbidimeters. Comply
with USEPA Method 180.1 (1)
for low level turbidity monitoring.Detector centered at 90° relative
to the incident light beam. Uses
a white light spectral source.0.020 to 40Regulatory reporting
of clean water  Ratio White Light
turbidimeters (NTRU)Complies with ISWTR regulations and
Standard Method 2130B. (2)
Can be used for both
low and high level
measurement.Used a w...
SCOPE
1.1 This test method covers the static determination of turbidity in water (see 4.1).
1.2 This test method is applicable to the measurement of turbidities under 5.0 nephelometric turbidity units (NTU).
1.3 This test method was tested on municipal drinking water, ultra-pure water and low turbidity samples. It is the user's responsibility to ensure the validity of this test method for waters of untested matrices.
1.4 This test method uses calibration standards are defined in NTU values, but other assigned turbidity units are assumed to be equivalent.
1.5 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 1.0 NTU formazin standard is also equal to a 1.0 FNU standard, a 1.0 FNRU standard and so forth.
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. Refer to the MSDSs for all chemicals used in this procedure.

General Information

• Status: Historical
• Publication Date: 31-May-2012
• ICS: 19.100 - Non-destructive testing
• Technical Committee: D19 - Water
• Drafting Committee: D19.07 - Sediments, Geomorphology, and Open-Channel Flow

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: D6855 − 12
Standard Test Method for
1
Determination of Turbidity Below 5 NTU in Static Mode
This standard is issued under the fixed designation D6855; 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* D2777 Practice for Determination of Precision and Bias of
Applicable Test Methods of Committee D19 on Water
1.1 This test method covers the static determination of
D3370 Practices for Sampling Water from Closed Conduits
turbidity in water (see 4.1).
D5847 Practice for Writing Quality Control Specifications
1.2 This test method is applicable to the measurement of
for Standard Test Methods for Water Analysis
turbidities under 5.0 nephelometric turbidity units (NTU).
E691 Practice for Conducting an Interlaboratory Study to
1.3 This test method was tested on municipal drinking Determine the Precision of a Test Method
water, ultra-pure water and low turbidity samples. It is the
2.2 Other Referenced Standards:
user’s responsibility to ensure the validity of this test method
USEPA Method 180.1 Methods for Chemical Analysis of
4
for waters of untested matrices.
Water and Wastes, Turbidity
ISO 7027 (The International Organization for Standardiza-
1.4 This test method uses calibration standards are defined
5
tion) Water Quality—for the Determination of Turbidity
in NTU values, but other assigned turbidity units are assumed
to be equivalent.
3. Terminology
1.5 This test method assigns traceable reporting units to the
3.1 Definitions—For definitions of terms used in this
type of respective technology that was used to perform the
method refer to Terminology D1129.
measurement. Units are numerically equivalent with respect to
the calibration standard. For example, a 1.0 NTU formazin
3.2 Definitions:
standard is also equal to a 1.0 FNU standard, a 1.0 FNRU 3.2.1 calibration turbidity standard, n—Aturbiditystandard
standard and so forth.
that is traceable and equivalent to the reference turbidity
standard to within statistical errors; calibration turbidity stan-
1.6 This standard does not purport to address all of the
dards include commercially prepared 4000 NTU Formazin,
safety concerns, if any, associated with its use. It is the
stabilized formazin (see 9.2.3), and styrenedivinylbenzene
responsibility of the user of this standard to establish appro-
(SDVB) (see 9.2.4).
priate safety and health practices and determine the applica-
3.2.1.1 Discussion—these standards may be used to cali-
bility of regulatory limitations prior to use. Refer to the
brate the instrument.
MSDSs for all chemicals used in this procedure.
NOTE 1—Calibration standards may be instrument specific.
2. Referenced Documents
3.2.2 calibration verification standards, n—Defined stan-
2
2.1 ASTM Standards:
dards used to verify the accuracy of a calibration in the
D1129 Terminology Relating to Water
measurement range of interest.
D1192 Guide for Equipment for Sampling Water and Steam
3.2.2.1 Discussion—these standards may not be used to
3
in Closed Conduits (Withdrawn 2003)
perform calibrations, only calibration verifications. Included
D1193 Specification for Reagent Water
standards are opto-mechanical light scatter devices, gel-like
standards, or any other type of stable liquid standard.
1
This test method is under the jurisdiction of ASTM Committee D19 on Water
NOTE 2—Calibration verification standards may be instrument specific.
and is the direct responsibility of Subcommittee D19.07 on Sediments,
3.2.3 nephelometric turbidity measurement, n—The mea-
Geomorphology, and Open-Channel Flow.
Current edition approved June 1, 2012. Published June 2012. Originally surement of light scatter from a sample in a direction that is at
approved in 2003. Last previous edition approved in 2010 as D6855 – 10. DOI:
90° with respect to the centerline of the incident light path.
10.1520/D6855-12.
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
4
Standards volume information, refer to the standard’s Document Summary page on Available from United States Environmental Protection Association (EPA),
the ASTM website. Ariel Rios Bldg., 1200 Pennsylvania Ave., NW, Washington, DC 20460.
3 5
The last approved version of this historical standard is referenced on Available fromAmerican National Standards Institute (ANSI), 25 W. 43rd St.,
www.astm.org. 4th Floor, New York, NY 10036.
*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

