DMV Practice Test Hub › OSHA Elec › Grounding and Bonding

OSHA Elec test topic: grounding and Bonding

135 test-style questions with the answer and the exact rule.

Electrical safety training providers? Feature it at the top of this page — $49 for 30 days →

1. An electrician is installing a disconnecting means for X-ray equipment connected to a 120-volt branch circuit rated at 20 amperes. What component may serve as the disconnecting means?A grounding-type attachment plug cap and receptacle of proper rating. For low-voltage (120V) and low-amperage (30A or less) X-ray circuits, a proper grounding plug and receptacle are permitted to act as the disconnect.
   29 CFR § 1910.306(f): “For equipment connected to a 120-volt branch circuit of 30 amperes or less, a grounding-type attachment plug cap and receptacle of proper rating may serve as a disconnecting means.”
2. When determining 'Voltage to ground' for an ungrounded circuit, what measurement must the electrician take?The greatest voltage between the given conductor and any other conductor of the circuit. For ungrounded circuits, the definition specifies using the greatest voltage between the given conductor and any other conductor in the circuit.
   29 CFR § 1926.449: “Voltage to ground. For grounded circuits, the voltage between the given conductor and that point or conductor of the circuit that is grounded; for ungrounded circuits, the greatest voltage between the given conductor and any other conductor of the circuit.”
3. A foreman is reviewing a 'Separately derived system' for a temporary generator setup. What characteristic distinguishes this system from other premises wiring systems?It has no direct electrical connection to supply conductors originating in another system. The definition specifies that a separately derived system lacks a direct electrical connection to other systems, whereas the other options contradict or are not part of the definition.
   29 CFR § 1926.449: “A premises wiring system whose power is derived from generator, transformer, or converter windings and has no direct electrical connection, including a solidly connected grounded circuit conductor, to supply conductors originating in another system.”
4. An industrial worker is connecting a remote pendant pushbutton control for a crane in a cell line working zone. To prevent hazardous electrical conditions, which characteristic must the supporting means and surfaces of the pendant have?Nonconductive supporting means with nonconductive surfaces or ungrounded exposed conductive surfaces. The regulation requires the pendant to have nonconductive supports and either nonconductive surfaces or exposed conductive surfaces that are not grounded.
   29 CFR § 1910.306(h): “Pendant pushbutton with nonconductive supporting means and with nonconductive surfaces or ungrounded exposed conductive surfaces; or”
5. When identifying conductors or terminals in a wiring system, what does the term 'Identified' specifically mean regarding the conductor's status?It can be recognized as grounded. For conductors and terminals, 'identified' means they can be recognized as grounded, distinguishing them from ungrounded conductors.
   29 CFR § 1926.449: “Identified (conductors or terminals). Identified, as used in reference to a conductor or its terminal, means that such conductor or terminal can be recognized as grounded.”
6. An industrial worker is operating equipment within the electrolytic cell line working zone. According to the definition of 'Cell line attachments and auxiliary equipment', which of the following is considered auxiliary equipment in this zone?Exposed conductive surfaces of ungrounded cranes. The rule lists exposed conductive surfaces of ungrounded cranes as auxiliary equipment within the working zone.
   29 CFR § 1910.399: “In the cell line working zone, auxiliary equipment includes the exposed conductive surfaces of ungrounded cranes and crane-mounted cell-servicing equipment.”
7. A technician is evaluating whether a metal rack supporting electric equipment is considered effectively grounded. What condition must be met for this status?The equipment must be secured to and in electrical contact with the metal rack, which is itself grounded per fixed equipment rules. Effective grounding is achieved when the equipment is in electrical contact with a grounded metal rack or structure that supports it.
   29 CFR § 1926.404(f): “Electric equipment is considered to be effectively grounded if it is secured to, and in electrical contact with, a metal rack or structure that is provided for its support and the metal rack or structure is grounded by the method specified for the noncurrent-carrying metal parts of fixed equipment in paragraph (f)(8)(i) of this section.”
8. An electrician is installing fixed equipment that requires grounding. Which method of grounding the noncurrent-carrying metal parts is compliant with OSHA standards for AC circuits?Using an equipment grounding conductor contained within the same raceway, cable, or cord as the circuit conductors. For AC circuits, the grounding conductor must be contained within the same raceway, cable, or cord as the circuit conductors; running it separately is only permitted for DC circuits.
   29 CFR § 1910.304(g): “Noncurrent-carrying metal parts of fixed equipment, if required to be grounded by this subpart, shall be grounded by an equipment grounding conductor that is contained within the same raceway, cable, or cord, or runs with or encloses the circuit conductors.”
9. An electrician is installing aboveground conductors for a system over 600 volts in an area accessible only to qualified persons. Which of the following conductor types is permitted for open runs in this specific location?Bare conductors. The regulation permits bare conductors for open runs in areas accessible only to qualified persons, whereas braided coverings require specific support to prevent damage and are not the primary 'open run' exception for bare types.
   29 CFR § 1910.308(a): “In locations accessible to qualified persons only, open runs of Type MV cables, bare conductors, and bare busbars are also permitted.”
