Note 1
Certain products, such as esters (acetates, phthalates, etc.) and chlorinated or brominated materials can react with water to form acidic compounds.
These products are suitable for storage in coated tanks when dry. Such products must have a maximum water content of 0.02% (200 ppm), be free from acids and carried in completely dry tanks. Subsequent water contamination must be avoided. Water washing of the tank is only acceptable after full recovery of the coating and should be avoided whenever possible.

Note 2
These products may cause some surface discolouration of the coating.
They are variable in composition, depending on the source, and consequently the effects on the coating can also differ. Subsequent cleaning of the tanks may be difficult so that contamination of subsequent cargoes may occur.

Note 3
Vegetable and animal oils, fats, greases and waxes are esters of polyols with fatty acids, and nearly always will contain free fatty acid.

If in contact with water at higher temperatures these esters can saponify, resulting in increased free fatty acid content. Free fatty acids, especially the short chain types, can be very aggressive to tank coatings. Thus, during loading, storage and discharge the acid values should not exceed the maximum values indicated in the table. 

 Tank Coating System Maximum acid value
(acc. to ISO 660-1996)
Approximate Percentage 
Free Fatty Acid
 Sigma PhenGuard

No Limit

up to 100 %

 Sigma NovaGuard

100

30 - 50 %

 SigmaGuard 720 (S'guard EHB)

20

6 - 10 %

 SigmaGuard 750 (S'Silguard MC)

5

1.5 - 2.5 %



The acid value according to ISO 660 - 1996 is the only accepted method to determine a cargo’s suitability for carriage. The Free Fatty Acid percentages given are a guide as the acid value is dependant on the molecular weight of the Fatty Acid(s).

The fatty acids (including fatty acid distillates and acid oils) accepted in this list can be transported provided they comply with the following criteria:
- the water content must be limited to 1,0 percent maximum.
- no free mineral acid content is permitted.

Note 4
These aggressive cargoes can only be carried when the system post cured or hot cured.

Post Cure
may be obtained by:
A service period of 3 months with non-aggressive cargoes (without notes 4, 7, 8 and/or 11) or empty tanks. 

For double hull vessels this may be achieved by carrying a hot cargo such as lubricating oil, animal oil or vegetable oil in full cargo tanks at a constant temperature of 60 degrees centigrade for 5 days, or 50 degrees centigrade for 10 days.

For single hull vessels and areas in direct contact with seawater the curing is dependent on the seawater temperature. As detailed in the table below.
Sea Water
temperature in ºC
Minimum Hot Cargo
temperature in ºC
Minimum 
Time /  days

10

70

10     

10

85

  6     

20

60

10     

20

75

  6     

25

50

10     

25

65

  6     



Hot Cure may be obtained by:
Using hot (sea) water through the butterworth washing system. For more detailed information please see the Appendix of system sheet 3322.

For a hot cure it must be ensured that the entire coated surface has attained the minimum specified temperature/time requirements.
 
For transport of Methanol and Vinyl Acetate Monomer (VAM) in Sigma Phenguard coated tanks a hot cure is required.

After transport of cargoes with Note 4, the system must be restored to its original condition. This may be obtained by forced ventilation until the tank is in a steady state gas free condition
(guideline: 1% of the LEL - see Ventilation) followed by carriage of non-aggressive cargoes (without notes 4, 7, 8 and/or 11) or empty tanks for a period of at least 10 days.

Note 5
Products in this class are proprietary materials and can be transported, provided that the pH is within the range 5,5 to 9.

Note 6
The tank coating is resistant to the cargo as specified.
However the stability of the cargo may be adversely affected and therefore carriage of this cargo should not exceed 90 days. Prior to loading of this cargo, tanks should be suitably cleaned and the level of inhibitor present in the cargo should be checked to ensure compliance with the requirements of the cargo.

Note 7
Carriage of this cargo should not exceed 30 days.
Before another cargo with notes 4, 7, 8 and/or 11 is transported, the coating has to be restored to its original condition. This may be obtained by ventilating the tank thoroughly until the tank is in steady state gas-free condition (see information Ventilation), followed by carriage of non-aggressive cargoes (without notes 4, 7, 8 and/or 11) or empty (dry air) for a period of at least 10 days.

Note 8
Carriage of this cargo should not exceed 90 days.
Before another cargo with notes 4, 7, 8 or 11 is transported the coating has to be restored to its original condition. This may be obtained by ventilating the tank thoroughly until the tank is in a steady state gas-free condition (see Ventilation). by carriage of non-aggressive cargoes (without note 4, 7, 8 and/or 11) or empty (dry air) for a period of at least 10 days.

Note 9
Lubricating oil, excluding chlorinated, brominated, phosphated and ester types may be carried at temperatures up to 70 ºC (80 ºC for loading or discharge). It is necessary to establish that cargoes of lubricating oils are not of the types listed as exclusions.

Note 10
Molasses can be carried when the pH of the product is between 4 and 11. After tank cleaning diluted solutions of molasses should be removed within 24 hours or, when acidic, should be neutralised by an alkaline tank cleaning product to a pH between 5 and 9.

