Standard Plumbing Works QA/QC Site Inspection Checklist

🚰 Standard Plumbing & PHE Works QA/QC Inspection Checklist

General Quality Assurance & Quality Control Protocol for Water Supply, Drainage, Rainwater & Sanitation Systems

📌 Stage-I: Pre-Execution & Material Approval Stage

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  Sample & Technical Approval: Verify that all plumbing pipes (CPVC, UPVC, PPR, DI, GI), fittings, valves, water meters, and pumps have approved samples and technical datasheets. Standard Specs
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  Manufacturer Test Certificates (MTC): Verify MTC and pressure rating certificates for pipes, fittings, and valves prior to site installation.
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  Approved Coordination Layouts: Ensure plumbing shop drawings showing pipe shaft routes, sleeve penetrations, slope angles, and invert levels are approved. Design Norms
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  Safe Storage & Material Handling: Confirm plastic pipes (CPVC/UPVC) are stored flat under covered shade to prevent UV degradation, and pipe end caps are intact.

💧 Stage-II: Water Supply & Distribution Network

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  Piping Alignment & Support Spacing: Inspect pipe routing, alignment, solvent cement/heat fusion joints, and proper pipe clamp support distances. Plumbing Norms
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  Hydrostatic Pressure Testing: Conduct hydrostatic pressure test on water supply mains at 1.5 times working pressure (minimum 10 kg/cm²) for 24 hours without leakage. Testing Specs
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  Thermal Insulation & Cladding: Inspect hot water piping insulation thickness and protective aluminum/PVC cladding on exposed outdoor pipe shafts.
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  Overhead & Underground Water Tanks: Verify food-grade waterproof lining, air vent mesh screens, overflow pipe positioning, and automatic level controller probes.

🚽 Stage-III: Drainage, Soil, Waste & Vent Systems

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  Gradient & Slope Verification: Verify minimum required pipe gradients (e.g., 1:40 to 1:100) for soil and waste lines to ensure self-cleansing velocity. Drainage Norms
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  Water Fill & Smoke Testing: Conduct water head test (filling vertical stacks up to 3m height) or smoke/air testing to confirm zero leakage in joints.
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  Vent Pipe Cowls & Water Seals: Ensure proper vent pipe extension above roof level with wire cowls, and verify deep-water seal (minimum 50mm) in floor traps. Sanitation Specs
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  Inspection Chambers & Gully Traps: Inspect benching inside manholes, watertight chamber covers, drop connections, and gully trap seals.

🌧️ Stage-IV: Rainwater Harvesting & Storm Water Drainage

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  Roof Outlet Grates & Rainwater Pipes: Verify cast iron / domed gratings on roof outlets, expansion joints on vertical downspouts, and sturdy pipe clamps. Storm Water Norms
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  First-Flush Diverter & Desilting Tank: Inspect first-flush diverter arrangement and desilting chamber media before rainwater enters recharge pits.
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  Rainwater Recharge Pit Construction: Verify gravel/filter sand media layers, perforated casing pipe depth, and overflow arrangement to storm drains.
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  Submersible Sump Pumps: Test dual submersible sump pumps (duty/standby) with float switches in basement drainage pits.

🛠️ Stage-V: Testing, Flushing, Commissioning & Handover

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  Flushing & Disinfection (Chlorination): Flush water supply lines and perform chlorination (50 ppm chlorine solution for 24 hours) prior to domestic use. Hygiene Standards
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  Pressure & Flow Check at Fixtures: Verify dynamic water pressure and flow rates at faucets, showers, and flush valves across top and bottom floors.
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  Hydro-Pneumatic System Testing: Calibrate pressure transducers, dry-run protection, and automatic pump switching on the transfer/booster pumps.
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  As-Built Drawings & Handover: Compile signed testing & inspection certificates, water quality test reports, As-Built drawings, and O&M manuals.

💡 General Engineering Note: This checklist provides standard Quality Assurance (QA) and Quality Control (QC) parameters commonly followed in public health engineering, water distribution, drainage, and plumbing execution for modern residential, commercial, and industrial construction.