Electrical Power ARC-FLASH Review

The Risk
The employer is responsible for the safety of his personnel and shall define electrical safety requirements for employee and contractor's work places that are necessary for the practical safeguarding of employees during activities such as the installation, operation, and maintenance.
Switchgear in most operational environments, when properly maintained, performs in service without fail for a number of years. Nevertheless, over the years the number of reported cases of serious burns and fatalities due to thermal energy associated with arcing faults has increased.
An arc fault occurs when electrical clearances are reduced or compromised. Electrical systems are also subject to modifications over time. Changes such as additional equipment or modification can affect the level of arc flash energy.
There is definitely a real risk that needs to be addressed with the types of non-internal arc protected switchgears that may be installed at your site. In event of a fault, an explosion of hot gases can occur which can result in severe consequences, including death, for personnel positioned close to the fault.
One might expect that such failures may be related to the age of the equipment. However, experience has shown that this is not only an equipment ageing related problem. Faults can occur in new as well as old equipment and have a strong correlation with the maintenance or commissioning works. These tends to be associated with 'abnormal' or 'unusual' activities like incorrect operation due to not respecting, or misunderstanding, the procedures, insufficient training, materials left behind after maintenance etc., rather than routine switching.
The Process
Especially maturing facilities including Higg and Low Voltage switchgear need to be assessed on their arc-proof capabilities and limit the exposure of electrical staff to arc-flash energy levels during operational activities. Through a field survey and a subsequent study of the findings, the potential risk to staff is recorded based on which a report of mitigating recommendations is issued to the client. During the field survey, awareness training on the arc-flash risk is provided to operational staff.

• Assessing arc flash hazard levels based on IEEE-1584 and NFPA-70E;
• Educating staff on the risks related to arcing faults and train them to carry out such assessment themselves in future;
• Quantifying the risks posed to operators for various switchgear operations based on AM matrix ;
• Helping to reduce these levels of risk through mitigation strategies (other than Personnel Protection Equipment);
• Suggesting the arc-flash level to which PPE shall be resistant to protect your staff against risks during a limited number of special activities which cannot be mitigated in a different way.

The Benefits
The deliverable of the arc-flash review is a comprehensive report with all the arc-flash energy levels at the various High and Low Voltage switchgear as well as the recommended measures that need to be taken to mitigate the risks or reduce them to ALARP. This provides asset owners with the necessary documentation to assist them in the electrical safeguarding of their electrical personnel at the workplace. The Team Depending on the size and extent of your facilities, a team of usually two specialist consultants will carry out the site survey, collect crucial data, witness key operational activities and provide training to staff. The report of findings is validated by an independent principal consultant prior to issue.
The Timing
An arc-flash review of an electrical system is normally applied to existing installations. It is ideal if the survey is combined with a TAM activity, enabling the switchgear to be isolated and panels opened, but this is not a must. Optimal collection of applicable documentation prior to the field survey will facilitate focus on work at site.