Hanna Instruments HI 3812 User Manual

Hi 3812 hardness test kit, Instruction manual

S P E C I F I C A T I O N S

Instruction Manual

www.hannainst.com

Dear Customer,
Thank you for choosing a Hanna Product.
Please read the instructions carefully before using the chemical
test kit. It will provide you with the necessary information for
correct use of the kit.
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:

• Hardness Buffer, 1 bottle with dropper (30 mL);
• Calmagite Indicator, 1 bottle with dropper (10 mL);
• HI 3812-0 EDTA Solution, 1 bottle (120 mL);
• 1 plastic beaker (20 mL) with cap;
• 1 plastic beaker (50 mL) with cap;
• 1 syringe (1 mL) with tip.

Note: any damaged or defective item must be returned in its
original packing materials.

ISTR3812R5 01/07

HI 3812

Hardness Test Kit

In history, water hardness was defined by the capacity of
water to precipitate soap. The ionic species in the water
causing the precipitation was later found to be primarily
calcium and magnesium. In the present, therefore, water
hardness is actually a quantitative measure of these ions in
the water sample. It is also now known that certain other ion
species, such as iron, zinc and manganese, contribute to the
overall water hardness. 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, quick and safe. The compact size provides the versatility
to use the kit anywhere. The design of the kit makes it easy
to handle.

Range

0.0 to 30.0 mg/L (ppm) CaCO

0 to 300 mg/L (ppm) CaCO

Smallest Increment 0.3 mg/L [in the 0-30 mg/L range]

3 mg/L [in the 0-300 mg/L range]

Analysis Method

EDTA titration

Sample Size

5 mL or 50 mL

Number of Tests

100 (average)

Case Dimensions

200x120x60 mm (7.9x4.7x2.4")

Shipping Weight

460 g (1 lb.)

The hardness level as mg/L (ppm) calcium carbonate 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
LOOK AT THE BACK PAGE FOR THE ILLUSTRATED PROCEDURE

Note: push and twist pipet tip into tapered end of syringe
ensuring an air-tight fit.

HIGH RANGE – 0 to 300 mg/L CaCO

• Remove the cap from the small

plastic beaker. Rinse the plastic
beaker with the water sample,
fill to the 5 mL mark and replace
the cap.

• Add 5 drops of Hardness Buffer through the cap port

and mix carefully swirling the beaker 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.

Standard Methods for the Examination of Water and
Wastewater.
Annual Book of ASTM Standard, vol. 11.01, Water (I).

The chemicals contained in this kit may be hazardous if
improperly handled. Read the relevant Safety Data Sheet
before performing this test.

x 1

x 300 = CaCO

x 30 = CaCO

• Continue adding the titration solution

until the solution becomes purple, then
mix for 15 seconds after each additional
drop until the solution turns blue.

• Read off the milliliters of titration solution from the syringe

scale and multiply by 300 to obtain mg/L (ppm) CaCO

LOW RANGE – 0.0 to 30.0 mg/L CaCO

If result is lower than 30 mg/L, the precision of the test can
be improved by following the procedure below.

• Remove the cap from the large

plastic beaker. Rinse it with the
water sample, fill to the 50 mL
mark and replace the cap.

• Proceed with the titration as for the

high range test.

• Read off the milliliters of titration solution from the syringe

scale and multiply by 30 to obtain mg/L (ppm) CaCO

x 5

Chemical Reaction

Significance and Use

Specifications

Instructions

Safety Data Sheets

Accessories

HI 3812-100

replacement kit (100 tests average)

HI 740032P

cap for 20 ml plastic beaker (10 pcs)

HI 740034P

cap for 50 ml plastic beaker (10 pcs)

HI 740036P

50 ml plastic beaker (10 pcs)

HI 740037P

20 ml plastic beaker (10 pcs)

HI 740142P

1 ml graduated syringe (10 pcs)

HI 740144P

tips for 1 ml graduated syringe (10 pcs)

Bibliography

15”

• Take the titration syringe and

push the plunger completely into
the syringe. Insert tip into
HI 3812-0 EDTA Solution and
pull the plunger out until the
lower edge of the seal is on the
0 mL mark of the syringe.

• Place the syringe tip into the

cap port of the plastic beaker
and slowly add the titration
solution dropwise, swirling to
mix after each drop.