Hach DR2400 - Page 711

DR/2400
Silica
Silica_PP_Low_HTB_Eng_Ody.fm Page 1 of 4
• The four-minute reaction time in step 4 is for samples at 20 °C; for samples at 10 °C, wait eight minutes;
for samples at 30 °C, wait two minutes.
• The one-minute reaction time in step 6 is for samples at 20 °C; for samples at 10 °C, wait two minutes;
for samples at 30 °C, wait 30 seconds.
• If testing for very low levels of silica, use Method 8282.
Silica
Method 8186
Heteropoly Blue Method*
*Adapted from Standard Methods for the Examination of Water and Wastewater.
Powder Pillows
LR (0.01 to 1.60 mg/L as SiO
2
)
Scope and Application: For water and seawater
1. Touch
Hach Programs.
Select program
651 Silica LR.
Touch
Start.
2. Fill two sample cells
with 10 mL of sample.
3. Add 14 drops of
Molybdate 3 Reagent to
each sample cell. Swirl to
mix.
4. Touch the timer icon.
Touch
OK.
A four-minute reaction
period will begin.
Tips and Techniques
Powder Pillows Method 8186
Hach Programs
10 mL 10 mL