5/1 NFPA70E Final: NFPA 70E - ELECTRICAL SAFETY TRAINING Exam_2023.
5/1 NFPA70E Final: NFPA 70E - ELECTRICAL SAFETY TRAINING Exam_2023. NFPA 70E, Standard for Electrical Safety in the Workplace, consists of ? chapters; 17 informative annexes; the Foreword to NFPA 70E; and Article 90, Introduction. Chapter 1 is divided into ? articles. The appointment of the NFPA 70E Committee was announced on January 7, ? , and was formed to assist ? in preparing electrical safety standards that would serve its requirements. The 1995 edition of NFPA 70E included the concepts of ? and the establishment of an arc. The 2000 edition continued to focus on establishment of flash protection boundaries, the use of personal protective equipment, and ? to assist the user in applying appropriate protective clothing and personal protective equipment for common tasks. The 2004 edition of NFPA 70E introduced the requirements of ? . The 2018 edition ? all previous editions. NFPA 70E Chapter 1 applies generally to electrical safety in the workplace. Chapter 2 addresses safety-related ? requirements. Chapter 3 ? Chapter 1 with safety requirements for special equipment. Explanatory material is included in the form of informational notes, which are not enforceable as requirements. Brackets containing section references to another NFPA document are for informational purposes only and are provided as a guide to indicate the source of the extracted text. An arc flash hazard is defined in Article 100 as a source of possible injury or damage to health associated with the release of energy caused by an electric arc. Informational Note No. 1 indicates that the likelihood of occurrence of an arc flash incident increases when energized electrical conductors or circuit parts are exposed or when they are within equipment in a(n) ? condition, provided a person is interacting with the equipment in such a manner that could cause an electric arc. An arc flash incident is not likely to occur under normal operating conditions when enclosed energized equipment has been properly installed and ? Arc rating is defined in Article 100, in part, as the value attributed to materials that describes their performance with exposure to an electrical arc discharge and is expressed ? . Informational Note No. 1 states, in part, that arc-rated clothing or equipment has been tested for exposure to an electric arc and that flame-resistant (FR) clothing without an arc rating ? been tested for exposure to an electric arc ATPV is defined in ASTM F1959/F1959M as the incident energy (cal/cm2) on a material or a multilayer system of materials that results in a ? probability that sufficient heat transfer through the tested specimen is predicted to cause the onset of a second degree skin burn injury based on the Stoll curve. EBT is defined in ASTM F 1959-06 as the incident energy (cal/cm2) on a material or a material system that results in a ? probability of break open. The Informational Note to the definition of arc flash boundary states that, according to the Stoll skin burn injury model, the onset of a second degree burn on unprotected skin is likely to occur at an exposure of ? for one second. An approach limit at a distance from an exposed energized electrical conductor or circuit part within which a shock hazard exists An approach limit at a distance from an exposed energized electrical conductor or circuit part within which there is an increased likelihood of electric shock, due to electrical arc-over combined with inadvertent movement When an arc flash hazard exists, an approach limit from an arc source at which incident energy equals 1.2 cal/cm2 (5 J/cm2) An electrical hazard is defined as a dangerous condition such that contact or ? can result in electric shock, arc flash burn, thermal burn, or ? . Incident energy is defined as the amount of thermal energy impressed on a surface, a certain distance from the source, generated during an electrical arc event. Incident energy is typically expressed in ? A qualified person is defined as one who has demonstrated skills and knowledge related to the construction and ? of electrical equipment and installations, and has received safety training to ? the hazards and reduce the associated risk. An unqualified person is defined as a person who is not a qualified person The requirements that address host and contract employer's responsibilities require a number of things. Which of the following are among those requirements? The electrical safety training requirements in 110.2(A) state that employees are required to be trained in a number of topics. Which of the following are among those employee training topics? Determine which of the following are required to meet the NFPA 70E requirements related to emergency response training. The employer must document that each employee has received the training required by 110.2(A). This documentation of training must satisfy which of the following criteria? Identify which of the following statement(s) is/are true as they relate to unqualified persons. Determine