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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/carriage 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 discoloration 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 and unsaturated types, can be very aggressive to tank coatings. Thus, during loading, storage/carriage and discharge the acid values should not exceed the maximum values indicated in the table.


Maximum Acid Value

Approximate Percentage Free Fatty Acid (FFA)


No limit

Up to 100%



30 - 50%



30 - 50%



6 - 10%



6 - 10%



3 - 5%



3 - 5%



3 - 5%



1.5 - 2.5%

The acid value must be determined by ISO 660:2009. The oils and fats accepted in this list can be stored/transported, provided that they comply with the following criteria:

  • Water content < 1%
  • No free mineral acid content permitted

Note 4

These aggressive products can only be stored when the coating is post cured or hot cured.

Post cure can be obtained by:

  • A storage/carriage period of 3 months of non-aggressive products (without notes 4, 7 and/or 11) or tank left empty;
  • For insulated tanks, post cure will also be obtained after storage of a hot product such as lubricating oil at temperatures of:
    • 60°C (140°F) for 5 days, or
    • 50°C (122°F) for 10 days;
  • For non-insulated tanks and outside air temperatures below 15°C (59°F), the product temperature should be raised to 80-90°C (176-194°F).

For storage of methanol and vinyl acetate monomer (VAM) in PPG PHENGUARD coated storage tanks, a hot cure is required and cannot be substituted by a storage period of 3 months with non-aggressive products. For a hot cure it must be ensured that the entire coated surface has attained the minimum specified temperature and time requirements.

After storage of note 4 marked products, the coating has to be restored to its original condition. This will be obtained by ventilating the tank thoroughly until the tank is gas-free, followed by storage/carriage of non-aggressive products (without notes 4,7 and/or 11) or left empty for a period of at least 10 days.

Note 5

Products in this class are proprietary materials and can be stored/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 (7a)
  • 60 days (7b)
  • 90 days (7c)

Before another cargo with notes 4, 7, and/or 11 is transported/stored, 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, non-aqueous cargoes (without notes 4, 7 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°C (80°C for loading or discharge up to 48 hours). 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 neutralized 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 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/stored 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 stored/transported under a dry nitrogen gas-blanket.

Note 13

When full cure according to the times specified in the data sheet is reached, PPG SIGMAGUARD 750 and PPG DIMETCOTE 9 are resistant to phenols and cresols. However, the tanks must be ballasted or water cleaned at least once before storing/transporting these products.

Note 14

Crude oils and other crude derivative products can be transported/stored in PPG SIGMAGUARD 750 or PPG DIMETCOTE 9 coated tanks, provided that the acid neutralization number is < 0.4 (ASTM D-664), pH in the range 5.5 to 9 and mercaptan content < 0.01% (100 ppm).

Note 15

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

Note 16

Generic (non-specific) cargo name. Due to variations in composition, consult your PPG representative for specific recommendation on use. Laboratory tests may be required.

Note 17

If PPG SIGMAGUARD 750 or PPG DIMETCOTE 9 (zinc silicate) coated tanks are available, it is recommended that these are used to carry this product.

Note 18

Storage/carriage 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 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 19

Isocyanates can be carried/stored, provided sufficient precautions are taken to exclude humidity, as water will react with isocyanates and may cause unremovable deposits on the coating. Tanks which have transported/stored isocyanates must be cleaned very carefully.

Note 20

The tank lining is resistant to aviation fuels, jet fuels, etc. Specific requirements from customer or authorities may, however, exist.

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



Maximum Limits(2)

Hydrocarbon analysis:
- Olefins
- Aromatics
- Benzene

% v/v
% v/v
% v/v


Oxygen content

% m/m


- Methanol (stabilising agents must be added)
- Ethanol (stabilising agents may be necessary)
- Iso-Propyl Alcohol
- Tert-Butyl Alcohol
- Iso-Butyl Alcohol
- Ethers containing five or more carbon atoms per molecule
- Other oxygentaes(3)

% v/v
% v/v
% v/v
% v/v
% v/v
% v/v
% v/v


Suplhur content



Lead content



  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 = reproducibility). 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.

Note 22

Aqueous urea ammonia nitrate solutions can be carried, provided the free-ammonia content is at all times above 200ppm and below 2%. Residues remaining in the tanks could become very corrosive, and should therefore be prevented.

Note 23

Back-loading and regular carriage of this cargo is not recommended. Also regular transport/storage of different types of cargoes with note 23 within short intervals is not recommended.

The minimum time between discharge of this cargo and loading any cargo that also makes reference to note 23 should be at least 6 months.

Note 24

Tank lining is resistant, provided the acid content is < 0.01% (ASTM-1258) and the water content is < 0.3% (ASTM-E-202). Turbidity may develop in certain products at elevated temperatures.