Electrical hazards at the workplace range from mild electric shocks and burns to more severe injuries and health complications that result from brief yet powerful arc flashes. Electric arc flashes and blasts are capable of causing severe burns. The extreme heat and acoustic waves can damage vision, hearing or even trigger concussion and memory loss. The impact of such blasts can prove fatal, especially when workers are thrown off elevated work platforms, scaffoldings or ladders.
Employers can ensure safety of workers, who are prone to electric arc risks as a part of the their daily jobs, by opting for suitable personal protective equipment, arc-rated flame retardant clothing, accessories and gear after a thorough assessment of the hazard and its severity.
There are different alternatives and approaches that can help ensure electric arc protection. Having workers suited up for the entire shift in arc rated clothing that offers maximum protection, though ideal, does not seem quite practical, unless the job so demands.
Layered protection has by far proved to be a more pocket-friendly and effective solution, especially where workers are expected to face electrical hazards of different categories or severities during the course of their daily shifts. Electric arcs may be just one of the many risks these workers face that too when on specific jobs in hazard risk categories (HRC) of 2 to 4.
|ProGARM 6100 Arc Coverall
+ 5200 Polo Shirt
= ARC 3, Class 2
Class 2 protection to Torso only
|Roots RO25100, RO25120 Underwear
+ RO2517 Waterproof Bib and Parka
= ARC 4, 48.9 cal/cm²
Effectiveness of Layered Protection Systems
Layered clothing helps ensure better or enhanced levels of arc flash protection, when workers are constantly switching between jobs with different HRCs. All they need to do is find a suitable arc-rated outerwear to wear over an Arc Rated (AR) uniform or clothing they are already wearing, before heading out to address a high-risk problem.
Several tests stand testimony to the fact that arc-rated layered protective garments of different calorific ratings offer the same level, if not better levels of protection than one single protective clothing unit of a higher rating.
For example, an arc-rated 7-oz coverall with a calorific rating of 8.7 cal/cm² (HRC 2) worn over an arc-rated 7-oz, 8.7 Cal/cm² Polo shirt of the same rating reportedly achieved the necessary protection needed for an HRC 3 hazard.
Results are quite encouraging as they go to prove that several layers of arc-flash rated protected clothing can offer same levels of protection as an HRC Arc flash switching suit, which probably is relatively heavier to carry and use on a regular basis.
The Multi-Layer Advantage
Aiming to achieve protection through layers for high-risk jobs proves beneficial in several ways:
- The flexibility and comfort of layered protective garments ensure workers do not move to a higher risk area without the necessary PPE, for it has often been observed that the time and effort needed to find and don a bulky and heavy PPE itself is a deterrent that affects compliance. This alternative surely leaves no room for excuses to skip additional protection.
- The approach saves workers a considerable amount of time and effort spent on locating and slipping into the specialised protective suit say for HRC 3 or 4, each time they address a high-risk job.
- Once clothed in an essential Arc Flash Rated AR (under)garment that offers basic level of protection, workers definitely find it more comfortable to get in and out of additional arc-rated protective clothing that provide maximum protection for the next task at hand.
- Layered protective clothing also proves a wise investment for employers as it helps them stay compliant with safety standards by not only guaranteeing adequate protection against electric arc flashes and blasts, but also promoting worker involvement and participation in the safety initiative.
Apart from the above mentioned tangible advantages of layered protection against electric arcs, there is one key imperceptible benefit as well.
The air trapped between multiple layers of loose protective clothing doubles up as an effective buffer, augmenting the level of safety and resistance to heat and flames. The degree of insulation, thus, added varies based on the type, texture and weight of the material and tightness of the garment, but cannot be accurately measured.
Electric Arc Protection – Things to Note
It is a well-known fact that electric arc hazards can cause severe burns and other fatal injuries. The right arc-rated (AR) clothing and PPE, including gloves, footwear, shields, hard hats and other accessories are mandatory to ensure head-to-toe protection for high risk category jobs.
As arc flashes are capable of reaching under multiple layers of clothing, it is imperative to ensure undergarments are resistant to Arc flash’s and do not melt when exposed to high temperature. Similarly the outer wear, which first bears the impact of an electric arc, must be Arc Rated as well.
The non-AR daily wear over the protective clothing is bound to catch fire in the event of an arc flash, eventually raising the surface temperature of the underlying protective garment and rendering it ineffective or inadequate in the process.
Thus, appropriate arc-rated AR undergarments and outerwear should necessarily figure as part of the PPE for layered protection to work as intended.
Ensuring NFPA 70E compliance often proves to be massive, yet a mandatory expense that needs serious considerations on the part of the employer. While it is important to extend the highest level of protection money can buy in the form of PPE and FR clothing, the comfort and operational efficiency of the worker holds the key to compliance.
Partnering with a reliable, trustworthy PPE supplier with thorough knowledge of IEC/OSHA standards will help employers implement a cost-effective and fully compliant PPE program. In consultation with their PPE suppliers, employers can opt for an assorted mix of arc-rated layered clothing or full HRC suits, equipment and other accessories that best help counter workplace-specific electric arc hazards in a speedy and effective manner, without compromising the physical ease, functional ability or agility of the wearer.