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Starting up cargo is one of the most critical periods of any cargo operation. Extraordinary vigilance and care both onshore and onboard are mandatory. Special attention should be paid to pipeline pressures and pressure venting systems. Frequent checks must be made to detect any leakages to the sea, on deck, or into other tanks/spaces.
When the chief officer is satisfied that his vessel is ready to load cargo, that all necessary personnel are available to start loading, and that all required inspections have been completed and documented, then the first manifold valve can be opened and he can advise the shore terminal operator that he is ready to load cargo. This must be done in a way which clearly indicates which manifold valve is open to receive the first cargo. If all manifold valves are not open at the start, that fact must be clearly indicated to the person in charge at the shore terminal.

Case study
A product tanker was moored at an oil terminal near Houston, preparing to load heating oil. When all preparations were complete, the tanker's cargo watch officer advised the berth supervisor that they were 'ready to load'. However the manifold valves had not yet been opened. The dock supervisor instructed the shore control room operator to start the heating oil pump to the ship. Before the ship's crew could open their manifold valve, the 20,000 bbl./hour pump was started. The loading arm could not withstand the hydraulic surge of heating oil against the closed valve. It failed catastrophically, showering the berth area with heating oil. The operator of a push tug in the adjacent berth started his engines to back clear of the spill. A source of ignition in the tugs engine room ignited the oil vapours. The tug exploded and sank with its two crew. The dock and port stern of the tanker were enveloped in flame. Quick action by the ship's crew, helped by a favourable wind, soon contained and extinguished the fire on deck. The refinery fire brigade extinguished the dock fire.

Case analysis
The essential cause of this incident was a failure of ship-shore
communications. During the pre-loading conference, the communications protocol to be used for all basic and emergency cargo communications should be discussed. The shore superintendent must receive a clear indication that the ship is ready to load and that the necessary manifold valve is open. A suitable exchange would be as follows:

Ship to shore: "Berth three, this is the Neverspill. We are ready to load fuel oil in our Starboard loading line."
Shore to ship: "Neverspill this is berth three, understand you are ready to begin loading fuel oil on your starboard line. Is your manifold valve open?"
Ship to shore: "Berth three, this is Neverspill, our fuel oil manifold valve is open; you may start the pump."
Shore to ship: "Neverspill, this is berth three, we are opening the shore tank and will advise you when we have started the pump."
Ship to shore: "Berth three, this is Neverspill, Roger, out."
Shore to ship:(later): "Neverspill, this is berth three, we have started the pump; please advise when you are receiving cargo."
Ship to shore: "Berth three, this is Neverspill, we are receiving cargo at (time)."

This may seem like an unnecessary number of words for such a simple operation, but considering the consequences of the incident described above, a few extra words seems like a good investment! The important point is that positive feedback, verification, and disciplined communications procedures are essential to properly conducting the start and all aspects of every cargo operation.

3.16.1 Starting samples

Case study
In 1982, a vessel loading two grades of gasoline, leaded and unleaded, discovered upon completion of loading that there was substantial contamination of the unleaded parcel by the leaded parcel. When the case reached the Canadian courts, five years later it was essentially decided on statements of probability by expert witnesses and by the presence of a single sample drawn from the dock which showed the unleaded line was contaminated by lead.

Case analysis
In this case, a single sample, not even drawn by dock or ship's staff, provided a precariously thin exhibit on which to base the ship's defence. Thousands of dollars in legal and expert witness fees would have been avoid if the cargo had been thoroughly sampled according to standard procedures. While a product tanker may have paid scrupulous attention to the preparation of its tanks and pipelines for the cargo, there is no guarantee that the shore has done the same. A line displacement may have been incorrectly calculated, or the wrong hose used. Either error can contaminate a tank or parcel of cargo.
When each product grade is started, the cargo watch officer must have a crew member standing by the sampling connection at the manifold, to sample the first flow of oil into the ship. This sample should be suitably labelled and retained along with the other cargo samples.
Refined products should be started on one tank only, until it is verified that the correct product is being loaded. If the wrong product is received, only one tank will have been contaminated and only one tank will require cleaning before the correct grade can be loaded. Where no manifold sample point is fitted, cargo should be loaded into one tank and a 'frame sample' or bottom sample drawn and tested as soon as possible.

