Arc Flash Studies & Assessments

• What is an Arc Flash?
  An arc flash occurs when a short-circuit is made in an electrical power distribution system and an electrical current makes a jump through the air. This arcing is similar to lightning and poses a hazard to electrical workers that is often not considered. For more detailed information, see the ‘What is arc flash (Click here)’ page.

• Why should I be worried about arc flash hazards? Isn’t this only a concern in the United States?
  Arc flash risk exists anywhere people are working near energised equipment, and sometimes it is simply unavoidable to be working near a live conductor. In Europe, there’s currently no legal obligation to consider it, but current standards are perfectly suited to include arc flash hazards in a work safety program.

• Should I buy arc-rated PPE without doing my research?
  No, buying PPE to protect personnel without carrying out an arc flash energy study is not the solution to the arc flash hazard issue. The arc energy study/assessment determines energy levels around the network and determines what arc flash-rated PPE should be worn to protect against second-degree burns.

• What can I do to prevent arc flash occurrences?
  The hazard can be calculated, reduced, and mitigated. Once calculated, there are plenty of measures that can be taken to either reduce or entirely remove the hazard. The remaining hazard can be mitigated through PPE.

Damaged Buildings:
Evaluate the structural integrity of your sites and assess buildings for signs of damage, including leaky roofs, damaged fan meshes, broken windows, and misaligned doors.

PPE Compliance and Signage:
Ensure compliance with minimum PPE requirements, contributing to a safer working environment. Emphasise the importance of clear PPE signage at switchroom and substation entrances and adhere to Electricity at Work Act (EWA) guidelines to avoid legal issues.

SLD of Electrical Distribution:
These should be updated regularly, and the revised single-line diagrams (SLDs) should be displayed prominently within the building, ideally near control and switchgear areas.

Protection Settings and Demarcation:
Overly tolerant settings and demarcation errors are common issues found in older systems. It is important to identify and rectify these issues to enhance the overall protection and safety of your assets.

Rusted Switchgear:
Issues such as rusted switchgear and chipped paint increase the risk of moisture infiltration.

Earth Rubberised Matting:
It is important to ensure that each switchgear and control panel is equipped with well-maintained and rubberised insulation strip flooring to prevent potential trip hazards. This, along with the use of appropriate safety footwear, is vital when exposed to live cables.

Rodent Activity:
Rodents and wild animals are common causes of arc flash incidents. Once they find an entry, they tend to seek out the warmest locations, the switchpanels.

Internal Moisture:
Internal moisture can become a common occurrence, especially in situations with varied ambient and external temperatures.

New to Site:
To provide safe and secure isolations, knowledge and experience particular to the location are essential. If you are not familiar with the settings, it is best for HV and LV engineers to conduct a thorough investigation. When using remote isolations, proceed with caution and make sure the appropriate breaker is present for safety. Always use appropriate tag & lock features to verify and certify that the system is dormant before moving forward.

No Recent Switching / Isolation History:
It’s important to consider that no prior switching has occurred, or it could be that the correct safe switching procedures have not been followed.

Blog Articles

• 5 Ways You Can Reduce the Risk of Arc Flash
• How Often is an Arc Flash Study Required?
• What Are The Key Components Of An Arc Flash Study?

Case Studies

• Arc Flash & Power System Studies: African Data Centre
• Energy-from-Waste Plants (UK): Arc Flash and Protection Coordination Studies

Guides

• Arc Flash Hazard Compliance, Risk Assessment & Mitigation

Understanding and addressing the following typical oversights is vital to ensuring safe and efficient operations:

