HI 38033
Total Hardness
0-30 gpg range
Test Kit
Instruction Manual
ISTR38033R2 02/07
Water hardness has traditionally been defined as the capacity
of water to precipitate soap. The ionic species in water
causing the precipitation were later found to be primarily
calcium and magnesium. At the present time, water hardness
is a quantitative measure of these ions in the water sample.
Now it is also known that certain other ion species, such as
iron, zinc and manganese, contribute to the overall hardness
of water. The measure and subsequent control of water
hardness is essential to prevent scaling and clogging in water
pipes. The Hanna hardness test kit makes monitoring easy
and quick. The compact size provides the versatility to use the
kit anywhere and the design makes the kit easy to handle.
Note:
1 gpg (grains per gallon) CaCO
3
is equivalent to 17
ppm CaCO
3
(where
ppm - parts per million - is
equivalent to mg/L).
Range
0 to 30 gpg CaCO
3
Smallest Increment
1 gpg CaCO
3
Analysis Method
EDTA titration
Sample Size
10 mL
Number of Tests
100
Case Dimensions
235x175x115 mm (9.2x6.9x4.5")
Shipping Weight
457 g (16.1 oz)
The hardness level as gpg calcium carbonate (CaCO
3
) is
determined by an EDTA (ethylene-diamine-tetraacetic acid)
titration. The solution is first adjusted to a pH of 10 using a
buffer solution. The indicator chelates with metal ions such as
magnesium or calcium to form a red colored complex. As EDTA
is added, metal ions complex with it. After all the free metal
ions have been complexed, an excess EDTA removes the metal
ions complexed with the indicator to form a blue colored
solution. This color change from red to blue is the endpoint of
the titration.
READ ALL THE INSTRUCTIONS BEFORE USING THE TEST KIT
• Remove the cap from the plastic vessel. Rinse the plastic
vessel with the water sample, fill to the 10 mL mark and
replace the cap.
• Add 5 drops of Buffer Solution through the cap port and
mix carefully by swirling the vessel in tight circles.
• Add 1 drop of Calmagite Indicator through the cap port
and mix as described above. The solution becomes a red-
violet color.
• Fill the plastic pipette with HI 38033-0 EDTA Solution
and insert the tip into the cap port of the plastic vessel.
Add the solution drop by drop, swirling to mix after
each drop, while keeping an accurate count of the number
of drops being added to the solution in the vessel.
Standard Methods for the Examination of Water and
Wastewater
, 20
th
Edition, 1998.
1987 Annual Book of ASTM Standard
, vol. 11.01 Water (1).
Dear Customer,
Thank you for choosing a Hanna Product.
Please read the instruction sheet carefully before using the
test kit. It will provide you with the necessary information for
correct use of the kit. If you need additional information, do
not hesitate to e-mail us at [email protected].
Remove the chemical test kit from the packing material and
examine it carefully to make sure that no damage has
occurred during shipping. If there is any noticeable damage,
notify your Dealer or the nearest Hanna office immediately.
Each kit is supplied with:
• Buffer Solution pH 10.2±0.2, 1 bottle with dropper
(30 mL);
• Calmagite Indicator, 1 bottle with dropper (10 mL);
• HI 38033-0 EDTA Solution, 2 bottles (2x75 mL);
• 1 plastic beaker (20 mL) with cap;
• 1 plastic pipette (1 mL).
Note:
Any damaged or defective item must be returned in its
original packing materials.
• Continue adding titration solution until the solution in
the plastic vessel becomes purple. Then mix for 15 seconds
after each additional drop until the solution turns blue.
• Record the number of drops needed to obtain the final
color change as gpg CaCO
3
of total hardness of your
sample.
drops of titrant = gpg CaCO
3
x 5
x 5
x 5
x 5
x 5
x 1
x 1
x 1
x 1
x 1
www.hannainst.com
Specifications
Significance and use
Chemical Reaction
Instructions
References
The chemicals contained in this kit may be hazardous if
improperly handled. Read the relevant Safety Data Sheet
before performing this test.
Safety Data Sheets
Accessories
HI 38033-100
Replacement kit (100 tests)
HI 740032P
cap for 20 ml plastic beaker (10 pcs)
HI 740037P
20 ml plastic beaker (10 pcs)
