Penetrations must be waterproofed against water pressure as a matter of course, by using standard systems and/or certified products, for example with sleeve tubes and annular waterproofs, flange pipes with rigid pipe connections or core drills with medium pipes and annular waterproofs.

7.3.3 Responsibilities

When deciding on a white tank, everyone involved, and in particular those involved in the design, plus the client and any contractors already involved when the design stage starts, must be familiar with the design principles involved in a white tank. All findings and decisions required under the WU guidelines in terms of design, implementation and quality assurance must be recorded. All those involved must work together. Competences and responsibilities must be laid down and recorded in writing, clearly and unambiguously, before starting work.