When storing drinking water, material safety is non-negotiable. Regulatory bodies worldwide require that tank materials, sealants, and coatings do not leach harmful substances into the water supply. Understanding certification standards helps you specify tanks that pass inspection and protect public health.
What Is WRAS?
WRAS (Water Regulations Approval Scheme) is the UK approval body for plumbing products and materials in contact with drinking water. A WRAS-approved tank uses certified food-grade resin, gaskets, and connection fittings that have been tested for water extractives and microbial growth potential.
For projects in England, Wales, and Scotland, specifying WRAS-approved components is typically required for compliance with water supply regulations.
Other Key Standards
- NSF/ANSI 61 — North American standard for drinking water system components
- AS/NZS 4020 — Australian and New Zealand testing for products in contact with drinking water
- EU Regulation 10/2011 — European framework for food-contact plastic materials
- GB 5749 — Chinese national standard for drinking water quality
Certified Material Options
WRAS-Approved GRP / FRP Tanks
Fiberglass tanks manufactured with food-grade isophthalic or orthophthalic resin are widely used for potable water in the UK, EU, and Southeast Asia. Modular bolted panels (typically 5,000–10,000 liter standard sizes) allow flexible site assembly. WRAS-approved GRP tanks offer excellent value compared to stainless steel while meeting drinking water safety requirements.
Stainless Steel SUS304 / SUS316
Inherently food-safe when properly fabricated. SUS304 is standard for most potable applications; SUS316 is preferred for coastal areas, swimming pool balance tanks, and high-chloride environments. Stainless tanks are often accepted without separate material certification when mill certificates confirm grade compliance.
What to Request from Your Supplier
- WRAS approval certificate or equivalent test reports for resin and gaskets
- Material mill certificates for stainless steel panels (SUS304/316)
- Weld inspection reports for welded stainless configurations
- Third-party water extractives test results
- ISO 9001 quality management certification for the factory
Common Sizing for Potable Tanks
WRAS-approved GRP tanks are commonly supplied in 5,000L, 10,000L, and 30,000L configurations. Modular sectional design allows custom dimensions to fit plant rooms, rooftops, and basement installations. For larger municipal projects, capacities up to 500 m³ are achievable with bolted panel assembly.
Need a WRAS-Certified Tank?
YATAI GROUP manufactures WRAS-approved FRP/GRP potable water tanks with full material documentation for export to UK, EU, and global markets.
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