Service networks in construction sites: possible risks
In some networks, the building industry and technical services may constitute a high hazard. Preventive measures and instructions for employees in the presence of sewage networks, water distribution networks, electricity, gas and other energy sources.
In the database of bibliographic records contained in the "Risk assessment in building construction" - a collaboration between the Territorial Joint Committee and the Province of Turin (Torino CPT) and the 'INAIL Piedmont - several tabs are dedicated to risks due to networks and technical services in the yard or around the area.
We present briefly some, a reading of the detailed information, consult the original documents for a more comprehensive collection of information on possible preventive measures.
Recall that construction companies can refer to these cards for the management of safety in the workplace, and adapting to different environments and situations specific to the establishment, for the drafting of DVRe security plans.
Distribution networks of electricity
In the construction sector the presence of live power lines affecting the site "is always a high source of danger." And "guards, alarms, minimum distances from the work of the temporary works and by lifting sometimes not enough to prevent injuries."
To promote prevention are some guidelines for those involved:
- "The utmost care is required during the whole execution of the work and involvement of the staff of the site and of all those who have access, even occasionally in the work;
- Particular attention should be paid during transport by mechanical means and the lifting of particularly voluminous materials and use of equipment with movable arms of considerable size (cranes, concrete pumps, etc.).
- The assembly and disassembly of metal structures in the vicinity of power lines under tensionedevono be avoided, it is always necessary to provide those shall operate these lines to isolation and protection of the same or to temporarily put out of service;
- Frequently in towns served by trams or trolleybuses occurs the need to allestireponteggi metal frieze in the buildings, which, compared to traction lines are almost always found at distances smaller than the 'safe distances' allowed'. In particular, it is necessary "to carry out the assembly of scaffolding and protective structures (valances, screens, nets), until completion of the danger zone, line disabled;
- In the presence of electrical wires in tension or in underground tunnel should be provided accurate information and instructions that involve building personnel and all suppliers in order to avoid the execution of excavations or the simple insertion of elements in the soil in the vicinity of the cables themselves. Where are carried out excavation work that interfere with live lines, the operations must be carried out prior to the shut-off of the lines and safety of 'power line. During the work no person has to remain in the ground in the vicinity of mechanical means of excavation and movement of materials. "
Gas distribution networks
It must always be ascertained, "the presence of elements of gas distribution networks that can interfere with the yard." In the case must be promptly warned the operators of such networks to "agree on the essential security measures to be taken before work and during the development of the work" and to "detect and report the path to the surface and the depth of elements" . It is thus possible to determine "mode of execution of the work such as to avoid the occurrence of dangerous situations for both the work to be performed, and to the exercise of the networks." In the case of excavation work that interfere with these networks "is necessary to provide systems for protection and support of the pipes laid bare, in order to avoid damage of the same and to the consequent risk."
Here are some instructions for employees.
"Having ascertained the presence of gas networks that interfere with the work you need to proceed with caution neilavori excavation, reducing vibration and shaking of the ground and proceeding by successive layers, avoiding costly landslide which causes the boundary. When such works directly interfere with the networks it is necessary to expose the pipes manually proceeding to the safety of the pipe concerned. The work must be carried out under the direct supervision of an officer. During the work must be no smoking or open flames. If you can not disable the network section concerned is necessary to activate a system of direct and immediate communication with the concession operator for the suspension of the network in case of danger. During the execution of the work you need to check, even instrumentally, the presence of a gas leak. "
Distribution networks of water
Even in this case must be ascertained "the presence of elements of distribution networks of water and, if applicable, must be provided to detect and report in the path surface and depth. In the case of excavation dilavori that may interfere with or pass through these networks is necessary to provide protection systems and support of the pipes, in order to avoid damage and the associated risks. "
The employees remember that "in the presence of water networks that interfere with the excavation work is necessary to proceed with caution, limiting the actions of disruption to the contour of the same networks (vibration, shaking, landslides). If the work interfere directly with these networks it is necessary to strip and security lines, moving manually and under the direct supervision of unpreposto. During the execution of the above stages of work is necessary to organize the ready power supply to part of the network affected by the works, to be activated in case of need. "
Sewerage
It is necessary to ascertain the presence of sewage systems for both active and no longer used. Especially during the excavation work, "the presence, even to the boundary, of sewers must be known, since it is always an important variable with respect to the consistency and stability of the walls of the excavation and for the presence of the backfill soil, both for the possible sudden formation of voids in the soil (in the case of typical vetuste drains discontinued), both for the presence of possible seepage of water or flooding due to cracking or yielding of the walls adjacent to where earthworks. "
Some instructions for employees:
- "In the excavation work to be performed in the vicinity of sewer you should always proceed with caution, the walls of the excavation and armor at these networks need to be kept under control by unpreposto;
- When the distance between the open excavation and sewerage existing measures does not ensure the stability of the third wall is necessary to expose the pipeline and protect it against damage. "
Other energy
The distribution networks of other energy "may be aerial or underground and in general may not pose specific risks to the neighboring works, but can be damaged by the same work (demolition, excavation, installation of structures and temporary works, plant). This being is always necessary to secure them before starting work and proceed with caution during the execution of the works, in the same manner already mentioned for the work near or interfering with the networks of electricity, gas, water and sewerage. "
Finally, remember that all boards, in addition to indicating the technical preventive measures and instructions for employees, report the procedures to be applied in the event of an emergency, the personal protective equipment to be taken and offer guidance on the training of workers and on signs from installed at access to the site and sources of risk.
04/02/2011
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Translated via software
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Source:
Italian version of ReteArchitetti.it