If the instructions issued
require the vessel's tanks to be kept closed and if no means are
available to take measurements or samples through vapour lock access
points, then close reconciliation of vessel/shore quantities may be
impossible. Readings from automatic gauging equipment should
All responsible parties should
be informed if any of the gauging equipment or tank or meter facilities
have a known bias. Documentation of these deviations should
be available for inspection by all responsible parties and must be used
in preparing volume reconciliation. Possibilities for known
bias errors include (but not limited to) water, snow, ice or debris on
floating roof tanks.
Measuring processes and
procedures should be performed by adequately trained personnel
only. If the procedures cannot be performed for any reason
(such as a breach of a safe environment or due to physical constraints,
governmental or terminal restrictions, conflicts against contractual
agreements or any other problems), the inspection report should include
a complete, detailed explanation. Measurement personnel are
responsible for ensuring the use of proper safety, measurement and
sampling equipment (intrinsically safe).
The vessel's master and/or
designated representative and shore supervisory personnel should be
familiar with the scope of the cargo inspection procedures and aware of
the safety procedures unique to the product being transferred (such as
presence of H2S in cargo). And in this
respect, copies of the relevant documents should be available for
reference on board and ashore.
If simultaneous ballasting or
de-ballasting must be performed during cargo operations, this should be
recorded in the inspection report with reasons and comments on the
degree of segregation that was maintained throughout the operation.
All the procedures described
and recommended shall be accomplished with strict adherence to the
safety requirements that are specified in the International Safety
Guide for Oil Tankers and Terminals; API RP 2003, the Inert Flue Gas
Safety Guide as amended from time to time, or other specific
requirements by owners, operators and state and federal
authorities. Applicable state and federal regulations must
also be obeyed. Careful attention must be given while
sampling and manual gauging to the relaxation time and other safety
requirements for most petroleum cargoes that can accumulate a static
The shipment of petroleum
products requires stringent quality control during the loading,
transport, and discharge operations. Consequently, it is
important to determine whether a vessel is suitable to the shipper's
compatibility criteria so that the product will not be contaminated or
safety of personnel or cargo compromised.
Safety procedures designated by
the employer, the vessel's operator and other concerned parties must
also be observed at all times. The International Safety Guide
for Oil Tankers and Terminals and appropriate Oil Companies
International Marine Forum (OCIMF) and API publications should be
consulted for additional safety information.
Petroleum vapours and
associated substances including hydrogen sulfide may cause
unconsciousness or even death. During and after the opening
of the gauge hatch, all personnel should stand far enough away and
giving due consideration to the wind direction, to minimize the risk of
inhalation of vapours.
Since toxic vapours or oxygen
deficiency cannot be detected safely by smell, visual inspection or
judgement, appropriate precautions should be taken to ensure protection.
Provisions should be made for
appropriate exposure monitoring, protective equipment for personnel and
emergency rescue procedures. When it is necessary, personnel
should have suitable respiratory protection prior to entering the gauge
site and during the gauging procedure. The protection
equipment should be examined for validity and for effective its time of
& Fire Considerations
Personnel who handle
petroleum-related substances, as well as other chemical materials,
should be familiar with their physical and chemical characteristics
including, the potential risk of fire, explosion and reactivity - and
with the potential risk of toxicity and other health hazards with their
respective emergency procedures.
Personnel should be alert to
avoid potential sources of ignition and should keep containers of
materials closed when not in use.
API publications 2217 and 2026
any any applicable regulations should be consulted when sampling
requires entry into confined spaces.
particular materials and conditions should be obtained from the
employer, the manufacturer or the supplier of the material or from the
material safety data sheet and adequately studied before it is handled
or even approached.
of text taken from API - MPMS Chapter 17 Marine Measurement