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...

This document is not anASTM standard and is intended only to provide the user of anASTM 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:D6855–10 Designation: D6855 – 12
Standard Test Method for
1
Determination of Turbidity Below 5 NTU in Static Mode
This standard is issued under the fixed designation D6855; 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 (ϵ) indicates an editorial change since the last revision or reapproval.
1. Scope*
1.1 This test method covers the static determination of turbidity in water (see 4.1).
1.2 This test method is applicable to the measurement of turbidities under 5.0 nephelometric turbidity units (NTU).
1.3 This test method was tested on municipal drinking water, ultra-pure water and low turbidity samples. It is the user’s
responsibility to ensure the validity of this test method for waters of untested matrices.
1.4 This test method uses calibration standards are defined in NTU values, but other assigned turbidity units are assumed to be
equivalent.
1.5 This test method assigns traceable reporting units to the type of respective technology that was used to perform the
measurement.Unitsarenumericallyequivalentwithrespecttothecalibrationstandard.Forexample,a1.0NTUformazinstandard
is also equal to a 1.0 FNU standard, a 1.0 FNRU standard and so forth.
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. Refer to the MSDSs for all chemicals used in this procedure.
2. Referenced Documents
2
2.1 ASTM Standards:
D1129 Terminology Relating to Water
D1192 Guide for Equipment for Sampling Water and Steam in Closed Conduits
D1193 Specification for Reagent Water
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
D5847 Practice for Writing Quality Control Specifications for Standard Test Methods for Water Analysis
E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
2.2 Other Referenced Standards:
3
USEPA Method 180.1 Methods for Chemical Analysis of Water and Wastes, Turbidity
4
ISO 7027 (The International Organization for Standardization) Water Quality—for the Determination of Turbidity
3. Terminology
3.1 Definitions—For definitions of terms used in this method refer to Terminology D1129.
3.2 Definitions:
3.2.1 calibration turbidity standard, n—a—A turbidity standard that is traceable and equivalent to the reference turbidity
standard to within statistical errors, includingerrors; calibration turbidity standards include commercially prepared 4000 NTU
Formazin, stabilized formazin (see 9.2.3), and styrenedivinylbenzene (SDVB) (see 9.2.4). These
3.2.1.1 Discussion—these standards may be used to calibrate the instrument.
NOTE 1—Calibration standards may be instrument specific.
3.2.2 calibration verification standards, n—defined—Defined standards used to verify the accuracy of a calibration in the
measurement range of interest. These
1
This test method is under the jurisdiction of ASTM Committee D19 on Water and is the direct responsibility of Subcommittee D19.07 on Sediments, Geomorphology,
and Open-Channel Flow.
Current edition approved June 15, 2010.1, 2012. Published August 2010.June 2012. Originally approved in 2003. Last previous edition approved in 20032010 as
D6855 – 103. DOI: 10.1520/D6855-102.
2
For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM 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.
4
Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036.
*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

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D6855 – 12
3.2.2.1 Discussion—these standards may not be used to perform calibrations, only calibration verifications. Included standards
are opto-mechanical light scatter devices, gel-like standards, or any
...