A “failed” wall wash can result from:
If you do not pay enough attention to the exact requirements of the Customer’s wall wash specification, which of the following may result?
The basic routine laboratory tests, that we run on board include:
Wall wash results should be recorded for the following reasons:
The two kinds of detectable odour in a wall wash sample are:
A drying-oven Non-Volatile Matter test cannot be effectively done on board a ship, because:
The equipment works on a different voltage.
Spares are difficult to obtain in many parts of the world.
A sufficiently stable and vibration-free platform cannot be provided for the required measurements.
Ships laboratories cannot be maintained at constant room temperature.
A wall wash should not be taken from a hot bulkhead, because:
Any contaminants will stick to the surface.
Any contaminants will evaporate.
Too much Methanol will evaporate.
The Officer (or Surveyor) will burn his hands.
A wall wash should not be taken from a wet bulkhead, because:
Any contaminants will stick to the surface.
Any contaminants will collect at the bottom of the bulkhead.
The Methanol will evaporate on contact with the moisture on the bulkhead.
Surface tension and dilution will lead to a less efficient wall wash.
All cargoes loaded into Stainless Steel tanks require a wall wash standard of tank cleanliness:
An Inhibitor in a last cargo will almost certainly influence the result in this routine shipboard laboratory test:
Another name for the Hydrocarbon test is “Water Misidentification”:
Blue graduation marks on the side of a test tube may lead to:
Misinterpretation of low levels of Hydrocarbons.
Increased levels of Hydrocarbons.
Poor analysis of Permanganate Fade Time.
Misinterpretation of high levels of Chlorides.
Certain ships routinely carry a stock of wall wash equipment in excess of the recommended levels, if:
They regularly trade in the Far East.
They work in an intensive high-spec trade.
They carry a lot of acid cargoes.
Given the specification and observed condition as listed, what would be the priority in the next phase of tank preparation?
Heavy smokers may, in particular, have a problem accurately conducting this routine laboratory test:
Hot bulkheads should be avoided for wall wash, because:
Of the high evaporation rate of the Methanol.
ASTM specifications require the bulkhead to be between 15 °C and 25 °C.
Accurate analysis is dependent on temperature at the time of wall wash in the tank.
How many drops of Silver Nitrate solution are added to the sample in a Chloride test?
Ideally, a standard wall-wash should be run over which of the following distances?
75 cm in open areas, 25 cm under frames.
If Bleach products have been used in a tank cleaning process, and not properly rinsed away, the following is most likely to be noted in a wall wash analysis:
If you encountered a new wall wash or analysis procedure, you should:
Forward full details to Company Operations Department.
Advise the Ships Superintendand.
Inform the Purchasing Department.
In a Hydrocarbons test, the presence of moderate to heavy Hydrocarbons is indicated by:
A milky white discoloration.
A silver sheen on the surface of the sample.
A translucent bluish tint.
In a Hydrocarbons test, the presence of slight Hydrocarbons is indicated by:
A milky white discoloration.
A silver sheen on the surface of the sample.
A translucent bluish tint.
In a Permanganate Fade Time test using Methanol, at what temperature should the samples be maintained?
In a Permanganate Fade Time test, how long should the samples be allowed to “stabilize” before the Permanganate solution is added?
Approximately 45 minutes.
In a Permanganate Fade Time test, samples should be checked against the standard at the following interval:
After 30 minutes and every 10 minutes thereafter.
Inhibitor in a previous cargo commonly affects Permanganate Fade Time test results:
Maintaining the samples at a constant temperature is a necessary part of the Permanganate Fade Time test procedure:
Most shore laboratories follow analysis standards laid down by:
Customer’s Cargo Handling Manuals.
Of the four problems listed below and assuming all are included in a customer specification, which would be the priority?
Appearance (some suspended matter).
Orange or red particles noted in a wall wash sample are an indication of the presence of:
Undissolved Potassium Permanganate.
Permanganate Fade Time is defined as:
The time elapsed from taking the wall wash until the colour of the sample matches the colour of the ASTM Colour-Standard.
The time elapsed from the “Start” time in the laboratory test until the colour of the sample matches the colour of the ASTM Colour-Standard.
The time for a prepared Permanganate Solution to go off-colour.
The time measured between placing the samples in the cooler until they reach 15 °C.
Permanganate Fade Time test samples should start off with the following colour:
Permanganate Fade Time test are run for:
As long as a customer’s specification requires.
As long as the Chief Officer chooses.
Regular marker pens should not be used to identify sample jars, because:
You may need to remark them at a later stage.
Methanol may dissolve the marker ink.
Methanol will turn the marker ink sticky and it may get transferred to the wall wash funnel.
Under the regulations, coloured marker pens are prohibited.
Residual Odour is defined as:
The smell normally associated with a wall wash medium.
