Install Pit BRG NBN-CON-GDE-1656 | Rev 1.0 | 02 APR 15 Owner: Lance Parkes - Standards & Field Practices, Construction Standards & Processes This build reference guide (BRG) provides a guide in relation to pit installation. It r eferences rules and guidelines guidelines from the following documents:
NBN-COO-P&D-490: Type 2.0 Architecture: Passive Network Design Rules
NBN-TE-CTO-483: NBN Co Conduit and Pit Network Deployment: Brownfields
NBN-TE-CTO-194: New Developments: Deployment of the NBN Co Conduit and Pit Network – Guidelines for Developers. Developers.
Note: Note:
Before and during this task ensure all applicable safety requirements are followed.
Do not deviate from the specifications provided, without prior approval from NBN. NBN.
Do not commence digging without first checking for other assets via the Dial Before You Dig website website or 1100 phone number.
Ensure a minimum separation of 1m from all poles excluding transformer poles. Ensure a minimum separation of 15m from any pad mounted transformer or pole with a transformer installed on it (EPR zone). Ensure a minimum separation of 1m from back of kerb where practical. Ensure a minimum separation of 3m from the property boundary for all pits i nstalled on corners. Ensure pit is aligned with the kerb in communications alignment. Do not install pit on an angle (as in photo).
Install Pit BRG
For Official Use Only NBN-CON-GDE-1656 | Rev 1.0
Excavation of Site
Excavate site to required size and depth. Excavate site larger than the pit to accommodate correct compaction methods – typically a minimum distance of 150mm beyond the outer wall of the pit is sufficient. Ensure that the excavated site allows for conduit to be installed at the correct depth.
Install Pit BRG
For Official Use Only NBN-CON-GDE-1656 | Rev 1.0
Pit Foundation
Ensure a foundation of sand, refined crushed rock, or stabilized sand is used to a depth of 100mm. Make the required alterations to the pit foundation in order to level out pit with ground surface level or pavement.
Install Pit BRG
For Official Use Only NBN-CON-GDE-1656 | Rev 1.0
Conduit Entries to Pits
Ensure the conduit entries are correct. Ensure the correct size hole saw is used for conduit entries to allow the bushes to be a tight fit into the pit. Ensure conduits are cut square and flush to interior wall of the pit with conduits inserted fully into the bush and PVC glued. Ensure entry/exit points at opposite ends of the pit are aligned in order for cabling to be hauled through easily.
Do not extend conduit too far into pit, at an angle or without a bush.
Note: the conduit example in the photo i s now a difficult rectification as there is a good chance the cable will be damaged and split bushes will be required.
Install Pit BRG
For Official Use Only NBN-CON-GDE-1656 | Rev 1.0
Do not misalign conduit entry and exit points as this could cause hauling issues.
Ensure the top of the entry f or the conduit is level with, or below, the minimum depth of cover required, i.e. 450mm for all street conduits. Ensure the bottom of the entry for the conduit is 50mm above the inside base of the pit to avoid infiltration of silt into the pit
Install Pit BRG
For Official Use Only NBN-CON-GDE-1656 | Rev 1.0
Back Filling
Contour the backfill material into the ribs in order to provide maximum strength and to maintain the pits structural integrity.
Use sand, refined crushed rock or stabilized sand as backfill material.
Do not allow the walls of the pit to warp during the backfilling process.
Ensure a non-mechanical hand operated compactor is used to hard-pack backfill. Compact in layers 150mm in depth or under. Use this process to fill t he whole excavation with allowance for final surface reinstatement.
P6, P8 and P9 pits came with two PVC cable bearers fitted into the interior of the pit, these bearers must be installed before back filling commences along with the gaskets.
Install Pit BRG
For Official Use Only NBN-CON-GDE-1656 | Rev 1.0
Ensure in grassed areas, backfill material stops within 50mm of the finished surface level and that top soil or turf is installed to the finished surface level (visible clumps of dirt, clay and rocks will not be acceptable). Alternatively allow for laying of pavement or temporary hard surface reinstatement. Check temporary hard surfaces reinstatement for trip hazards. Ensure all spoil and rubbish is removed at completion of pit installation. Incorrect backfilling methods will result soil subsidence around pits post installation causing safety issues All new NBN pits require NBN branded lids any new pits with Telstra infrastructure inside require Telstra lids
Install Pit BRG
For Official Use Only NBN-CON-GDE-1656 | Rev 1.0
Where possible, the installation of a pit in both pathway and verge or garden bed simultaneously should be avoided.
Install Pit BRG
For Official Use Only NBN-CON-GDE-1656 | Rev 1.0
Labelling
Label the NBN breakout conduit during installation. Label any breakout conduit that link Telstra pits to Telstra pits. Label and seal any breakout conduit that link Telstra pits to NBN pits. Do not wait until PC to label the conduit as returning later will take extra time and may be forgotten.
Install Pit BRG
For Official Use Only NBN-CON-GDE-1656 | Rev 1.0
Install Pit BRG
Update Documentation during Construction
Update the Construction Plan with red lines to reflect ‘as built’.
Prepare dilapidation reports with before and after photographs and addresses during construction. Do not wait until PC to update documentation as updating documentation during PC will take more time
This is not intended to be an exhaustive list of instructions – please see your site supervisor for more detailed information.
