A line sample should always be
taken whenever petroleum or petroleum products are handled.
The purpose of line sampling, as well as any required testing, will be
specified by interested parties. The results of the line
sample analysis should be recorded in the inspection report.
For some products, it is
necessary to draw a line sample at the commencement of loading each
grade of product. These samples should be drawn at the ship
manifold. After an appropriate settling time elapses - a time
that is determined by the nature of the product - the sample should be
examined visually to verify its obvious characteristics, that is,
whether the product is water white, bright or clear. If the
visual inspection proves unsatisfactory, the loading should be
suspended and an investigation conducted. In the case of
products with no obvious signs to observe, prompt laboratory testing
for agreed specifications may be required. In any case, these
samples should be taken and retained.
The practice of loading one (1)
foot trial portions is an accepted procedure in the loading of
petroleum products. The procedure normally involves pumping a
small amount of the intended product into the vessel's tank, suspending
the loading operation and securing a sample to be tested for agreed
specifications. The purpose of this procedure is to determine
whether the loading lines and the vessel's cargo tanks have the ability
to load "on specification" product.
If contaminants are found, all
parties should be notified that compartment or compartments may have to
be off-loaded or transferred to a slop tank and another parcel loaded
and retested on "first foot".
- Meter Proving
The meter proving should be
monitored as appropriate in accordance with MPMS Chapters 4, 5 and
12.2. A Meter Prover Report should be completed and attached
to the metered quantity certificate.
Sections of text taken from API - MPMS Chapter 17 Marine Measurement