This article is about Drain and Toe Walls for Surface Drainage and Technical Requirement in commercial buildings, plants and refinery projects related to Plumbing Engineering System as per international codes and standards.
Drain and Toe Walls for Surface Drainage
Drains
- Drains shall run to the nearest catch basin or manhole through a sealed connection at the catch basin or at the manhole.
- The horizontal distance between the drain opening and the catch basin or the manhole shall not exceed 15 meters.
- All drain points shall have an air gap between the point of discharge and the point of collection into the oily water sewer system
- The lip of a drain funnel shall be elevated 80 mm above the ground to prevent surface drainage from entering the drain.
Note: RTR material may be used for drain funnel.” - Drains from laboratory sinks, analyzer houses, or other facilities where oil releases are possible shall be connected through a liquid trap seal connection to a vented manhole of the oily water sewer system or to a vented holding tank.
- Holding tanks shall be provided with electronic or manual means of gauging contents.
Toe Walls
- Toe walls shall be provided at hydrocarbon pump bases if boiling point of hydrocarbons exceed 5°C at atmospheric pressure, at oil-filled transformers, at furnaces burning liquid fuels, and at furnaces with flammable liquid in tubes. Note: Verify Boiling Point (Design)
- Surface area within toe walls shall be graded to direct effluent to the nearest catch basin, and to divert surface flow safely away from equipment. Toe walls are not designed to contain effluent.
- Toe walls shall have a minimum height of 150 mm.
International Codes and Standard References for Drain and Toe Walls for Surface Drainage
SAES-S-020 Industrial Drainage and Sewers.
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