Inputs
Chamber dimensions per Water UK SSG/DCG / CIRIA guidance.
Project Information
Adoptable: man-entry chambers to Water UK DCG Table B.1 (min 1200 mm ID). Private: Part H access hierarchy (access fitting / IC / shallow chamber).
Plastic inspection chambers are for rodding / visual inspection only (no person entry). To 1.2 m to invert they take a standard cover; beyond 1.2 m (to ~3 m) they stay non-entry with a restricted-access cover (clear opening ≤350 mm, to deter entry — AD H Table 11). A person-entry manhole (with HSE L101 / CDM 2015 confined-space procedures) is required only beyond ~3 m or where person entry is specifically designed.
Method: Plastic inspection chambers sized per Approved Document H Table 11 / manufacturer schedules (BS EN 13598-1 for shallow chambers to 1.25 m; BS EN 13598-2 for deeper chambers). Adoptable plastic manholes (BS EN 13598-2) up to DN 1000. Precast concrete chambers per SSG/DCG Appendix B / BS EN 1917 & BS 5911-3: base size from largest pipe DN and invert depth, with branch allowance and confined-space working room.
Recommended Chamber
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