ASTM D4940-15

Standard Test Method for Conductimetric Analysis of Water Soluble Ionic Contamination of Blast Cleaning Abrasives

SIGNIFICANCE AND USE
4.1 Abrasive media may contain ionic contamination naturally (for example, beach sand), from manufacturing (quenching with contaminated water), transportation, storage or use (in the case of abrasive that is reused). Ionic contamination on the abrasive may transfer to the surface during abrasive blast cleaning, resulting in potential osmotic blistering, accelerated underfilm corrosion and premature coating failure.  
4.2 This test method describes a shop/field procedure for assessing the level of conductive species on an abrasive.  
4.3 Abrasive standards published by SSPC (AB) and ISO 11126 provide tolerance levels for water soluble contaminants of the abrasive.
SCOPE
1.1 This test method describes a procedure for assessing blast cleaning abrasives for the presence of conductive-potential, ionic contaminants by determining the total concentration of water soluble conductive species using a conductivity test.  
1.2 This test method does not identify the ionic species present nor provide quantitative results on each species.  
1.3 This test method is based on a volume comparison among abrasives of similar sizes. A volume comparison is more closely related to surface area of the abrasives than is a weight comparison.  
1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.5 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: 30-Nov-2015
• ICS: 25.220.10 - Surface preparation
• Technical Committee: D01 - Paint and Related Coatings, Materials, and Applications
• Drafting Committee: D01.46 - Industrial Protective Coatings

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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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:D4940 −15
StandardTest Method for
Conductimetric Analysis of Water Soluble Ionic
1
Contamination of Blast Cleaning Abrasives
This standard is issued under the fixed designation D4940; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope Non-Metallic Blast CleaningAbrasives - Part 6: Determi-
nation of Water-Soluble Contaminants by Conductivity
1.1 This test method describes a procedure for assessing
3
Measurement
blast cleaning abrasives for the presence of conductive-
4
2.3 SSPC: The Society for Protective Coatings:
potential, ionic contaminants by determining the total concen-
SSPC-AB 1Mineral and Slag Abrasives
trationofwatersolubleconductivespeciesusingaconductivity
SSPC-AB 2Cleanliness of Recycled Ferrous MetallicAbra-
test.
sive
1.2 This test method does not identify the ionic species
SSPC-AB 3Ferrous Metallic Abrasive
present nor provide quantitative results on each species.
SSPC-AB 4Recyclable Encapsulated Abrasive Media
1.3 This test method is based on a volume comparison
3. Summary of Test Method
among abrasives of similar sizes. A volume comparison is
3.1 Abrasive and pure water are combined into a slurry that
more closely related to surface area of the abrasives than is a
is stirred to leach the soluble salts from the abrasive. This
weight comparison.
slurry is filtered and conductance of the filtrate is measured.
1.4 The values stated in SI units are to be regarded as
The conductivity, which is related to the concentration of
standard. No other units of measurement are included in this
soluble ionic materials contaminating the abrasive, is calcu-
standard.
lated from the conductance and the cell constant.
1.5 This standard does not purport to address all of the
4. Significance and Use
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro- 4.1 Abrasive media may contain ionic contamination natu-
priate safety and health practices and determine the applica-
rally (for example, beach sand), from manufacturing (quench-
bility of regulatory limitations prior to use. ingwithcontaminatedwater),transportation,storageoruse(in
the case of abrasive that is reused). Ionic contamination on the
2. Referenced Documents
abrasive may transfer to the surface during abrasive blast
2
cleaning, resulting in potential osmotic blistering, accelerated
2.1 ASTM Standards:
underfilm corrosion and premature coating failure.
D1193Specification for Reagent Water
E832Specification for Laboratory Filter Papers
4.2 This test method describes a shop/field procedure for
2.2 Other Standard:
assessing the level of conductive species on an abrasive.
ISO 11127-6Preparation of Steel Substrates beforeApplica-
4.3 Abrasive standards published by SSPC (AB) and ISO
tion of Paints and Related Products - Test Methods for
11126 provide tolerance levels for water soluble contaminants
of the abrasive.
1
This test method is under the jurisdiction of ASTM Committee D01 on Paint
5. Apparatus
and Related Coatings, Materials, andApplications and is the direct responsibility of
Subcommittee D01.46 on Industrial Protective Coatings.
5.1 Conductivity Bridge and Cell—Any commercial con-
Current edition approved Dec. 1, 2015. Published December 2015. Originally
ductivity bridge and conductivity cell typically having a range
approved in 1989. Last previous edition approved in 2010 as D4940– 10. DOI:
10.1520/D4940-15.
2 3
For referenced ASTM standards, visit the ASTM website, www.astm.org, or Available fromAmerican National Standards Institute (ANSI), 25 W. 43rd St.,
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM 4th Floor, New York, NY 10036, http://www.ansi.org.
4
Standards volume information, refer to the standard’s Document Summary page on Available from Society for Protective Coatings (SSPC), 40 24th St., 6th Floor,
the ASTM website. Pittsburgh, PA 15222-4656, http://www.sspc.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
D4940−15
of at least 5 µmho/cm to 10,000 µmho/cm with built-in 6.3 Potassium Chloride (KCl or 0.02 N KCl solution).
temperature compensation is satisfactory. A dip-type, pipet-
7. Sampling
type, or cup-type cell may be used.
7.1 Sampling shall be as follows unless otherwise agreed
5.2 Filter Paper, conforming to Specification E832,Type 1,
upon between the purchaser and the seller. Take two 1-L
Class C, to keep silt from fouling the surfaces of the conduc-
samples of abrasive at random from
...