which of the following among the NFPA 70E requirements relate to qualified person training, both generally and when such persons are permitted to work within the limited approach boundary. The employer must implement and document an electrical safety program appropriate to the risk associated with electrical hazards. The electrical safety program must identify the ? upon which it is based, the ? by which it is measured and monitored, and the ? to be utilized before work is started by employees exposed to an electrical hazard An electrical safety program in compliance with NFPA 70E must include a risk assessment procedure that addresses the potential for human error and its negative consequences on people, processes, the work environment, and equipment. The job safety planning and job briefing requirements mandate that before starting each job that involves exposure to electrical hazards, the ? must complete a job safety plan and conduct a job briefing with the employees involved. Test instruments, equipment, and their accessories are required to be rated for circuits and equipment to which they will be connected. UL 61010-1, 1, Safety Requirements for Electrical Equipment for Measurement, Control, and Laboratory Use - Part 1: General Requirements, addresses rating and design requirements for voltage measurement and test instruments intended for use on electrical systems ? and below. Only qualified persons are permitted to perform tasks such as testing, troubleshooting, and voltage measuring on electrical equipment operating at voltages equal to or greater than ? . NFPA 70E Chapter 2 addresses Safety-Related ? Requirements, and Chapter 3 addresses Safety Requirements for ? Equipment. NFPA 70E Article 205 addresses General ? Requirements. NFPA 70E Informative Annex H is titled Requirements for the Selection of Protective Clothing and Other Personal Protective Equipment NFPA 70E Informative Annex M is titled ? Protective Clothing and Total System Arc Rating. NFPA 70E Article 250 addresses ? and Protective Equipment. NFPA 70E Article 245 addresses ? Electric Tools and Equipment Portable electric equipment used in highly conductive work locations shall be approved for those locations. In job locations where employees are likely to contact or be drenched with water or conductive liquids, ? shall also be used. GFCI protection devices shall be tested ? . Article 130, Work Involving Electrical Hazards, by definition, covers work involving four hazards caused by either proximity or equipment failure. Article 130 begins with the general requirement stating, in part, that all requirements of Article 130 apply if a(n) ? analysis is completed or if Table 130.7(C)(15)(a), Table 130.7(C)(15)(b), and Table 130.7(C)(15)(c) are used in lieu of an incident energy analysis. ? is a component of an arc flash risk assessment used to predict the incident energy of an arc flash for a specified set of conditions. One of the conditions where energized electrical conductors and circuit parts operating at voltages equal to or greater than 50 volts shall be put into an electrically safe work condition before an employee performs work is where the employee is within the ? boundary Energized work is generally prohibited. Such work is permitted under which of the following conditions? An energized electrical work permit is generally required and documented when working within the limited approach boundary or the arc flash boundary of exposed energized electrical conductors or circuit parts that are not placed in an electrically safe work condition Which of the following are required to be included on an energized electrical work permit? Which of the following are required to be included on an energized electrical work permit? Which of the following are required to be included on an energized electrical work permit? Only ? persons shall be permitted to work on electrical conductors or circuit parts that have not been put into an electrically safe work condition. Appropriate safety-related work practices shall be determined before any person is exposed to the electrical hazards involved by using both shock risk assessment and arc flash risk assessment. A shock risk assessment is required to be performed for which of the following reasons? A qualified person is never permitted to cross the restricted approach boundary. The distance associated with each shock protection approach boundary to exposed energized electrical conductors or circuit parts is determined by the nominal phase-to-phase system voltage range for ? systems and the nominal potential difference for ? voltage systems. (Correct ANS) - AC / DC The term exposed movable conductor is normally applied to overhead line conductors supported by poles. The limited approach boundary distance for an overhead line conductor operating at 480 volts, nominal, is ? . The shock protection approach boundary distances are the distances from exposed energized The limited approach boundary distance for a task involving a fixed circuit part operating at 480 volts, nominal, is ? . An unqualified person is never permitted to cross the restricted approach boundary. The arc flash boundary shall be the distance at which the incident energy equals ? . Which of the following is/are the recognized methods for the selection of protective clothing and other PPE where work will be performed within the arc flash boundary? Which of the following are considerations related to the incident energy analysis method? Electrical equipment such as switchboards, panelboards, industrial control panels, meter socket enclosures, and motor control centers that are in other than dwelling units, and that are likely to require examination, adjustment, servicing, or maintenance while energized, must generally be field marked with a label. Which of the following information must be contained on the label where a label is required? Which of the following are identified as categories of requirements related to precautions for personnel activities? Working within the limited approach boundary at voltages equal to or greater than 50 volts is generally prohibited while alertness is recognizably impaired. When an employee works in a confined or enclosed space that contains exposed energized electrical conductors or circuit parts operating at voltages equal to or greater than 50 volts or where an electrical hazard exists, protective shields, protective barriers, or insulating materials must be ? as necessary to avoid inadvertent contact with these parts and the effects of the electrical hazards Personal protective equipment (PPE), such as arc flash protective equipment, shock protection, and head, face, eye, and hearing protection, is covered in 130.7(C). ? protective equipment, such as insulated tools, protective shields, and rubber insulating equipment used for protection from unintentional contact, is covered in ? . The informational note to 130.7(A) informs that, even when protection is selected in accordance with the PPE requirements of 130.7, some situations could result in burns to the skin, although burn injury should be ? . Which of the following are required by the 130.7(B) provisions addressing the care of protective equipment? The requirements of ? shall apply when the arc flash PPE category method is used for the selection of arc flash PPE. ? parts of the body inside the arc flash boundary shall be protected. When arc-rated clothing is worn to protect an employee, it shall cover all ? clothing. Garments worn as outer layers over arc-rated clothing, such as jackets or rainwear, shall also be made from arc-rated material. Several factors must be considered in the selection of protective clothing. Coverage is one of these factors, and includes which of the following? In addition to meeting other requirements, such as those in 130.7(C)(3) and 130.7(C)(14), head protection must also meet which of the following arc flash protective head protection requirements? In addition to meeting other requirements, such as those in 130.7(C)(7) and 130.7(C)(14), which of the following are accurate statements related to the requirements for hand protection used as arc flash protective equipment? Several requirements cover the care and maintenance of arc-rated clothing and arc flash suits. Identify which of the following statements are true as they relate to these requirements. (Correct ANS) - I. Apparel must be inspected before each use. II. ASTM F 1506 is an example of a standard that contains information on PPE, but it is not a standard that is required to be followed. III. Garments cannot be used where contaminated or damaged to the extent that their protective qualities are impaired. IV. Guidance is provided in ASTM F 1506 when trim, name tags, or logos are affixed to arc-rated garments. V. Manufacturer's instructions for care, maintenance, and cleaning must be followed. VI. The same arc-rated materials used to manufacture the clothing must be used for repair. NFPA 70E requires protective equipment as necessary. It also requires that much of this protective equipment conform to applicable state, federal, or local codes and standards. Identify which of the following statements are true as they relate to standards that protective equipment must meet. In accordance with the requirements in 130.7(C)(15)(a), Table 130.7(C)(15)(a) is to be used to determine which of the following for AC equipment? The arc flash PPE category can be determined through an incident energy analysis. Which of the following statements are true for tasks performed on energized equipment in panelboards or other equipment rated greater than 240 volts and up to 600 volts within the parameters of Table 130.7(C)(15)(a) when arc flash PPE is required? Determination of an arc flash PPE category for a task performed on DC systems is determined from Table 130.7(C)(15)(a). Table ? is used to determine protective clothing and PPE to be used when working within the arc flash boundary based on the determined arc flash PPE category. Arc-rated clothing with a minimum arc rating of ? is required for arc flash PPE Category 