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Quality Requirements Edition 6.0 European Enamel Association

7.21. QUALITY REQUIREMENTS FOR PORCELAIN AND VITREOUS ENAMELLED INDUSTRIAL TANKS – 2 GROUP
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7.21.1 Application area

These requirements are applicable for enamelled panels for bolted steel tanks for the storage or treatment of water or municipal or industrial effluents and sludges (not chemical
vessels). This section (7.21) refers exclusively to the tanks dedicated to the below listed applications:
- Cylinders in biogas digester for agricultural waste (excluding the roofs exposed to gaseous zone, see section 7.20)
- Cylinders in municipal mesophilic digesters (excluding the roofs exposed to gaseous zone, see section 7.20)
- Cylinders in municipal sludge treatment (excluding the roofs exposed to gaseous zone, see section 7.20)
- Municipal sludge / sludge cake storage
- Filter tanks
- Storm / fire water
- Potable waters DWI listed, Reg. 31 and NSF/ANSI/CAN 61

See also for other application areas the section 7.20 QUALITY REQUIREMENTS FOR PORCELAIN AND VITREOUS ENAMELLED INDUSTRIAL TANKS – 1 GROUP
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7.21.2 Test methods

Item Name Applicable standards
3.5 visual assessment EEA 8.7
3.9.3 determination of the hardness referring to Mohs EN ISO 6769
4.3 measurement of the thickness of the enamel coating EN ISO 2178, EN ISO 2360, EN ISO 1463
4.4 determination of the resistance to chemical corrosion by EN ISO 28706-1/9
acids at room temperature

4.5 determination of the resistance to chemical corrosion by boiling citric acids EN ISO 28706-2/11
4.6 determination of the resistance to chemical corrosion by boiling water and/or water EN ISO 28706-2/14
vapour

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