- By Roger Ford, Safety and Training Coordinator
The Occupational Safety and Health Administration (OSHA) mandates that companies provide an electrically safe workplace for all personnel. To define what this means, OSHA turns to the National Fire Protection Association (NFPA) and its NFPA 70E standard.
NFPA 70E continues to evolve as new thinking on electrical safety is introduced. The latest edition, NFPA 70E 2012, has changed significantly from the 2009 edition of the standard, and to help you understand how 70E 2012 impacts your company, D.L. Steiner has prepared this summary of its most notable updates.
Audits—NFPA 70E 2012 requires that companies now conduct regular audits of their entire electrical safety program at specified time intervals.
Worker performance must now be audited at least annually to verify that qualified workers are complying with 70E standards (Article 110.2[D][f]).
Formal audits of the company electrical safety program must now be completed on a frequency not to exceed three years (Article 110.3[H]). This includes fieldwork to verify that the safety program is being followed. If it isn’t, training must be changed.
Electrical safety audits and their results must now be documented.
Electrical Safety Training—NFPA 70E 2012 contains two important new mandates related to safety training:
- A facility’s electrical workers must now undergo retraining in electrical safety at a minimum of every three years (Article 110.2[D)][d]).
- The documentation for electrical safety courses must now contain course content, as well as the date of the training and the names of the people who were trained (Article 110.2[E]).
Safety Practices—NFPA 70E includes procedures for managing risks associated with working near electrical energy. Some of these have changed noticeably for 70E 2012.
Previously, NFPA 70E required the electrically safe work condition (exposed conductors disconnected from power source, locked and tagged, tested for zero voltage, grounded, if necessary) whenever a worker worked within the limited approach boundary for exposed energized conductors. For 70E 2012, the electrically safe work condition is required, even if energized conductors aren’t exposed but the worker interacts with equipment in a way that increases the risk of injury due to an arc flash (Article 130.2).
Earlier NFPA 70E editions required an energized electrical work permit whenever a worker worked inside the limited approach boundary of live electrical equipment that couldn’t be placed in the electrically safe work condition. 70E 2012 requires the permit for work performed within the arc flash boundary of exposed energized electrical conductors (Article 130.2[B] ; Informative Annex J).
The 2009 edition of 70E contained a lockout/tagout procedure that permitted electrical workers to de-energize a circuit without applying locks or tags (Article 120.2[D], 2009 edition). This procedure conflicted with OSHA electrical safety standards and has been removed from 70E 2012.
Arc Flash Hazard—In previous 70E editions, arc flash hazard analysis included establishing the arc flash protection boundary and selecting the PPE (personal protective equipment) required to work safely in the presence of the arc flash hazard. Under 70E 2012, arc flash hazard analysis includes establishing the incident energy level at the working distance, plus establishing the arc flash boundary and selecting PPE (Article 130.5).
The default 4′ arc flash protection boundary of earlier 70E editions has been removed from 70E 2012. This boundary is now specified in inches for each unique situation and comes from one of two task tables: Table 130.7(C)(15)(a) for AC and Table 130.7(C)(15)(b) for DC. These tables also list the fault current, clearing time, and working distance of protective devices in the heading of each table section. This eliminates searching table endnotes to verify that a task fits within established limits.
Under 70E 2012, electrical systems of 240 Volts or less with a transformer rated 125 kVA or less are no longer exempt from the arc flash hazard analysis mandate (Article 130.5). For guidance assessing the arc flash hazard of these systems, see IEEE 1584.
Labeling—Previously, electrical equipment safety labels could include the information of either incident energy or required PPE level. NFPA 70E 2012 mandates that these labels contain more extensive safety information (Article 130.5[C])—
- At least one of the following: (1) available incident energy;(2) minimum arc rating of clothing; (3) required PPE level; (4) highest HRC (hazard risk category) for the equipment
- Date of arc flash hazard analysis
- Nominal system voltage
- Arc flash boundary
PPE—70E 2012 makes significant changes to the way PPE is used:
- The 2* Category has been deleted.
- Incident energy calculation method for selecting PPE—The balaclava (sock hood) must be worn with a face shield if the back of the head is within the arc flash protection boundary (Article 130.7[b]).
- Incident energy calculation method for selecting PPE—An arc flash hood must be used if the anticipated incident energy exposures exceeds 12 calories/cm2 (Article 130.7[b]).
- Table method for selecting PPE— The balaclava and face shield must be worn if the task table indicates Category 2 (Table 130.7[C)]).
New DC Information—NFPA 70E 2012 includes two new tables for assessing electrical hazards while working with DC voltages.
- Table 130.4(C)(b) lists approach boundaries for protection against shock while working with DC electrical conductors or circuit parts.
- Table 130.7(C)(15)(b) lists the arc flash hazard risk category classifications of different tasks performed on DC equipment. Previously, NFPA 70E did not cover DC equipment in any detail.
NPFA 70E 2012 is a major step forward in workplace electrical safety, but it will no doubt raise questions not addressed by the information we’ve provided. For help interpreting this new standard to ensure your company complies with its mandates, please contact D.L. Steiner.