2. The following items would meet the protective clothing and personal protective equipment (PPE) requirements for arc flash PPE Category 2, where there is not a need for an arc-rated jacket, parka, rainwear, or hard hat liner: Arc-rated long-sleeve shirt and pants with a minimum arc rating of 8 cal/cm2 Arc-rated faceshield with a minimum arc rating of 8 cal/cm2 Hard hat Safety glasses Hearing protection (ear canal inserts) Heavy duty leather gloves Leather footwear Alerting techniques are located in 130.7 and are therefore a form of protective equipment. Which of the following is/are categories of requirements of alerting techniques? Section 130.8 deals with the requirements for work within the limited approach boundary or arc flash boundary of overhead lines. Which of the following are categories of requirements related to this work? Table 130.7(C)(15)(a) is used to determine whether arc flash PPE is required. For the purposes of using the arc flash PPE category method to select PPE, different types of OCPDs, such as MCCB, ICCBs, and LVPCBs, are all considered to have the same 1.5 cycle typical fault clearing time in the Informational Note to Table 130.7(C)(15)(a). There are five different common overcurrent protection trip types that a circuit breaker may incorporate. Which type is intended for overcurrents that can persist for many seconds to minutes without damaging the conductors or electrical equipment and is considered overload and low-level fault protection? There are five different common overcurrent protection trip types that a circuit breaker may incorporate. Which type is intended for all types of fault current conditions? In this case, the circuit breaker opens as fast as it can, and the exact speed depends on the design. This trip current pickup setting can be fixed or adjustable. There are five different common overcurrent protection trip types that a circuit breaker may incorporate. Which type is a newer feature intended to reduce the incident energy exposure if an arcing fault incident occurs while a worker is working on exposed energized conductors? Some are fixed with no adjustment in time-current characteristics, and others have adjustable current pickup settings. Under fault conditions, current-limiting fuses have the ability to limit the current let-through to less than the available fault current and clear the fault current in 1/2 cycle or less. The combination of decreased clearing times and reduced arcing current can greatly reduce the incident energy when the arcing current is within the current-limiting range. NFPA 70E informational Note to Table 130.7(C)(15)(a) has the typical fault clearing time for molded case circuit breakers as 3-cycle with an instantaneous integral trip NFPA 70E informational Note to Table 130.7(C)(15)(a) has the typical fault clearing time for current-limiting fuses as ? . Energy-reducing maintenance switching (ERMS) is an option to include on larger ampere rated circuit breakers and fused switches with the objective of ? the arcing fault time duration for some range of arcing fault currents. When the energy-reducing maintenance switching (ERMS) option is switched "on" or enabled, the loads on the circuit that the ERMS protects are in energy efficiency mode and energy savings occur. Energy-reducing maintenance switching options can be included with many new circuit breakers and are available to be retrofitted to many existing installed circuit breakers. The overcurrent protective devices utilized in panelboards are either LVPCBs or fuses/switches. The arc flash PPE category method can be used to determine the AFB and the selection of arc flash PPE, if specific conditions and parameters are met. In general terms, which is not a parameter that must be satisfied to use the arc flash PPE category method? ( When using the arc flash PPE category method (for AC systems), the estimated available fault current at the equipment to be worked on must be equal to or less than the available fault current parameter value for the type of equipment in Table 130.7(C)(15)(a). When using the arc flash PPE category method (for AC systems), the fault clearing time has to be greater than the fault clearing time parameter value for the type of equipment to be worked on in Table 130.7(C)(15)(a). When using the arc flash PPE category method, the worker must maintain a working distance less than the working distance parameter value for the type of equipment to be worked on in Table 130.7(C)(15)(a). What are the two methods stated in NFPA 70E 130.5 for determining the proper arc flash PPE? The most common incident energy analysis methods, including equations, are located in NFPA 70E nonmandatory Informative Annex D Which is not one of the three IEEE 1584 methods to calculate incident energy and AFB? What Annex in NFPA 70E provides information on various calculation methods to determine the AFB and incident energy? When using IEEE 1584 Guide for Performing Arc Flash Hazard Calculations for the incident energy analysis method, available fault