Prior to 2015, the National Fire Protection Association (NFPA) identified the level of arc flash protection clothing workers must wear by 4 FR Hazardous Risk Categories (HRC). Each of the HRC levels: HRC 1, HRC 2, HRC 3 & HRC 4, corresponded to a minimum arc rating or the level of incident energy measured in calories per centimeter squared. Employers and employees could assess their job task to determine the energy level and arc rating and then use the pre-2015 FR HRC Chart to identify the HRC garment level to wear for their specific job task and the number of garment layers. HRC 1 was the lowest level with a minimum Arc Rating of 4 Cal/cm2 and increased through HRC 2 and HRC 3 up to the highest level, HRC 4 with a minimum Arc Rating of 40 meaning employees falling into this level had the highest exposure to an explosion or arc flash and must therefore where Fire Resistant Garments with the highest level of arc flash protection. In summary, the analysis of shock and arc flash was how risk was quantified.
NFPA 70E HRC Chart: Pre 2015 Changes
NFPA 70E 2015 PPE Categories
As we have become more and more reliant on and heavy users of energy in recent years, Arc Flash accidents in Industrial America have increased and are a tragic reality that claims many lives. There are approx. 10,000 accidents and in excess of 400 deaths each year from arc flash burn injuries such as electrical shock, arc flash and electrocution and the costs to businesses are significant from insurance and legal costs to damaged equipment. As a result of research and technical expertise, the 2015 edition of the NFPA 70E Standard for Electrical Safety in the Workplace introduced revised requirements for workplace electrical hazards.
There were several significant changes in the 2015 NFPA 70E edition. Most notable is the change in how risk should be assessed and the selection of PPE and PPE categories. The changes included revised program requirements around an arc flash risk assessment which entails the identification of the hazard in the NFPA 70E Task Table and then estimating the likelihood of injury severity. The condition of the equipment and type of task now determine whether PPE is required or not. [NFPA 70E 2015, Tables 130.7(C)(15)(A)(b) and 130.7(C)(15)(B)]. The “Hazard Risk Categories” (HRC) were renamed “Arc Flash PPE Categories”.[NFPA 70E 2015Table 130.7(C)(16)] Personal Protective Equipment (PPE) Referencing the table below, you can see the standard renames the old HRC 1 as a the new PPE CAT 1
NFPA 70E 2015 Personal Protective Equipment (PPE) Chart (Table 130.7(C)(16) Personal Protective Equipment (PPE))
Additional Notes from the NFPA 70E 2015 edition include the following:
- There is no Arc Flash PPE Category 0.
- Shirts shall be tucked into pants
- Shirts and Coveralls should be secured at the wrist and closed at the neck.
- Arc Rated Balaclava or Hood is now required where incident energy exposure is greater than 1.2 cal/cm2.
- Arc Rated Full Hood is required where incident energy exposure is greater than 12 cal/cm2.
- Non AR garments worn under AR clothing must be made of all natural, non-melting fibers.
Sources: NFPA 70E Standard for Electrical Safety in the Workplace 2015 Edition
How do I know what PPE Level I need for my job? First and foremost, all employers are required by the US Occupational Safety & Health Administration (OSHA) to supply PPE and all employees are required to wear the PPE. PPE consists of a long list of garments and equipment including arc rated clothing such as pants, shirts, coveralls, jackets, as well as, safety glasses, hard hats, hearing protective devices, gloves and boots. Overall, the greater the electrical hazard, then the higher PPE arc rating an employee must wear.
The National Fire Protection Association (NFPA) represents a group of aligned industry experts whose goal is to ensure their fellow colleagues are safe when working around electrically charged equipment and circuits and one key way to ensure there is knowledge in the industry and safety practices put in place is through research, testing and agreed upon national safety standards. The Federal Occupational Health & Safety Administration (OSHA) leverage NFPA’s knowledge, testing and standards to enact national regulations within the industry with the ultimate goal of minimizing risk and ensuring the US worker can work in a safe environment. If you want to learn more about NFPA and OSHA requirements, visit their websites at www.nfpa.org or www.osha.gov.