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: D4940 − 10 D4940 − 15
Standard Test Method for
Conductimetric Analysis of Water Soluble Ionic
1
Contamination of Blasting Blast Cleaning Abrasives
This standard is issued under the fixed designation D4940; 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 describes a procedure for rapid evaluation ofassessing blast cleaning abrasives for the presence of
conductive-potential, ionic contaminationcontaminants by determining the total concentration of water soluble ionic contaminants
by means of conductive species using a conductivity test.
1.2 This test method does not identify the ionic species present nor provide quantitative results on each species.
1.3 This test method is based on a volume comparison among abrasives of similar sizes. A volume comparison is more closely
related to surface area of the abrasives than is a weight comparison.
1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.5 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:
D1193 Specification for Reagent Water
E832 Specification for Laboratory Filter Papers
2.2 Other Standard:
ISO 11127-6 Preparation of Steel Substrates before Application of Paints and Related Products - Test Methods for Non-Metallic
3
Blast Cleaning Abrasives - Part 6: Determination of Water-Soluble Contaminants by Conductivity Measurement
4
2.3 SSPC: The Society for Protective CoatingsCoatings:
SSPC-AB 1 Specification for Mineral and Slag Abrasives
SSPC-AB 2 Cleanliness of Recycled Ferrous Metallic Abrasive
SSPC-AB 3 Ferrous Metallic Abrasive
SSPC-AB 4 Recyclable Encapsulated Abrasive Media
3. Summary of Test Method
3.1 Abrasive and pure water are combined into a slurry that is stirred to leach the soluble salts from the abrasive. This slurry
is filtered and conductance of the filtrate is measured. The conductivity, which is related to the concentration of soluble ionic
materials contaminating the abrasive surface, abrasive, is calculated from the conductance and the cell constant.
4. Significance and Use
4.1 By-product abrasives manufactured from slags that are air cooled or quenched with pure water, normally contain low
concentrations of ionic materials, as do mined mineral abrasives. However, slags quenched with seawater or other contaminated
water, contain high amounts of ionic material as does seashore sand. This contamination of the abrasive canAbrasive media may
1
This test method is under the jurisdiction of ASTM Committee D01 on Paint and Related Coatings, Materials, and Applications and is the direct responsibility of
Subcommittee D01.46 on Industrial Protective Coatings.
Current edition approved June 1, 2010Dec. 1, 2015. Published June 2010December 2015. Originally approved in 1989. Last previous edition approved in 20032010 as
D4940 - 98 (2003).D4940 – 10. DOI: 10.1520/D4940-10.10.1520/D4940-15.
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 American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http://www.ansi.org.
4
Available from Society for Protective Coatings (SSPC), 40 24th St., 6th Floor, Pittsburgh, PA 15222-4656, http://www.sspc.org.http://www.sspc.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
D4940 − 15
contain ionic contamination naturally (for example, beach sand), from manufacturing (quenching with contaminated water),
transportation, storage or use (in the case of abrasive that is reused). Ionic contamination on the abrasive may transfer to the steel
surfaces being blasted, where it may accelerate corrosion. This test is useful in establishing the cleanliness of the abrasive at the
jobsite. surface
...