Abstract: Applying the methods of system analysis, the system goal of metrological support for petroleum product testing is justified; the
goal is to obtain accurate, complete, reliable measurement information about the composition and properties of petroleum products,
which is achieved via solving two subgoals:
а) creating conditions for obtaining the testing results having the required accuracy;
б) achieving such a state of the testing progress that would ensure the receipt of accurate and reliable measurement information
about the petroleum product composition and properties.
The disclosure of the first and second subgoals forms the structure of the metrological support system intended for testing of
petroleum products, which is a complex of conventional elements and processes of metrological support and procedures for
controlling the process of petroleum product testing. In the structure of the metrological support system under development purposed
for petroleum product testing, both well-known and generally recognized elements and processes of metrological support, as well as
new elements and processes that capture the specific features of the testing process as a subject of metrological support. In particular,
it is proposed to use validation and verification procedures to confirm the metrological applicability of testing methods intended for
petroleum products, and the need for verification of operators, who carry out the tests, is given. In order to reduce the petroleum
testing inaccuracy, the need to include measures to control the process of petroleum product testing in a lab by way of the
metrological support system is justified. The following sequence of actions for metrological support of petroleum products testing is
shown; it allows achieving such a state of the testing process, in which the tolerance of the obtained results is within certain
statistically adjusted limits and the reliability of the test results is confirmed by the stability of the tolerance values.
Index terms: petroleum products, testing, measurement of composition and properties, metrological support, process control.