The smell associated with a clean and dry tank coating.
Any odour present in a cargo tank immediately prior to loading.
A foreign smell, typically from a previous cargo, found in a wall wash sample, but not present in a “blank”.
Soapy bubbles noted on the top of a wall wash sample in a test tube are a likely indication of:
Residues from an oil based cleaning agent.
Residues of a water based cargo.
Residues from a detergent based cleaning chemical.
Standard wall wash technique usually involves running a sufficient quantity of industrial water down a tank surface, until all traces of cargo residue disappear from a collected sample:
The Ultraviolet Spectrum test is run to detect:
High levels of solid particle impurities.
Low levels of dissolved impurities.
The dish used in a shore laboratory Non-Volatile Matter test is commonly made from:
The following amount of Potassium Permanganate Solution is added to the sample in the Permanganate Fade Time test:
The following important information should be prominently posted in the ships laboratory:
The Deck Watch keeping Schedule.
Material Safety Data Sheets for any chemical in use.
The letters “G. C.” in the shore laboratory test stand for:
The letters “N. V. M.” stand for:
The most apparent effect of samples left standing in test tubes is:
Permanent etching of the glass.
Accelerated discoloration of the glass.
Chemical reaction with any Hydrocarbons present.
Very slight inaccuracies in certain laboratory tests.
The most likely source of Hydrocarbons detected in a wall wash sample is:
Dust in the laboratory Methanol.
Polluted air drawn into the tank.
Traces of previous cargo.
The over-riding principle behind a wall wash and the subsequent analysis is:
Selecting a good part of the tank, in order to ensure a “pass” result.
The purpose of a wall wash is to determine:
Whether a tank meets customer cleanliness requirements.
Whether a tank meets company maintenance requirements.
If a tank is safe to enter.
The ratio and components used in the preparation of a Permanganate Solution are:
0,2 g Permanganate crystals to 0,5 ltr Deionised Water.
0,5 g Permanganate crystals to 0,5 ltr Deionised Water.
0,1 g Permanganate crystals to 0,5 ltr Methanol.
0,1 g Permanganate crystals to 0,5 ltr Deionised Water.
The risk of odour contamination is most likely in which of the following:
Tank lid and cleaning hatch packing’s.
The sealed reference standard used in a Permanganate Fade Time test is:
A Potassium Chloride 600 colour standard.
A Potassium Chloride 530 colour standard.
An API 500 Colour standard.
A Platinum Cobalt 500 colour standard.
The significant difference with a Whatman Filter Paper test is that it:
Commonly includes a sample taken from the tank bottom.
Involves more samples per tank.
It is more difficult to pass.
It is only performed in Japan.
The two components in a Hydrocarbon test “blank” standard are:
Wall wash sample and Deionised Water.
Wall wash sample and Methanol.
Methanol and Silver Nitrate Solution.
Methanol and Deionised Water.
The wall wash procedures in this programme and those used by the majority of shore laboratories, are built around industry standards issued by the following organisation:
The American Society for Testing and Materials.
The American Petroleum Institute.
To assess the Appearance of a wall wash sample, we:
Send the sample ashore for laboratory analysis.
Examine the sample in good light and compare to a sample of “good” Methanol.
Add Silver Nitrate and look for cloudiness.
Heat a small sample of the wall wash and check for any residues remaining.
To determine the presence of Chlorides in a wall wash sample, we add:
2 ml of 20 % Potassium Permanganate Solution.
5 drops of 10 % Silver Nitrate Solution.
2 mg of Potassium Permanganate crystals.
5 ml of 3 % Hydrochloric Acid.
Under normal handling conditions, a Permanganate Solution will last for approximately:
Wall wash samples will not really be affected by an occasional drop of sweat:
When performing a Hydrocarbons test, the sample should be viewed:
Looking down through the tube against a black background.
Looking sideways through the tube against a good light.
Looking sideways through the tube against a black background.
Looking down through the tube against a white background.
Where possible, a wall wash stream should be run for:
Which of the following descriptions is best applied to the “Appearance” of a wall wash sample?
The cloudiness of the sample.
The overall clarity and content of the sample.
The colour of any sediment in the bottom of the sample.
The number of floating particles (only) in a measured amount of the sample.
Which of the following is a false statement?
Methanol dissolves most kinds of marker ink.
A random area on each bulkhead is selected during wall wash to guarantee, so far as is practicable, a representative coverage.
Moisture on a bulkhead may lead to the build-up of surface tension, which is resistant to Methanol.
Brown “burn marks” around a Methanol stream are specifically indicative of salt crystals remaining on the bulkhead.
Which of the following is unlikely to be the source of Hydrocarbons found in wall wash analysis?
Which of the following should be available in the ships laboratory?