1. Methods for the Detection of Soluble Salts
William D. Corbett
KTA-Tator, Inc.
This one-hour webinar describes the various industry methods for detection of soluble salt contamination on steel surfaces.

2. Introduction Webinar Content: Webinar will not include:
Overview and Purpose of SSPC Guide 15
Listing of ISO Standards for Soluble Salt Detection
Methods of Surface Extraction
Methods of Analysis in the Shop or Field
Conversions Based on Assumption of Sodium Chloride
Webinar will not include:
Comprehensive step-by-step instructions
Procedures for the Boiling Extraction Method
Discussions regarding sampling location and frequency
Discussions regarding “acceptable” levels of surface chloride and/or conductivity

3. Learning Objectives/Outcomes
Completion of this webinar will enable the participant to:
Describe the purpose of SSPC Guide 15
List the ISO Standards for soluble salt detection
Describe the difference between extraction and analysis
Describe six methods of surface extraction
Describe seven methods of analysis of extracted samples
Calculate surface concentrations based on sample concentration, sample volume and extraction area
Convert conductivity to surface concentration based on an assumption of sodium chloride
There are eight learning outcomes or objectives for this webinar. Completing this webinar will enable you to:
Describe the purpose of SSPC’s Technology Guide 15

4. Purpose of SSPC Guide 15
SSPC Technology Guide 15, “Field Methods for Retrieval and Analysis of Soluble Salts on Steel and Other Nonporous Surfaces”
Latest edition is June 1, 2005 (over 5 years old)
Scope: Common field methods for retrieval and analysis of soluble salts
Guide’s intent is to assist the user in selecting procedures for retrieval and analysis (via advantages & limitations) of soluble salts. No acceptance levels are included.
Acceptance levels are determined by the specifier

5. ISO Standards
ISO 8502, “Preparation of steel substrates before application of paints and related products – Tests for the assessment of surface cleanliness.”
Part 2: Laboratory determination of chloride on cleaned surfaces (1992)
Part 5: Measurement of chloride on steel surfaces prepared for painting – ion detection tube method (1998)
Parts 6, 9, 10 and 12 on next slide

6. ISO Standards, continued
Part 6: extraction of soluble contaminants for analysis – The Bresle method (1995)
Part 9: Field Method for conductimetric determination of water-soluble salts (1998)
Part 10: Field method for the titrimetric determination of water-soluble chloride (1999)
Part 12: Field method for the titrimetric determination of water-soluble ferrous ions (2003)

7. Draft ASTM Standard
Draft 9 of Work Item 3049, “Standard Test Methods for Assessing the Concentration of Soluble Chlorides on Abrasive Blast Cleaned Metallic Surfaces”
Repeatability study scheduled for December 2010
Goal: Publish standard in 2011

8. Extraction versus Analysis
Two basic steps to determining soluble salt contamination:
Surface Extraction: The sampling of a known area for the purpose of determining the level of contamination
Analysis: The testing of the extracted sample for specific anions or conductivity

9. Methods of Extraction Webinar will describe: Swabbing Latex Sleeve
Latex Cell
Saturated Contact Pad
Magnetic Cell
Filter Paper Saturation
Notes: Other methods may exist but are not included
Some proprietary information/images used

10. Methods of Analysis Webinar will describe the use of:
Chloride ion test strips
Chloride ion detection tubes
Drop titration
Ferrous ion test strips
Nitrate ion test strips
Sulfate ion meter
Conductivity meters (non-ion specific)
Notes: Other methods may exist but are not included
Some proprietary information/images used

11. Extraction-Analysis Methods Compatibility Chart
Methods of Surface Extraction
Methods of Analysis
E1: Surface Swabbing
A1: Chloride Ion Test Strip
A2: Drop Titration
A3: Chloride Ion Detection Tube
A4: Probe-Type Conductivity Meter
E2: Adhesively Bonded Patch Cell
E3: Adhesively Bonded Sleeve