Note 11
Before loading these cargoes it is essential that the tank is dry and free from moisture.
After carriage of these cargoes, tanks should not be brought into contact with water. No steam, ballast water, or aqueous cargoes must come into contact with the coating before it is restored to its original condition. This may be obtained by ventilating the tank thoroughly with dry air (relative humidity lower than 80%) until the tank is in a steady state gas-free condition (guideline 1% the of LEL - see Ventilation). After ventilation, non-aggressive (without notes 4, 7, 8 and/or 11) and non aqueous cargoes (maximum water content 1%) should be carried for a period of at least 10 days - an empty tank (dry air) is also acceptable. 

Methanol or Ethanol cargoes must be pure (contamination with acetaldehyde, formaldehyde, formic acid, acetone and acetic acid should be below 100 ppm per contaminant).
The pH of Ethanol should be between 4 and 7. Methanol should be "water free" (maximum permissible water 0,10 % or 1000 ppm). Samples of the Methanol or Ethanol must be taken prior to both loading and discharge. The samples have to be sealed, properly marked and dated and retained on board for a minimum of 6 months after discharge of the Methanol or Ethanol cargo.

Note 12
These amines can be transported but must have a maximum water content of 0.05% (500 ppm). If water is present the alkalinity may increase to a pH higher than 10. To prevent contamination by water the tank must be completely dry at the time of loading and the cargo should preferably be transported under a dry nitrogen gas-blanket.

Note 13
When full cure according to the times specified in the data sheet is reached SigmaGuard 750 (Sigma Silguard MC) is resistant to phenols and cresols.
However, the tanks must be ballasted or water cleaned at least once before transporting these products.

Note 14
Crude oils and other crude derivative products can normally be transported and stored in SigmaGuard 750 (Sigma Silguard MC) coated tanks.
However, some crude oils/derivative products contain acids and are thus aggressive to zinc silicates, especially when heated and in the presence of water. Cargoes with a neutralisation number above 0,4 (ASTM D-664) are not permitted. The pH of water present in these crude products should not be outside the range of 5,5 to 9.

Note 15
These products can be carried only in completely dry tanks without any water contamination, maximum water content of the cargo should be 0,015% (150 ppm).

Note 16
This is a generic name. Most of these cargoes can be transported but it should be established that no notes are included under the specific type name of such a cargo elsewhere in the list. 

Note 17
If SigmaGuard 750 (Sigma Silguard MC) coated tanks are also available, it is recommended that they should be used to carry this product.

Note 18
Storage of this cargo should not exceed 90 days. Before carriage of another water (containing) cargo, the coating must be restored to its original condition.
This may be obtained by ventilating the tank thoroughly until the tank is in a steady state gas-free condition (see Ventilation), followed by carriage of non-aggressive cargoes, (without notes 4, 7, 8 and/or 11) or empty (dry air) for a period of at least 10 days. Extended service life of the coating when carrying aggressive cargoes will be obtained by avoiding ballasting of the tanks.

Note 21
Automotive gasolines can vary widely in composition. Addition of considerable amounts of aromatic and/or oxygenated solvents are common. When these cargoes have to be transported the tank coating should be fully cured. 
Blending of automotive gasolines with above mentioned additives in the tank is not acceptable.

Limits for oxygenated solvents (in volume) as set out in European Directive 2003/17/EC Annex III
Type: Petrol

 Parameter (1)  Unit   Limits (2)
   

 Minimum

 Maximum


 Hydrocarbon analysis:

 - Olefins

 - Aromatics

 - Benzene



 % v/v

 % v/v

 % v/v



-

-

-



 18.0

 35.0

   1.0
 Oxygen content

 % m/m

    2.7
 Oxygenates:
.

 - Methanol (stabilising agents must be added)

 - Ehtanol (stabilising agents may be necessary)

 - Iso-Propyl Alcohol

 - Tert-Butyl Alcohol

 - Iso-Butyl Alcohol

 - Ethers containing five or more carbon atoms
   per molecule

 - Other oxygenates (3)



 % v/v

 % v/v

 % v/v

 % v/v

 % v/v

 % v/v

 
 % v/v



-

-

-

-

-

-


-

 

   3

   5

 10

   7

 10

 15


 10
  Sulphur content

mg/kg
mg/kg

-
-

 50 
 10 (4)

  Lead content
 

 g/l

-

   0.005

  1. Test methods shall be those specified in EN 228:1999. Member States may adopt the analytical method specified in replacement EN 228:1999 standard if it can be shown to give at least the same accuracy and at least the same level of precision as the analytical method it replaces.
     
  2. The values quoted in the specification are "true values". In the establishment of their limit values the terms of ISO4259 "Petroleum products - Determination and application of precision data in relation to methods of test" have been applied and in fixing a minimum value, a minimum difference of 2R above zero has been taken into account (R = reproductibility). The results of individual measurements shall be interpreted on the basis of the criteria described in ISO 4259 (published in 1995).
     
  3. Other mono-alcohols and ethers with a final boiling point no higher than that stated in EN 228:1999.
      
  4. In accordance with Article 3(2), by no later than January 2005 unleaded petrol with a maximum sulphur content of 10 mg/kg must be marketed and be available on an appropriately balanced geographical basis within the territory of a Member State. By 1 January 2009 all unleaded petrol marketed in the territory of a Member State must have a maximum sulphur content of 10 mg/kg.


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