Mighty Fine
In 70E, the small print can be just as important as the big print.
NFPA Journal®, January/February 2009
Don’t overlook the fine print notes when using NFPA 70E® — they contain important information.
Section 90.5(C) of NFPA 70E, Electrical Safety in the Workplace®, defines fine print notes (FPNs) as explanatory material that is informational in nature. They are not a part of the requirements, but they do alert users to the technical committee’s concerns and provide additional information that helps users apply the standard. They should also be considered when developing a site safety program and doing the hazard/risk analysis for work tasks.
Earlier editions of NFPA 70E defined the arc flash protection boundary as the distance from exposed live parts. In the 2009 edition, that definition was changed to the distance from a prospective arc source. Three new FPNs follow the definition of arc flash hazard. The first was added to suggest that normally operating equipment was not a prospective arc source but that it becomes one when equipment changes state, even if the equipment doors are closed.
Distinguishing between equipment with ventilation louvers and equipment without is important. Equipment with louvers will not contain an arc flash, and the gases, smoke, and other products of combustion will escape through the louvers. For that reason, wearing the same personal protective equipment (PPE) in a closed-door situation that you would wear in an open-door situation is important. For equipment without louvers, the hazard/risk analysis should determine what level of PPE to wear. The FPN suggests that some PPE may be necessary, but it does not quantify the level.
The second new FPN clarifies that operating equipment, even with no exposed live parts, is a potential arc flash source. The third FPN refers readers to the standard section for arc flash hazard analysis.
The requirements of Section 110.6(E), Training Documentation, are new, and the section’s FPN proposes that the training record can be part of the overall corporate employment record system, implying that a new record-keeping system is not required.
FPN 2 in Section 110.7(A), Electrical Safety Program—General, identifies ANSI/AIHA Z10 2005, American National Standard for Occupational Safety and Health Management Systems, as a framework for an electrical safety program. Before this addition, employers were required to implement a safety program, but given no guidance as to what it could look like.
FPN 1 in Section 110.7(F), Hazard/Risk Evaluation Procedure, states that the hazard/risk evaluation should consider situations in which a second person is required. Initially, the FPN was a proposal stating that a second person should be required when entering a prohibited approach boundary and that a person trained in CPR should be available within four minutes. The proposal became an FPN because the committee felt that a second person might not always be required, but could be required depending on a risk and task evaluation.
The lockout/tagout procedures of Section 120.2 require that a lock be used. The only exception is in Chapter 120.2(F)(2)(k)(4), which requires an additional safety measure be implemented when using tagout only. The FPN was added to explain what those additional safety measures could be.
FPN 3 of Section 130.1(A), Justification for Work, describes how an arc reacts in enclosed equipment and lists some of the designs available to reduce the system’s arc flash hazard. This is important information for engineers designing systems.
From these new FPNs, readers get significantly more knowledge when they consider not only the requirements, but the additional information they provide. In addition to the standard’s requirements, these FPNs contain subjects to consider when developing a facility or corporate safety program and analyzing hazards and risks for individual tasks.
I encourage you to look at the other FPNs in this edition. Considering the litigious society we live in, it is important not to overlook them.
Bill Buss is senior electrical engineer for NFPA and is staff liason for NFPA 70E.