12. Surface Swabbing Procedure
Pre-packaged Test Kit
Demineralizer
Graduated cylinder
Two plastic beakers
Plastic ruler
Cotton balls
Tweezers
Chloride indicator strips
Ferrous ion indicator strips
pH paper

13. Surface Swabbing Procedure
Measure a known area on the surface to be tested (e.g., 15 cm x 15 cm, or 225 cm2)
Pour a measured volume of distilled or deionized water into a plastic beaker (e.g., 22.5 mL). Water may be purchased or demineralized on site

14. Surface Swabbing Procedure
3. Dampen a sterile cotton ball in the beaker of water and swab the measured area. Be certain to use tweezers or a chloride-free latex glove. Avoid drips from vertical surfaces.
4. Swirl the cotton ball in the beaker of water, then wring cotton against beaker wall.
5. Repeat the swabbing and rinsing procedure four more times. Use a new cotton ball each time.

15. Surface Swabbing Procedure
Dry the area using a clean cotton ball. Place all cotton balls in the beaker
Stir the cotton balls in the water for 2 minutes, then wring all and measure the final volume
Obtain a control sample using the same procedures, (eliminating surface swabbing). Cover & sit for 3 minutes

16. Analysis of Swabbing Extraction
Chloride Ion Test Strips
Ferrous Ion Test Strips
Alternative Methods (described later)
Conductivity
Chloride ion detection tubes

17. Analysis of Swabbing Extraction - Chloride Ion
Remove test strip from bottle
Immerse bottom of test strip in extraction solution
Solution wicks-up center orange column
Yellow string at top turns black when analysis is complete

18. Analysis of Swabbing Extraction - Chloride Ion
Peak of the white coloration in the center orange column indicates “Quantab Unit”
Convert Quantab Unit to PPM using conversion chart on bottle
Record batch no. from bottle

19. Calculating Surface Concentrations-Chloride (swab)
Entry
Result
PPM (from chart)
124 PPM
Quantity of water
22.5 mL
PPM x Quantity of Water
124 x 22.5 = 2790 µg
Area sampled
225 cm2
Micrograms ÷ Area Sampled
2790÷225 =12.4 µg/ cm2

20. Ferrous Ion Analysis Remove strip from bottle Dip strip in sample
Compare color to chart and record mg/L (PPM)
Convert PPM to µg/cm2 (PPM x mL of water)÷ area sampled

21. Latex Sleeve Procedure
Pre-packaged Test Kit
Five latex sleeves
Five pre-measured bottles of extraction liquid
Five chloride ion detection tubes
Tube breaker
Aspirator bulb
Instructions

22. Latex Sleeve Procedure
Pour entire contents of the premeasured extraction solution into the sleeve
Remove the pressure sensitive backing from the sleeve adhesive ring
Remove most of the air, then attach the sleeve to the surface

23. Latex Sleeve Procedure
Lift and hold the free end of the sleeve upright to allow the extraction solution to contact the surface
Use the other hand to massage the solution through the sleeve against the surface for a minimum of 2 minutes
Return the liquid into the sleeve and remove the sleeve from the surface

24. Analysis of Latex Sleeve Extraction
Chloride ion detection tube only
Pre-packaged kit
Chloride ion detection tubes
Nitrate ion detection strips
Sulfate ion detection meter
Alternative Methods (described earlier)
Chloride Ion Test Strips
Ferrous Ion Test Strips

25. Chloride Ion Detection Tube Analysis
Snap off both ends of the detection tube using the metal tube breaker
Immerse the end of the tube into the sleeve containing the extracted solution. The direction of travel is indicated by the arrow (upwards)
Use the aspirator bulb to assist with the tube saturation process as necessary

26. Chloride Ion Detection Tube Analysis
Capillary action of the tube is complete when the white cotton fibers at the top of the tube turn amber
The “pink” silver dichromate will precipitate white (silver chloride) in the presence of chloride
The pink/white intersection indicates PPM chloride (read from gradation on tube), as indicated by the red arrow
Typical range of measurement is 0+ to 60 PPM

