Full retention separators treat the full flow that can be delivered by the drainage system, which is normally equivalent to the flow generated by a rainfall intensity of 65mm/hr. On large sites, some short term flooding may be an acceptable means of limiting the flow rate and hence the size of full retention systems.
Environment Agency PPG3 Guidelines stipulate that all separators must be fitted with a robust system to provide an audible and visual alarm if the oil level becomes too high. We strongly recommend that you purchase the Darcy Indoor Oil Alarm or the Darcy Outdoor Oil Alarm alongside this item, and it will be delivered with the separator ready to wire in.
Features and Benefits
- Light and easy to install
- Inclusive of silt storage volume
- Fitted inlet/outlet connectors
- Vent points within necks
- Extension access shafts for deep inverts
- Maintenance from ground level
- GRP or rotomoulded construction (rotomoulded for NSFP003 and NSFP006)
To specify a nominal size bypass separator, the following information is needed:
- The calculated flow rate for the drainage area served. Our designs are based on the assumption that any interconnecting pipework fitted elsewhere on site does not impede flow into or out of the separator and that the flow is not pumped.
- The drain invert inlet depth.
- Pipework type, size and orientation.