Arc flash incidents are a critical safety concern in the construction industry, posing severe risks to workers. Selecting appropriate arc flash clothing is vital for enhancing safety. 

Arc Flash Defined

An arc flash is an explosive electrical discharge through air to ground or another voltage phase, capable of reaching temperatures up to 20,000°C. The force of an arc blast can hurl workers across spaces, while the intense light and sound can cause severe sensory injuries, underscoring the necessity for proper protective clothing.

Here are 10 crucial aspects to understand:

1. Defining Arc Flash

An arc flash is a type of electrical explosion, or “flashover,” resulting from an arcing fault between electrical conductors. It releases intense energy capable of causing fatalities, with the HSE noting approximately 1,000 workplace electrical incidents reported annually in the UK.

2. The Hazard of Arc Flash Explosions

Arc flash incidents can generate temperatures exceeding 20,000°C, potentially propelling workers across rooms, rupturing eardrums, causing permanent deafness or blindness, and emphasizing the necessity of arc flash protective clothing to mitigate burn risks.

3. Arc Flash Occurrence

Such incidents primarily occur when electricity jumps through the air between conductors, posing risks particularly in industries like rail, power generation, electrical, and utilities/construction, especially during excavation tasks.

4. Industry-Specific Risks

Workers in the rail, power generation, and utilities sectors face significant arc flash dangers due to the electrification of railways and the inherent risks in power generation and construction-related excavation work.

5. Regulatory Compliance: HSG47

The HSG47 guideline mandates arc flash workwear for tasks involving excavation, highlighting the risk of hitting underground electrical cables and the consequent arc flash hazard, emphasizing the role of protective clothing as a crucial last line of defense.

6. Protective Clothing Essentials

Effective protection against arc flash involves layering flame-resistant garments beneath arc-rated products. This combination significantly enhances safety, with the air between layers adding insulation and reducing ignition risks, necessitating certified arc flash clothing and accessories.

7. Undergarments Matter

The importance of appropriate undergarments, such as flame-resistant cotton underwear, is often overlooked. Synthetic materials can melt under arc flash conditions, causing severe burns, thus highlighting the need for specific flame-resistant base layers.

8. IEC 61482-2 Compliance

Arc flash protective clothing must meet the IEC 61482-2 standard, which sets benchmarks for protection against the thermal effects of arc flash. This includes the open arc test for Arc Thermal Performance Value (ATPV) and the box test for Class 1 and Class 2 protection levels.

9. Understanding Arc Flash Ratings

Protective clothing is assessed by its ATPV or ELIM rating, indicating the garment’s effectiveness in preventing second-degree burns. A higher ATPV rating suggests better protection, with ELIM indicating a garment’s ability to prevent burns altogether.

10. Distinguishing FR and Arc Flash Clothing

Not all flame-resistant (FR) clothing offers sufficient protection against arc flash, underscoring the need for arc-resistant garments specifically designed to shield against electrical arc hazards. High-quality arc flash clothing features inherently flame-retardant fabrics, anti-static properties, and ergonomic designs for safety and comfort.

Understanding Arc Flash Clothing Safety Standards: In depth

Arc flash incidents represent one of the gravest hazards in workplaces involving electrical systems or where excavation is taking place. For this reason construction sites can be high risk areas. To mitigate the risks associated with arc flashes, it’s imperative to adhere to specific safety standards for arc flash clothing. 

Key Safety Standards for Arc Flash Protection

IEC 61482-2: Essential for Arc Flash Safety

The cornerstone of arc flash protective clothing standards is IEC 61482-2. It ensures individuals working near electrical hazards are shielded from the extreme risks posed by arc flash explosions, integrating measures for both fabric and garment assessments to certify protection levels.

The Box Test Method: IEC 61482-1-2:2007

Superseding ENV 50354, the Box Test Method evaluates fabrics and finished garments against arc flash exposure, classifying protection into two levels:

Class 1 offers protection at 4 kA for 0.5 seconds, indicating a lower level of safeguarding.

Class 2, testing at 7 kA for 0.5 seconds, provides a higher protection level.

This method allows garments to achieve CE certification, denoting adherence to safety classifications based on test outcomes.

Open Arc Test Method: IEC 61482-1-1:2019

Facilitating precise protective garment specifications, the Open Arc Test Method assigns an Arc Thermal Protective Value (ATPV), guiding the selection of garments based on risk assessments and arc flash studies. Certification to this method assures a garment’s efficacy in preventing burns, based on ATPV ratings.

ATPV vs. ELIM: Quantifying Protection

ATPV (Arc Thermal Performance Value): Indicates a garment’s capacity to prevent second-degree burns, with a focus on achieving a balance between protection and wearability.

ELIM (Energy Limit Value): Represents the threshold at which arc flash clothing ensures zero percent chance of second-degree burns, emphasizing the importance of comprehensive protection in high-risk environments.

Complementary Standards for Comprehensive Safety

EN ISO 11612:2015

This standard outlines performance requirements for clothing designed to shield against heat and flame, covering various heat exposure scenarios from radiant and convective heat to molten metal splashes, ensuring broad protective measures for wearers.

EN ISO 14116:2015

Focusing on limited flame spread, EN ISO 14116:2015 targets protective clothing that reduces burn risks from brief flame contact, suitable for environments with minimal heat hazards.

EN ISO 11611:2015

Specific to welding and allied processes, this standard protects against molten metal splashes and arc radiation, catering to specialized industrial activities.

EN 1149-5:2018

Addressing electrostatic properties, EN 1149-5:2018 sets criteria for clothing that prevents incendiary discharges, critical for maintaining safety in environments with explosive or flammable materials.

The Role of Employers and Safety Suppliers

Employers bear the responsibility of equipping their workforce with arc flash clothing that meets or exceeds these standards, ensuring the safety of individuals operating in or around electrical hazards. For further information or advice please feel free to contact us at Workwear Gurus and we’d be happy to assist.