27. Chloride, Nitrate & Sulfate Analysis
Pre-packaged Test Kit
Five extraction kits
Five chloride ion detection tubes
Five nitrate ion test strips
Five autovial filters and cone funnels
Five glass sample bottles
Five sulfate reagents (0.1g Barium Chloride)
One colorimeter for sulfate detection

28. Nitrate Analysis Remove the test strip from the protective packaging
Immerse the “pillow end” into the solution for 2 seconds.
After 1 minute, compare color on the pillow to the color chart provided

29. Sulfate Analysis
Remove the plunger from the autovial filter assembly. Pour extracted sample through the paper funnel into the filter
Replace the plunger and position the filter onto the empty extract bottle.
Depress the plunger and filter the solution
A minimum of 7 mL is required

30. Sulfate Analysis
Recap the bottle and remove fingerprints using the cloth
Insert the bottle into the colorimeter with the vertical index line on the bottle lined-up with the point of the triangle embossed on the meter
Close the lid and depress the “zero” until “bLA” is displayed

31. Sulfate Analysis
Remove the sample container from the meter and pour the contents of one of the sulfate reagent bottles into the solution
Cap the sample container and shake for 10 seconds. remove fingerprints using the cloth provided
10. Insert the bottle into the colorimeter (as described earlier) Close the lid and depress the “Read” button.

32. Sulfate Analysis
11. Re-insert the bottle into the colorimeter with the vertical index line on the bottle lined-up with the point of the triangle embossed on the meter 12. Close the lid and depress the “Read” button. The meter will display the sulfate concentration in PPM

33. Converting PPM to Surface Concentration (Latex Sleeve Method)
Opening of latex sleeve is 10 cm2
Premeasured extraction solution is 10 mL
Since area extracted and volume of test solution cancel out, there is no conversion required (shown below)
Entry
Result
PPM
25 PPM
PPM x mL of Solution
25 x 10 = 250 micrograms
Area Extracted
10 cm2
Micrograms ÷ Area
25 micrograms/cm2

34. Latex Patch/Cell Procedure
Adhesive patch/cell covered with a latex film forms a cavity once attached
Patch/cell is injected with an extraction solution using a hypodermic needle
Extracted solution is tested for anions or conductivity
Patch:
12.25 cm2
Cell:
12.5 cm2

35. Latex Patch/Cell Procedure
The label and foam cut-out is removed from the patch/cell
The latex patch/cell is attached to the surface
The air is extracted from the latex patch/cell using the 5 mL syringe 1 2 3 2 3

36. Latex Patch/Cell Procedure
An extraction liquid or demineralized water is used for the extraction
A known quantity of either is drawn into the 5 mL syringe (typically mL)
Note: Procedure may require use of extraction liquid

37. Latex Patch/Cell Procedure
The extraction liquid is injected into the latex patch/cell
The solution is massaged inside the patch/cell for seconds
Withdraw/re-inject/ massage a minimum of 3 more times
Withdraw and dispense sample for analysis

38. Latex Patch/Cell: Methods of Analysis
Chloride ion detection strips (described earlier)
Chloride ion detection tubes (described earlier)
Ferrous ion strips (described earlier)
Drop Titration
Conductivity

39. Latex Patch/Cell: Methods of Analysis
Drop Titration Kit Includes:
50 latex cells
Extraction fluid & waste collection bottle
Clear analysis vial
Syringes
Drop titration analysis kit
Instructions

40. Latex Patch/Cell: Methods of Analysis
Drop Titration
Kit contains 4 dropper bottles
Bottle 4 is a 5:1 dilution of Bottle 3
Procedure:
Bottle 1: add 2 drops; swirl
Bottle 2: add 2 drops; swirl (sample turns yellow)

41. Latex Patch/Cell: Methods of Analysis
Drop Titration, con’t.
Anticipate high chloride levels: Select Bottle 3
Anticipate low chloride levels: Select Bottle 4
Add single drops of selected bottle until sample turns blue
Record Bottle used & no. of drops added