10. Before reenergizing circuits or equipment, a qualified person must conduct tests and visual inspections to verify that which of the following have been removed so the circuits can be safely energized?All tools, electrical jumpers, shorts, grounds, and other such devices. The regulation lists tools, jumpers, shorts, and grounds as the specific items that must be removed before reenergizing.
    29 CFR § 1910.333(b): “A qualified person shall conduct tests and visual inspections, as necessary, to verify that all tools, electrical jumpers, shorts, grounds, and other such devices have been removed, so that the circuits and equipment can be safely energized.”
11. A worker is preparing to bond a metal raceway to an equipment enclosure to ensure electrical continuity. What must be done to the contact surfaces before making the connection?Remove any nonconductive paint, enamel, or similar coating at threads, contact points, and contact surfaces. To ensure effective bonding and electrical continuity, nonconductive coatings like paint or enamel must be removed from contact points unless specific fittings are used.
    29 CFR § 1910.305(a): “Any nonconductive paint, enamel, or similar coating shall be removed at threads, contact points, and contact surfaces or be connected by means of fittings designed so as to make such removal unnecessary.”
12. When grounding a vehicle-mounted generator system, which of the following is a required condition for the vehicle frame to serve as the grounding electrode?The generator frame must be bonded to the vehicle frame. The regulation requires that the generator frame be bonded to the vehicle frame for the vehicle frame to serve as the grounding electrode.
    29 CFR § 1910.304(g): “The frame of a vehicle need not be grounded and may serve as the grounding electrode for a system supplied by a generator located on the vehicle under the following conditions: (A) The frame of the generator is bonded to the vehicle frame;”
13. An electrician is installing a disconnecting means for an elevator driving machine located in a remote machinery space. What capability must this single disconnecting means possess to comply with safety standards?It must be capable of being locked in the open position. For elevators with driving machines in remote spaces, the code mandates that the disconnecting means can be locked open to ensure safe isolation.
    29 CFR § 1910.306(c): “Where the driving machine is located in a remote machinery space, a single disconnecting means for disconnecting all ungrounded main power supply conductors shall be provided and be capable of being locked in the open position.”
14. An electrician is replacing a nongrounding-type receptacle in an enclosure that lacks a grounding means. If the electrician chooses to install a grounding-type receptacle supplied through a ground-fault circuit-interrupter, what specific markings must the replacement receptacle bear?It must be marked "GFCI Protected" and "No Equipment Ground.". The regulation requires these two specific markings when a grounding-type receptacle is used as a replacement in a non-grounded enclosure supplied by a GFCI.
    29 CFR § 1910.304(b): “A nongrounding-type receptacle may be replaced with a grounding-type receptacle where supplied through a ground-fault circuit-interrupter; the replacement receptacle shall be marked “GFCI Protected” and “No Equipment Ground;””
15. If an electrician uses single-pole separable connectors where interlocking is not possible, what sequence must be followed for connecting and disconnecting the conductors to ensure safety?Connect equipment grounding conductor, then grounded circuit conductor, then ungrounded conductor; disconnect in reverse order. To protect against shock, the ground must be connected first and disconnected last, ensuring the equipment is grounded before becoming energized.
    29 CFR § 1910.306(k): “Line connectors are of the listed sequential-interlocking type so that load connectors are connected in the following sequence: (i) Equipment grounding conductor connection; (ii) Grounded circuit-conductor connection, if provided; and (iii) Ungrounded conductor connection; and so that disconnection is in the reverse order”
16. An electrician is installing metal raceways for conductors in a new construction project. Which of the following is the correct requirement for these metal raceways?They must be grounded. The rule states that metal raceways shall be grounded, and the exceptions provided (such as the 25-foot rule) apply specifically to enclosures added to existing installations, not to new raceway installations.
    29 CFR § 1926.404(f): “Metal cable trays, metal raceways, and metal enclosures for conductors shall be grounded, except that: (A) Metal enclosures such as sleeves that are used to protect cable assemblies from physical damage need not be grounded; and (B) Metal enclosures for conductors added to existing installations of open wire, knob-and-tube wiring, and nonmetallic-sheathed cable need not be grounded if all of the following conditions are met:”
17. An electrician is installing distribution apparatus, such as a transformer case, on a wooden pole. Under which specific condition is grounding of the exposed noncurrent-carrying metal parts NOT required?If the apparatus is mounted at a height exceeding 2.44 m (8.0 ft) above ground or grade level. The rule lists distribution apparatus on wooden poles above 8 feet as an exception to the grounding requirement for fixed equipment.
    29 CFR § 1910.304(g): “Distribution apparatus, such as transformer and capacitor cases, mounted on wooden poles, at a height exceeding 2.44 m (8.0 ft) above ground or grade level”
18. An electrician is connecting a grounded conductor to a terminal. What condition must be avoided to comply with polarity rules?Attaching the conductor so as to reverse designated polarity. The rule strictly prohibits attaching a grounded conductor in a way that reverses the designated polarity of the connection.
