Sample Transport and Storage - Field Sampling: Principles and Practices in Environmental Analysis - page 210

samples to be shipped to the analytical laboratory. Samples will be analyzed immediately,
and thus will not need storage.
8.10. FIELD LABORATORY HANDLING
The analysis to be done immediately in the field or at the field laboratory is given in
Chapter 10. This includes such things as pH, electrical conductivity (EC), and dissolved
oxygen in the case of water samples. For pH and EC the analysis can be done directly on
the samples in the field as they are taken; that is, the samples need not be dried and
sieved. In some cases, however, it may be desirable to bring samples to the field
laboratory to sieve if they contain a lot of plant material or large rocks, gravel, and so
forth; otherwise a minimum of handling is recommended.
Although the above analyses are straightforward and not delicate, care still must be
taken to obtain accurate results. The word delicate is used to indicate that small changes
in the way the analysis is carried out will usually not result in a change in the results
obtained. For instance, slight dilution of the highly buffered solutions used for
standardizing a pH meter will cause little, no, or insignificant changes in the measured
pH. This does not mean that care need not be taken in doing the analysis, however. It
does.
8.11. TRANSPORT TO THE COMMERCIAL LABORATORY
A chain of custody (COC) form and other forms (see below) as required by the laboratory
must be started in the field as the samples are taken and be continued by the receiving
laboratory. Before shipping, however, the analytical laboratory is notified because it
needs to be ready to handle and store the samples in such a way that the components of
interest are preserved.
Commercial carriers are usually used to transport samples to the laboratory for
analysis. An ideal situation would be one in which the commercial analytical laboratory
is close enough to the field being sampled that the samples can be locally transported.
This situation does not often happen, and most often the samples will need to be shipped
to the laboratory using a commercial carrier. The carrier should be chosen so that the
transit time is no more than 1 day, if at all possible. Usually the project manager at the
analytical laboratory will be able to suggest carriers and shipping requirements.
Just as individual samples must have traceable numbers, so also must lots have
traceable shipping numbers. Registered or certified mail is traceable, but may not be
sufficient for the numbers and weights of samples that need to be shipped. Companies
such as Federal Express or UPS assign traceable numbers to shipments and will often
pick up samples at a designated location. This decreases handling and thus increases
security. Using one of these carriers the progress of the sample from pickup to delivery is
traceable, accessible, and can be followed using a computer and the Internet.
In many cases shipment will involve air transport. Very specific restrictions are applied
to samples shipped by air. Different types of samples (i.e., samples containing different