42. Latex Patch/Cell: Methods of Analysis
No. of Drops – Bottle 3
Concentration of Chloride Ion 1
Less than 10 µg/cm2 2
µg/cm2 3
µg/cm2 4
µg/cm2
No. of Drops – Bottle 4
Concentration of Chloride Ion 1
Less than 2 µg/cm2 2
2 - 4 µg/cm2 3
4 - 6 µg/cm2 4
µg/cm2
Note: 1 µg/cm2 = 10 mg/m2

43. Latex Patch/Cell: Methods of Analysis
Conductivity Meter
Verify accuracy of conductivity meter
Measure conductivity of “blank”
Measure conductivity of sample
Deduct conductivity reading of “blank” from conductivity reading of sample

44. Direct Sampling and Analysis
Direct Sampling Kit
Digital conductivity meter
25 latex patches
6 beakers
200 mL distilled water
20 mL syringe
Direct sampling eliminates possible contamination by obtaining extraction liquid directly from the bottle of distilled water supplied with the kit without transfer to a container, and by applying the extracted sample directly onto the measuring cell of a conductivity meter.

45. Direct Sampling and Analysis
Direct Sampling Procedure
Measure conductivity of supplied distilled water (“blank”)
Extract sample using latex patch (previously described)
Measure conductivity of extracted sample
Deduct “blank” from conductivity value

46. Contact Pad Saturation: Extraction and Analysis
SaltSmart™
Extraction using pre-measured de-ionized water ampoule connected to sampling device
Analysis using conductivity meter

47. Take the SaltSmart ™ device out of the sealed package, taking care not to touch the sensor
Place the included ampoule containing pre-measured de-ionized water onto the SaltSmart ™ device
Use a strip of painters tape or other suitable no-residue tape to hold the sensor onto the surface under test
Wait approximately 8-10 minutes, then take the SaltSmart ™ device off the surface (don’t worry, you can’t get it wrong, the SaltSmart ™ meter will let you know)
Place the SaltSmart ™  device into the SaltSmart ™ meter, and read the value on the backlit display

48. Soluble Salt Meter (SSM)
Extraction and Analysis
Attach SSM to surface (magnetic)
Inject de-ionized water into measurement chamber (via 3 mL fixed volume dispenser)
Meter agitates solution
Value is displayed and stored
Wipe surface and flush meter

49. Soluble Salinity Meter (SSM)
Extraction and Analysis
Attach measurement cell to the surface (magnetic)
Inject 10 mL of de-ionized water using syringe. Press start key on meter
Activate the solution stirrer bar
Measurement is displayed and stored
Wipe surface and flush cell

50. Concentric Ring Conductivity Meter
Extraction using saturated filter paper; Analysis using conductivity
Saturate filter paper disc with 1.6 mL de-ionized water
Place saturated paper onto surface; push paper into surface texture using tweezers
Prepare salt contamination meter
Remove paper and position onto central area of the meter
Close lid, activate meter and read value from the display (µg/cm2)

51. Converting Conductivity to Surface Concentration
Appendix C.1 in SSPC Guide 15
Estimate of surface concentration
Assumption is sodium chloride
E = 0.3 x S x (V÷A)
E: Surface concentration (μg/cm2)
S: Conductivity (μS/cm)
V: Volume of extraction solution used
A: Area of sample collection

52. Summary During this webinar, we have:
Described the purpose of SSPC Guide 15
Listed the ISO Standards for soluble salt detection
Described the difference between extraction and analysis
Described six methods of surface extraction
Described seven methods of analysis of extracted samples
Calculated surface concentrations based on sample concentration, sample volume and extraction area
Converted conductivity to surface concentration based on an assumption of sodium chloride
In summary, we have

53. Methods for the Detection of Soluble Salts
THE END
Thank you for attending his one-hour webinar on methods for the detection of soluble salts.