currents should be calculated for all the various scenarios, such as different switch scenarios and motors running and not running scenarios. The arc flash hazard created during an arc flash event is ? dependent on the OCPD that is protecting the downstream equipment, or the "protecting-OCPD." When conducting an arc flash risk assessment in accordance with 130.5, the "condition of maintenance" is not a consideration. Informational Note No. 2 located after Table 130.5(C) provides the rationale that improper or inadequate maintenance may result in the protecting-OCPD taking longer to clear the fault current than its specified published clearing time. Where equipment is not properly installed or maintained, PPE selection based on incident energy analysis or the PPE category method might not provide adequate protection from arc flash hazards. Maintenance of all electrical equipment that may be worked on when not in an electrically safe work condition is important for electrical safety. According to OSHA 29 Code of Federal Regulations (CFR) 1910.334(b)(2) and NFPA 70E 225.3, which statement below is incorrect when a circuit has been deenergized by a circuit protective device operation due to an overcurrent condition? After a circuit breaker interrupts a fault, it might not be suitable for further service. Maintenance in NFPA 70E is intended for preserving or restoring the condition of electrical power systems equipment or devices for ? . Electrical safety is directly tied to the ? of electrical power systems equipment. The scope of the 2018 NFPA 70E includes: A poorly or improperly maintained OCPD can result in higher actual incident energy during an arc flash incident than determined by an incident energy analysis. NFPA 70E mandates that the employer's electrical safety program include consideration for condition of maintenance of electrical equipment and systems. NFPA 70E 225.3 requires a circuit breaker that has interrupted a fault approaching its interrupting rating to be ? in accordance with the manufacturer's instructions. What is the general subject matter of NFPA 70E, Chapter 2? According to NFPA 70E 210.5, it is not necessary to maintain protective devices to ensure that they can adequately withstand and interrupt available fault current NFPA 70E 205.4 requires overcurrent protective devices to be maintained in accordance with the manufacturers' instructions or industry consensus standards. In addition, 205.4 requires maintenance, tests, and inspections to be ? . If the incident energy for an actual arc-flash event is higher than the incident energy calculated as part of the arc-flash risk assessment, the Electrical Worker may not be wearing sufficient PPE. In addition, workers who thought they were outside the arc-flash boundary may be wearing flammable garments which may be now subject to clothing ignition and other unanticipated consequences. In the IEEE paper "Prioritize Circuit Breaker and Protective Relay Maintenance Using an Arc Flash Hazard Assessment," the study determined that if the closest upstream circuit breaker or relay did not operate and the next higher level upstream OCPD cleared the arcing fault current, in approximately ? of the cases, the worker would not have adequate arc rated PPE. An Electrical Worker can use the data on a(n) ? electrical equipment and the corresponding service report to determine if the equipment has been tested and inspected within a recommended Condition of maintenance is an important electrical safety consideration only for overcurrent protective devices. If a circuit breaker or switch has not been operated in its normal service, a periodic open-close exercise should be planned. When electrical equipment is subject to a clean and dry environment, cleaning is required more frequently than if the environment is humid with a significant amount of dust and other foreign matter Facility operating and local conditions can vary to such an extent that the actual maintenance schedule should be tailored to the environment where the equipment is located. ? provides some frequency of maintenance guidelines as well as guidelines for setting up an electrical preventive maintenance (EPM) program, including sample forms and requirements for electrical system maintenance. If an Electrical Worker is working on energized equipment when justified and wearing arc flash PPE per NFPA 70E 130.5 incident energy analysis, and if the overcurrent protective device fails to operate as designed, or does not operate, the incident energy that the Electrical Worker will be exposed to may be much higher than calculated. ? is "the state of the electrical equipment considering the manufacturers' instructions, manufacturers' recommendations, and applicable industry codes, standards, and recommended practices." The principle in ? is to eliminate or minimize electrical hazards before a worker ever has a chance to become exposed to them. Once an electrical system has been installed and is considered to be an existing system, no safety-related design concepts can be