Microsoft Word - WaterChemistry

119

Sample Containers and Preservation Techniques

Methods used by the laboratory usually specify what type of container and how much sample is

required to run an analysis. The following table provides a summary of the sample handling and

preservation requirements for some of the most common tests.

Parameter Bottle

Type

Minimum

Sample Containers..................................

Size

Maximum

Holding Time

Storage &

Preservation

Acidity P or GB 100ml 24 hrs/14 days refrigerate

Alkalinity P or G 200ml 24 hrs/14 days refrigerate

BOD (5 day) P or G 1L 6 hrs/48 hrs refrigerate

Boron P 100ml 28 days/6

months

Chloride P or G 250ml 28 days

Chlorine, residual P or G 500ml 0.5 hr/stat analyze on site

ASAP

COD P or G 500ml 28 days/28

days

analyze on site

ASAP

Color P or G 500ml 48 hrs/48 hrs refrigerate

Coliform, Total P or G 125ml 30 hrs refrigerate

Conductivity P or G 500ml 48 hrs/48 hrs refrigerate

Cyanide, Total P or G 500ml 28 days/28

days

add NaOH to

pH>12

refrigerate in dark

Fluoride P 300ml 28days/ 28

days

Hardness P or G 100ml 6 months/6

months

add HNO 3 to pH<2

Metals, general PA or GA 250ml 6 months/6

months

add HNO 3 to pH<2

Furnace PA or GA 250ml 6 months/6

months

Flame PA or GA 250ml 6 months/6

months

Mercury PA or GA 500ml 28 days/28

days

add HNO 3 to pH<2

Nitrogen

Ammonia

P or G 500ml 7 days/ 28

days

ASAP or add

H 2 SO 4 to pH<2 &

refrigerate

Nitrate P or G 100ml 48 hrs/48 hrs ASAP &

refrigerate

Nitrate + Nitrite P or G 200ml 48 hrs/28

days

ASAP &

refrigerate

Nitrite P or G 100ml none/48 hrs ASAP &

refrigerate