3.16.2 Loading rates and static generative cargoes
Cargo should be started slowly, by gravity flow from the shore whenever possible. A crew member (the same one taking the starting sample), should remain at the manifold connection, observing it for any leakages. When cargo is seen to be entering the tanks by gravity, the shore operator can be instructed to start the shore pumps. The manifold connection must be under continuous observation until the full loading rate is reached.
Ships on charter are required by their charter parties to load cargo, whether single or multi grade, as fast as they can safely receive it. It is up to the master to determine how fast the ship can safely load a particular cargo at a facility. To make this decision, he must give full consideration to the recommendations of the International safety guide for oil tankers and terminals (ISGOTT), to the owner's instructions and to any special circumstances.
Loading rates for non-static accumulator cargoes are limited by the physical ability of the vessel's tank structure, vent and cargo piping systems to withstand the loading pressures. The pressure in the pipelines must not exceed the maximum permitted pressures
(normally 125 psi) and pressures in the tanks should not exceed 1400 mm (2 psig).
The vent line pressure should not exceed that indicated by the designer/builder and must be closely monitored at terminals where loading rates are high. (The builder's maximum vent pressure is based on rates for loading all tanks simultaneously. Rates must be reduced accordingly for a smaller number of tanks being loaded).
The final consideration in setting a maximum loading rate is the competence of the cargo watch officers. Maximum possible loading rates should not be used if the deck officers have recently been changed, lack experience, or are unfamiliar with the vessel.
Acceptable maximum loading rates are normally rates which produce between six and ten meters per second pipeline velocity.
Static accumulator oils are distillates (clean oils) with low conductivity and a corresponding slow dissipation of any static electricity charge acquired through handling. Kerosene and Kerosene based jet fuel (JP-1), are two of the most significant static accumulator oils. Others are indicated in the ISGOTT manual. Any distillate must be treated as a static accumulator unless the product contains an antistatic additive. Static accumulator oils must be loaded with procedures which minimise static charge generation and accumulation. When a static accumulator oil, such as natural gasoline or naphtha is loaded, the initial loading rate must be a flow of less than one meter per second in the cargo pipelines. For a vessel with 510 mm (24") loading branch lines, this flow rate would be less than 676 cubic meters per hour. The initial slow loading of static accumulator oils must continue until the bottom longitudinals and the cargo tank oil inlet are covered and all splashing and surface turbulence has stopped. Since the surface of the cargo in closed-loading tanks cannot be observed, the chief officer will have to indicate in the cargo orders the ullage which corresponds to the required slow filling rate level. The cargo level must be measured by permanently installed tank gauging equipment. Portable gauging equipment should not be introduced into a tank while loading a static accumulator oil or for thirty minutes after loading stops.
After the tank bottom is covered as required, the flow rate can be increased to the maximum safe rate.
If an IGS system is fitted, tanks to receive static accumulator cargoes should always be inerted prior to loading.
Loading rates must be checked regularly by ship's personnel to ensure that the agreed loading rates are being maintained. Rates may increase without warning, especially at terminals where the same grade of cargo is being loaded to more than one vessel.

3.16.3 Bottom samples
Where the specifications of the cargo are critical and particularly if there is any question regarding the suitability of the ship's preparations to receive and carry the cargo, then loading should be stopped after tank bottoms have been placed in each cargo tank. Tank bottom samples ('frame samples'), should be taken and sent ashore for quality analysis. If the sample test results are acceptable, the ship may continue to load. If the samples are 'off-test' but by a small margin, the ship may resume loading with the expectation that the dilution of the bottoms with a full cargo of 'on-test' product will produce a cargo which will be uniformly 'on-test'. The master must be informed of any 'off-test' bottom sample results and he must contact charterers to obtain their advice. He must be a party to all discussions regarding the 'off-test' cargo and should note his protest of the situation. If samples are significantly 'off-test', the terminal may reject the ship for further loading. Alternatively, the master may refuse the cargo and should do so unless advised by charterer's in writing to continue.

3.16.4 Tank flushing
Where cargo quality is critical, particularly with respect to water, the use of flushing oil is often required. Use of flushing oil will normally be indicated in the vessel's cargo orders. When the ship is ready to load, about 50 cubic meters of flushing oil is loaded into the designated tanks. The flush oil is then stripped ashore or to a collection tank where it may be loaded on top. The collection tank is measured to confirm that it has all been recovered. The ship is then ready to load the critical cargo into the flushed tanks.
Where flushing oil is required for preparing cutback asphalt tanks for loading, fuel oil is normally used. The recovered flush oil may be loaded on top with fuel oil, or used as bunkers.

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