SKC Limited Universal Pump Step By Step Guide - Manual (Page 14)

Page 12 224-G3 Issue C www.skcltd.com
Gas & Vapour Sampling using Sorbent Tubes
7. At the end of the sample switch the pump off
and note the finish time of the sample. Remove
the sample train from the worker, and once away
from the sample location re-check the tube flow
rate. Ensure that the flow rate check is carried out
as quickly as possible to minimise the chance of
collecting anything that may affect the final result.
When the sorbent tube is removed from the tube
holder, both ends of the tube should be immediately
capped with the red covers supplied. The start and
finish times, sample duration, worker's name, start
and finish flow rates and any other relevant details
of the sample should be noted down and indexed
to the sorbent tube by number or code.
The importance of blanks:
Sample blanks are in general ignored by a lot of people,
but do offer an important and required benchmark for
accurate samples. Prepare and handle a sorbent tube
the same way as the ones being used for the actual
sample. DO NOT expose the blank tube to any air and cap it immediately with the red covers. When sending
the used tubes for analysis include the non exposed
blank as well. This will allow the laboratory to test the
blank and take into account any variations which are
then applied to the exposed samples.
Tube Caps