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SCAT®
Kit
Surface Contamination
Analysis Test Kit
Designed to Identify &
Quantify Water Soluble Chemical Contamination
 Overview
SCAT
Kit (Surface Contamination Analysis Test Kit) provides the necessary
equipment to analyze surfaces for the presence of chlorides, soluble
ferrous salts, and alkaline/acidic contaminants.
The protective coatings industry is
recognizing the role of these "unseen" contaminants in causing
premature corrosion and untimely coating failures such as undercutting,
metallic corrosion, accelerated degradation of paints, and blistering
and premature failure of coatings and linings in immersion service.
SCAT Kit is simple to use and offers the
convenience of field portability, while providing the reliability of
laboratory analysis. The kit contains a graduated cylinder, beakers,
tweezers, water demineralizer, cotton swabs, chloride ion titrator
indicator strips, ferrous ion indicator strips, pH paper, ruler and
instructions. All items are packaged in a lightweight rugged durable
carrying case.
SCAT Kit (Surface Contamination Analysis
Test Kit) provides the necessary equipment to conduct analyses of
surfaces for the presence of chlorides, soluble ferrous salts, and
alkaline/acidic contaminants.
Evaluation of Chloride
and Ferrous Ion Results
The charts on the test strips give the
concentration of chloride and ferrous ion as parts per million (ppm)
which, for aqueous solutions, is the same as micrograms/milliliter
(µg/ml). Therefore, the actual amount of ion extracted is obtained by
multiplying the ppm by the volume of water used. For example, if 10 ml
of water was used, and the Quantab read 62 ppm, then 620 µg of chloride
were extracted. A microgram (µg) is one millionth of a gram; 454 grams
equals 1 lb.
By knowing the area swabbed the
concentration can now be determined by simple division. If, for example,
in the above case, a 6 cm x 9 cm (54 cm2) area was used the
chloride concentration is 620 micrograms/54cm2= 11.5
micrograms/cm2. Furthermore, this can be convened to
milligrams/meter2 by multiplying by 10. (11.5 µg/ cm2
x 10 = 115 mg/m2).
If a 6 " x 6" area (15 cm x 15
cm) and 22.5 ml of water are used, the concentrations determined in ppm
are identical to milligrams/meter2, with no further
calculations needed.
pH
pH is determined with the pH paper
included in the kit. The pH can be determined on the water extract
obtained in the above section by dipping the strip into the extract and
comparing the resulting color with that on the color scale included with
the paper. Alternately, the pH of the steel surface itself can be
determined by placing a small strip of the paper on the surface (e.g.,
1-1/2 ") and moistening it with 1 or 2 drops of deionized water,
making sure that the pH paper is in intimate contact with the steel
surface. Again, compare the resulting color with the color chart. It is
always a good practice to check the pH of the water used, since this may
or may not be 7 (neutral).
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Technical Data
- Chloride Detection Limit:
approximately 40 PPM
- Ferrous Ion Detection Limit:
approximately 3 PPM
- Demineralizer Cartridge Life: good for
approximately 3000 ml of water
- pH Paper Range: 4 - 9, verified by
color scale
Scat Kit Contents
-
 Graduated
Cylinder
- Beakers
- Tweezers
- Water Demineralizer
- Cotton Balls
- Chloride Ion Titrator Indicators
- Ferrous Ion Indicators
- pH Paper (range 4 - 9)
- Ruler
- Instructions
- Carrying Case
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| Operating Procedures
- Use a ruler and chalk or pencil to
measure out a convenient area, in centimeters (cm), on the surface to
be tested. A 10 cm x 10 cm (100 cm2) area has been found to
be convenient, but other sizes will do. (1 inch = 2.54 cm).
- Use only distilled or deionized water to
perform the test. The portable demineralizer included in the SCAT Kit
is a convenient way of obtaining this water. Simply pour tap water
into the plastic bottle, attach the demineralizer cartridge in the
direction indicated, invert, and squeeze out the desired amount of
water. The cartridge can be used until the blue color turns brown, as
indicated on the side of the cartridge. Once this occurs, discard the
cartridge and replace. Each cartridge should be good for approximately
3000 ml of water.
- Using the graduated cylinder, measure
out an exact volume of deionized water into one of the small plastic
beakers. At least 10 ml will be required.
- Dampen one of the cotton balls in the
beaker of water and thoroughly swab the measured area, using the
tweezers. After swabbing, swirl the cotton ball in the water and
squeeze it against the side of the beaker each time. Repeat this
procedure at least 4 times, then place the cotton ball in the beaker
of water. Use a fresh cotton ball to dry off the test area, and place
it in the beaker as well.
- Stir or swirl the contents of the beaker
containing the water and cotton balls for at least 2 minutes to assure
thorough mixing.
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 Determine the chloride level by placing
the lower end of one of the Quantab test strips in the water in the
beaker.
- Allow the water to wick up and saturate
the test strip. Saturation is achieved 2 minutes after the yellow
strip across the top of the column begins to turn dark blue. This
takes about 20 minutes.
- The presence of chlorides is indicated
by a color change of the tan scale to white. Note the scale number at
the top edge of the white, and compare it to the calibration chart
enclosed with each Quantab bottle to obtain the concentration of
chloride.
- Ferrous ion can be determined on this
same extract by using the Ferrous Ion Test Strips. Simply moisten a
test strip in the extract and compare the color change to the
color-coded chart on the container label.
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