1. Absence of a Distribution Single Line Diagram (SLD) Display:
   Failure to sufficiently display distribution SLDs can deny personnel quick access to critical information and hinder their ability to understand the system layout. This increases the risk of incorrect actions during maintenance and emergencies.
2. Missing Energy Level Signage and PPE Category Identification:
   The lack of clearly visible signage indicating the appropriate levels of PPE can lead to inadequate protection measures, jeopardising the safety of your personnel.
3. Unplanned Recovery for Planned Outages:
   Unexpected energy sources may be produced by implementing unplanned recovery operations during scheduled outages, increasing the possibility of arc flash accidents. To avoid unforeseen results, planned processes must be strictly followed.
4. Misidentifying Flame Retardant as Arc Flash Protection PPE:
   Safety depends on using the right PPE and identifying it. Confusing appropriate arc flash protection with flame-retardant apparel PPE may lead to insufficient personal protection, putting workers in danger during an arc flash incident.
5. Absence or Unsigned Switching Statement:
   Miscommunication and inappropriate actions during switching operations are increased when there is no documented switching statement or when the switching statement is unsigned. Ensuring correct and safe processes requires a switching statement that is fully prepared and authorised.
6. Pre-outage walkthrough/simulation of switching:
   Potential risks may go unnoticed if pre-outage walkthroughs or changeover procedure simulations are neglected. By recognising and resolving hazards before actual operations, these actions are critical to improving overall safety.
7. No safety person during procedures:
   Conducting electrical procedures without the presence of a designated safety person increases the risk of accidents. Having a dedicated safety person is crucial for monitoring and responding to unexpected events during operations.
8. Failure to prove and confirm dead by SAP:
   Neglecting the essential step of confirming and proving a system is dead by a Senior Authorized Person (SAP) introduces the risk of working on energised equipment. This oversight can lead to serious consequences and must be diligently addressed during electrical work.

9. Inefficient Tag/Lockout System, Register, and Equipment:
   An ineffective tag/lockout system, an incomplete register, or faulty equipment compromises the ability to secure and isolate electrical systems adequately. Ensuring the efficiency and accuracy of these safety measures is vital for preventing inadvertent energisation and arc flash incidents.

Failure to address these oversights can lead to increased safety risks, operational inefficiencies, emergency response delays, compliance issues, and increased repair costs.

1. Lack of caution:
   Not adhering to safety procedures, inadequate training, or complacency during electrical work can lead to costly errors that endanger your staff and equipment.
2. Ageing or damaged insulation on a conductor or busbar:
   As time passes, insulation around conductors or busbars can begin to degrade due to wear and tear, other environmental factors, or physical damage. This can compromise the insulation’s ability to contain electrical currents and increase the risk of an arc flash incident.
3. Exposed live components:
   Failure to enclose or shield live electrical components can expose them to external factors. Proper containment and insulation are vital in preventing arc flash incidents and short circuits.
4. Loose electrical connections:
   Loose and/or improperly tightened electrical connections can cause resistance and potentially lead to arcing. This can result from poor workmanship or vibrations in the electrical system.
5. Poorly maintained switches and circuit breakers:
   Circuit breakers and switches that are worn out or broken might be the consequence of poor maintenance. When these parts aren’t working right, they are unable to prevent a malfunction, which makes an arc flash more likely.
6. Incorrect switching, isolations, or switching statements:
   Executing incorrect switching operations or isolation procedures can create unexpected electrical paths and cause arcing. A lack of sufficient understanding or a failure to follow proper protocols can contribute to dangerous electrical discharges.
7. Water, liquid, and condensation near electrical equipment:
   Moisture can compromise the insulation properties of materials and increase the risk of arcing. Water or dampness near electrical equipment can lead to short circuits and create a conducive environment for arc flash incidents.
8. Tools left unattended upon HV or LV cables or busbars:
   Tools that are left near live cables or busbars can inadvertently create a conductive path, leading to unintentional contact and potential arc flashes. Effective tool management and adherence to health and safety standards are essential.
9. Static electricity:
   The build-up and release of static electricity can cause an arc flash in settings with insufficient static management measures. This issue is especially important for sectors whose procedures produce static electricity.
10. Damaged tools & equipment:
    The risk of sparks or electrical faults increases when damaged tools or equipment are used. Performing routine maintenance and equipment inspections can help reduce the likelihood of these occurrences.