implemented to eliminate or mitigate electrical hazards NFPA 70E Annex F Risk Assessment and Risk Control Sections F.3 and F.4 provide insight to how design concepts and system upgrades can reduce or eliminate electrical hazards. Table F.3, The Hierarchy of Risk Control Methods, lists six Risk Control Methods; the lower the number in this table, the greater the effectiveness in reducing the risk. The design concepts and upgrades discussed pertain to (1) elimination, (2) substitution, and (3) engineering controls in the hierarchy of Table F.3. Safety by design is considered to have less effectiveness than item (6) PPE in the Hierarchy of Risk Control Methods. NFPA 70E Informative Annex O, Safety Related Design Requirements, does not include which of the following concepts? The ? and the ? the current flows are ? related to the energy released by an arcing fault. Overcurrent protective device selection decisions for new systems and for existing system upgrades never affect arc-flash hazards, either positively or negatively. When the fault current is in the current-limiting range of a current-limiting OCPD, the fault current's magnitude and time duration are both increased, which increases the energy released by an arcing fault. When the energy-reducing maintenance switch (ERMS) of a circuit breaker is switched "on," if an arcing fault event occurs on a circuit protected by the circuit breaker, and the arcing fault current is ? the ERMS current pickup, the circuit breaker trips without intentional delay. Which statement is incorrect? Select one: a. After installation, there is no need to be concerned with an OCPD until the device opens. b. Circuit breakers are mechanical OCPDs that require periodic exercise, inspection, testing, and possible maintenance or replacement. c. Modern current-limiting fuses do not require maintenance other than visual examination and ensuring that there is no damage from external thermal conditions (such as conductor terminations), liquids, or physical abuse. d. The reliability of OCPDs in retaining consistent fault-clearing performance over the system life cycle directly impacts arc-flash hazards. Arc-flash relays can be utilized to sound an alarm when an arcing fault occurs so the worker who is working on the energized equipment can gather his or her tools and get out of the arc flash boundary before being injured. In many cases, the incident energy exposures at equipment of existing fusible systems can be reduced by ? . Finger-safe products may reduce the likelihood of an electrical shock hazard. Some component products with finger-safe IP20 claims have a "conditional" IP20 rating. For example, some conductor terminations may be considered IP20 rated if a conductor of a specific AWG is prepared and installed in the terminal properly. Whenever system changes occur in a premise or changes are made by the utility that might increase the available fault currents, the existing OCPDs must be reevaluated to determine whether they have a sufficient interrupting rating. The only purpose of specifying remote monitoring of voltage, current, or measurement of other vital electrical parameters for an electrical control panel or electrical panel is so that the facilities manager or machine operators can see if the equipment is still running properly. It does not provide any safe work practice benefit for the maintenance worker who must troubleshoot equipment while operating. The physical location of a motor disconnecting means has a bearing on the implementation of lockout/tagout. What is not a suitable location for a within-sight motor disconnecting means per NEC 430.102? When racking a circuit breaker, an extended-length racking tool or a remote operated motorized racking tool can be used to move the worker farther from the potential arcing fault source or outside the arc-flash boundary, providing ? . When adding a circuit breaker to a panel or replacing a circuit breaker, it is imperative to ensure that the circuit breaker is suitable for that panel and the circuit breaker has the proper ? and equivalent short-circuit performance. When testing fuses, whether by resistance measurement or voltage measurement, the test probes should contact the metal end caps of ferrule fuses and the blades on knife-blade fuses. ( NFPA 70E 225.3 requires a circuit breaker that has interrupted a fault approaching its interrupting rating to be ? in accordance with the manufacturer's instructions.
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Minneapolis Electrical Jatc
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- nfpa 70e
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nfpa 70e electrical safety training exam
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nfpa 70e electrical safety training
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51 nfpa70e final
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standard for electrical safety in the workplace
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consists of chapters 17 informative ann
