Electrical installation safety: Electrical installations, if not properly constructed and operated, can pose a danger to people and property. For this reason, precise safety regulations must be followed, both in the design and implementation as well as in the use and maintenance of the installations.
In this article, we will look in detail at the main safety rules to ensure that an electrical system is built in a skilful manner and can be used without risk to those who use it and to the places where it is installed. (we also wrote an article on home electrical safety)
The design phase of an electrical installation is very delicate because it is at this stage that all the characteristics and components of the structure are defined. It is, therefore, essential that the design be entrusted to qualified professionals and that it strictly follows the relevant technical standards.
In particular, the project must:
- Be prepared by a licensed professional, such as an electrical engineer or engineer.
- Comply with the relevant CEI (Italian Electrotechnical Committee) standards for the type of installation.
- Provide for the use of materials and components that are certified and comply with safety standards.
- Correctly size conductor cross-sections, circuit breaker ratings, and system power.
- Divide the system into separate circuits to handle loads and protections optimally.
- Provide adequate protection devices against short circuits, overloads, and contact voltages.
A well-done design is the essential basis for making a safe and efficient plant.
Realization of the plant
In the practical implementation phase of the system, the installation must be carried out in a professional manner in full compliance with the design and safety regulations.
The main aspects to consider are:
- Use of materials and components that comply with standards and are certified.
- Correct installation of piping, boxes, switches, sockets and every element of the installation.
- Laying of cables in compliance with the permissible capacities for each section.
- Correct tightening of screws, terminals, and connections.
- Clear identification of each component and cable according to the wiring diagram.
- Checks for continuity of conductors, insulation and protections.
- Final testing to ascertain compliance with design and technical standards.
Also, at this stage, it is advisable to rely on specialized and qualified personnel who can certify the correct execution of the work.
The electrical panel, containing all control and protection devices, is a fundamental element for safety purposes.
To ensure compliance with standards, the switchboard must:
- Be of adequate size to contain all necessary components.
- Have an IP rating appropriate for the installation environment.
- Have all components clearly identified with nameplates or diagrams.
- Be equipped with circuit breakers or residual current circuit breakers for protection against short circuits and indirect contacts.
- Have a main switch and circuit breakers for individual circuits.
- Ensure that live parts are not accessible without the use of keys or tools.
- Be properly grounded with protective and grounding conductors.
- Provide surge arresters if the installation is subject to lightning strikes.
Grounding is one of the most critical aspects of ensuring protection from indirect contacts, which occur when we come into contact with live metal masses due to a fault.
Therefore, it is essential to:
- Make the grounding system according to the relevant standards, with appropriate earth electrodes and conductors.
- Connect all ground and extraneous masses (water pipes, gas, etc.) to the grounding system.
- Ensure continuity of protective and grounding conductors to the system grounds.
- Perform periodic measurements of the earth resistance value, which must be lower than that stipulated in CEI standards.
- If necessary, install an earth leakage circuit breaker to protect against indirect contacts.
In order to maintain a good level of safety over time, it is necessary to carry out regular routine and extraordinary maintenance of the plant.
In particular, it is good to:
- Perform routine maintenance every year or every two years to check tightening, operation of protective devices, and state of preservation.
- Perform more extensive extraordinary maintenance every 5-10 years with instrumental tests to check insulation, fault currents, etc.
- Replace thermal-magnetic and differential protection devices periodically, according to the manufacturer’s instructions.
- Repair any deficiencies found during periodic inspections.
- Have work performed by qualified personnel.
- Keep a record of maintenance performed.
Certifications and declarations of conformity
Finally, to ensure the full application of safety regulations, it is mandatory that the electrical system be:
- Subject to the declaration of conformity issued by the installer, certifying compliance with all applicable standards in the implementation of the installation.
- Covered, if necessary, by the relevant certificates of qualification of installers recognized by the Chamber of Commerce.
- Covered for systems with power greater than 6 kW by the declaration of conformity issued by the ASL/ARPA following verification.
- Accompanied by the design and test certificate for more complex installations.
Therefore, constructing a compliant, safe and efficient electrical system requires compliance with precise provisions at every stage: design entrusted to licensed technicians, choice of certified materials, professional execution, installation of appropriate protective devices, efficient grounding, and periodic maintenance.
In addition, it is essential to certify the installation’s compliance through declarations of conformity, certificates and tests. Only with strict enforcement of all technical standards in the industry can the safety of those using an electrical system be ensured and the risk of fire or electrocution prevented.