LaMotte SMART Colorimeter, Operator'S Manual

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will allow for any expansion. Any condition which might affect the
sample should be listed.
Sub-surface sampling is required to obtain a vertical profile of streams,
lakes, ponds, and reservoirs at specific depths. This type of sampling
requires more sophisticated sampling equipment.
For dissolved oxygen studies, or for tests requiring small sample sizes, a
Water Sample Bottle (LaMotte Code 1060) will serve as a subsurface or
in-depth sampler. This weighted device is lowered to the sampling depth
and allowed to rest at this depth for a few minutes. The water percolates
into the sample chamber displacing the air which bubbles to the surface.
When the bubbles cease to rise, the device has flushed itself
approximately five times and it may be raised to the surface for
examination. The inner chamber of the sampling device is lifted out and
portions of the water sample are carefully dispensed for subsequent
chemical analysis.
A Snap-Plunger Water Sampler (LaMotte Code 1077) is another
“in-depth” sampling device which is designed to collect large samples
which can be used for a multitude of tests. Basically, this collection
apparatus is a hollow cylinder with a spring loaded plunger attached to
each end. The device is cocked above the surface of the water and
lowered to the desired depth. A weighted messenger is send down the
calibrated line to trip the closing mechanism and the plungers seal the
sample from mixing with intermediate layers as it is brought to the
surface. A special drain outlet is provided to draw off samples for
chemical analysis.
n
Sampling of Closed System
To obtain representative samples from confined water systems, such as
pipe lines, tanks, vats, filters, water softeners, evaporators and
condensers, different considerations are required because of chemical
changes which occur between the inlet and outlet water. One must have
a basic understanding of the type of chemical changes which occur for
the type of equipment used. Also, consideration should be given to the
rate of passage and retaining time for the process water.
Temperature changes play an important part in deciding exactly what test
should be performed. Process water should be allowed to come to room
temperature, 20–25°C, before conducting any tests.
When drawing off samples from an outlet pipe such as a tap, allow sample
to run for several minutes, rinsing the container several times before
taking the final sample. Avoid splashing and introduction of any
contaminating material.
SMART COLORIMETER 7