Arc Flash Protection - Less than 10 Cal | Team Metron (2024)

FAQs

What is the Cal rating for arc flash protection? ›

These are the different arc flash levels of protection: Category 1 (4 cal/cm2) Category 2 (8cal/cm2) Category 3 (25 cal/cm2)

An Arc Flash typically releases between 5 to 30 calories and energies of 30 to 60 calories are not uncommon. Most Arc Flash injuries can be prevented if proper Flame Retardant (FR) PC & PPE is worn.

Required Clothing: Arc Rated Flash Suit Jacket and AR pant or AR coverall with minimum arc rating of 25 cal/cm. Required AR Face and Head Protection: Arc Rated Flash Suit Hood with minimum arc rating of 25 cal/cm.

PPE Category 4: Minimum Arc Rating 40 cal/cm

This category requires additional layers of clothing and typically includes: AR flash suit jacket and pants or AR coveralls with a minimum arc rating of 40 cal/cm.

Each arc flash coverall category then requires a minimum cal rating. For example, there are coveralls with arc flash 12 cal rating. It means that 12Cal/cm² is the minimum incident energy the coverall can absorb before it heats up and causes burns.

When you see an item that is marketed as a 40 cal arc flash suit, the number actually means that the suit is rated to protect against arc flashes with an incident heat energy level of up to 40 cal/cm2. At the TEN Group, we carry arc flash clothing rated between 8 cal/cm2 on the low end and 100 cal/cm2 on the high end.

CAL Rating: In this case, “CAL” refers to a more detailed, precise measure of protection, and is labeled in calories, or the units used to describe the force of an arc flash. For example, an article of clothing with a CAL rating of 8.1 would provide protection if an arc flash was 8.1 calories or less.

The amount of energy impressed on a surface, at a certain distance from the source, generated during an electri- cal arc event. One of the units used to measure incident energy is calories per centimeter squared (cal/cm2). Incident energy analysis.

A person must be exposed to a potential difference of 50 volts or more for a shock hazard to exist. A person might be exposed to hazards associated with an arcing fault even when the conductor is guarded. A guarded conductor protects a person from exposure to shock or electrocution but not to arc flash hazards.

The National Fire Protection Association (NFPA) 70E Standard is a comprehensive standard that provides detailed guidance instructions on administrative measures for controlling electrical shock and arc flash hazards in the workplace. It details how to protect workers from the heat of electric arc exposures.

What is the NFPA requirement for arc flash? ›

NFPA 70e arc flash requirements

The standards also require that each panel be marked with an Arc Flash Hazard Warning Label. NFPA 70E requires an arc flash risk assessment every five years, for equipment 50 volts or more, for major facility upgrades, and in other cases.

most of you who have the arc flash suit will have one rated 40 cal/cm2 but today you can even get a 100 cal arc flash suit! You'll need to consider the frequency of use and what your highest arc flash levels are but for the most part, companies can purchase one suit and wear it for the above 12cal/cm2 situations.

HRC PPE Category 0: < 1.2 cal/cm2

Clothing – Long sleeve shirt and long pants made of nonmelting or untreated natural fiber (i.e., untreated cotton) with a fabric weight of at least 4.5 oz./square yard.

Arc-flash hazards are also addressed in §1910.335(a)(1)(v), Safeguards for personnel protection, which requires that personal protective Equipment (PPE) for the eyes and face be worn whenever there is danger of injury to the eyes or face from electric arcs or flashes or from flying objects resulting from an electrical ...

most of you who have the arc flash suit will have one rated 40 cal/cm2 but today you can even get a 100 cal arc flash suit! You'll need to consider the frequency of use and what your highest arc flash levels are but for the most part, companies can purchase one suit and wear it for the above 12cal/cm2 situations.

Once again Cal/cm² is for equipment and incident energy. ATPV and EBT are values given to fabric. The Cal/cm² number is displayed on the equipment and the ATPV or EBT value is displayed on the garment label. The garment must have an ATPV or EBT value that is at least equal to or greater than the Cal/cm² number.

Understanding HRC 4 (Hazard Risk Category 4)

This category is reserved for extreme arc flash hazards. We recommend: Arc & Flame Resistant Clothing, Arc Rated Gloves, Arc Face Shield, Arc Hood, Safety Glasses, Arc Balaclava, FR Base Layers.