WS007564A
Figure 6: Bracing and shoring
WS004325A
Figure 7: Shield box
• Regularly check the walls of an excavation or trench for cracks, bulges and spalling.
Check the shoring for signs of distress, especially after a rainstorm.
• Do not work in an excavation that is filled or partially filled with water. Remove personnel
from the excavation during a rainstorm, and inspect the excavation carefully before re-
entry.
• Do not store excavated material and equipment along the edge of the trench or
excavation. Do not drive or park vehicles along the edge of an excavation.
4.1.3 Inspect the work area before permit-required hot work
WARNING: Explosion/Fire Hazard
Before starting any permit-required hot work such as welding, gas cutting, grinding, or using
electrical handtools, do the following: 1. Check the explosion risk. 2. Provide sufficient
ventilation.
4.2 Installing the unit
• The contractor is responsible for ensuring that the installation follows the local regulations
and EN 976-2:1997.
• The unit must be installed underground, outside of the building.
• Dimensions in installation figures must be regarded as minimum dimensions.
4.2.1 Prepare the site
• Check that the following requirements are complied with:
– The excavation method of the pit must be adapted to the current soil conditions.
Considerations include slope stability and possible water drainage.
– Complicated soil conditions must be investigated by a geotechnical engineer.
• If the unit is installed in filled material of stony material, silt and clay, or in organic soil,
attach a separating layer of geotextile to the pit walls and bottom before backfilling and
compaction.
The geotextile prevents any material transportation from the backfill material into the soil.
• Refer to EN 976-2:1987 for demands on the quality of geotextile and installation method.
• Excavate in accordance with the minimum values.
Table 3: Approximate minimum diameter of excavation
Top version
Ø (mm)
50
1500
65
1900
80
2300
100S
2700
4 Installation
Flygt Top Installation, Operation, and Maintenance Manual
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