    29 CFR § 1910.304(a): “No grounded conductor may be attached to any terminal or lead so as to reverse designated polarity.”
19. When using portable electric equipment within the cell line working zone, under which specific condition are the frames and enclosures permitted to be grounded?If the cell line circuit voltage does not exceed 200 volts DC or the frames are guarded. Grounding of frames is generally prohibited in the working zone unless the voltage is low (≤200 V DC) or the frames are physically guarded.
    29 CFR § 1910.306(h): “The frames and enclosures of portable electric equipment used within the cell line working zone may not be grounded, unless the cell line circuit voltage does not exceed 200 volts DC or the frames are guarded.”
20. An industrial worker is installing a device intended to protect personnel by deenergizing a circuit when current to ground exceeds a predetermined value lower than that required to trip the overcurrent device. What is this device called?Ground-fault circuit-interrupter. The rule defines the ground-fault circuit-interrupter as the specific device designed for personnel protection by deenergizing circuits upon detecting ground faults below the overcurrent device's trip threshold.
    29 CFR § 1910.399: “Ground-fault circuit-interrupter. A device intended for the protection of personnel that functions to deenergize a circuit or a portion of a circuit within an established period of time when a current to ground exceeds some predetermined value that is less than that required to operate the overcurrent protective device of the supply circuit.”
21. An electrician is setting up circuits to supply power to ungrounded receptacles for hand-held, cord- and plug-connected equipment in a cell line working zone. Which requirement must these circuits meet?They must be supplied through isolating transformers with a secondary voltage not exceeding 300 volts between conductors. The rule specifies that isolating transformers used for these circuits must have a secondary voltage not exceeding 300 volts between conductors.
    29 CFR § 1910.306(h): “The secondary voltage of the isolating transformers may not exceed 300 volts between conductors; and (D) All circuits supplied from the secondaries shall be ungrounded and shall have an approved overcurrent device of proper rating in each conductor.”
22. An electrician is installing a new 120/240V single-phase, three-wire service for a commercial building. According to OSHA grounding requirements for systems to be grounded, which conductor must be grounded?The neutral conductor. For single-phase, three-wire systems, the regulation requires the neutral conductor to be the grounded conductor.
    29 CFR § 1910.304(g): “The neutral conductor of a single-phase, three-wire system shall be grounded;”
23. An electrician is wiring a vehicle-mounted generator system. The generator frame is bonded to the vehicle frame, and the generator supplies only equipment located on the vehicle. To use the vehicle frame as the grounding electrode, what must be true regarding the equipment grounding conductor terminals of the receptacles?They are bonded to the generator frame. The regulation specifically requires that receptacle grounding terminals be bonded to the generator frame, not directly to the vehicle frame, even when the generator is vehicle-mounted.
    29 CFR § 1926.404(f): “The noncurrent-carrying metal parts of equipment and the equipment grounding conductor terminals of the receptacles are bonded to the generator frame”
24. An electrician is working on a circuit over 600 volts where a permanent connection to earth is required to ensure that ground fault current cannot build up to dangerous voltages. What is the specific term for this type of connection?Grounded, effectively. The definition for 'Grounded, effectively' specifies that for circuits over 600 volts, the connection must be permanent with low impedance and sufficient ampacity to prevent dangerous voltage buildup from ground faults.
    29 CFR § 1926.449: “Grounded, effectively (Over 600 volts, nominal.) Permanently connected to earth through a ground connection of sufficiently low impedance and having sufficient ampacity that ground fault current which may occur cannot build up to voltages dangerous to personnel.”
25. What is the requirement for the test records of equipment grounding conductors under the assured equipment grounding conductor program?They must identify each receptacle, cord set, and cord- and plug-connected equipment that passed the test and indicate the last date it was tested. The record must specifically identify the equipment that passed and the date of the test, and it must be available on the jobsite for inspection.
    29 CFR § 1926.404(b): “This test record shall identify each receptacle, cord set, and cord- and plug-connected equipment that passed the test and shall indicate the last date it was tested or the interval for which it was tested.”
26. An electrician is selecting a device to protect personnel from shock in a wet environment. Which device functions to deenergize the circuit when a current to ground exceeds a predetermined value less than that required to operate the overcurrent protective device?A ground-fault circuit interrupter. The GFCI is specifically defined as the device that deenergizes the circuit when ground current exceeds a set value lower than the overcurrent device's trip threshold.
    29 CFR § 1926.449: “Ground-fault circuit interrupter. A device for the protection of personnel that functions to deenergize a circuit or portion thereof within an established period of time when a current to ground exceeds some predetermined value that is less than that required to operate the overcurrent protective device of the supply circuit.”
27. What is the requirement for test records under an assured equipment grounding conductor program for temporary wiring?The record must identify each receptacle, cord set, and cord- and plug-connected equipment that passed the test and indicate the last date it was tested. Test records must specifically identify the equipment that passed and provide the date or interval of the last test.
    29 CFR § 1910.304(b): “This test record shall identify each receptacle, cord set, and cord- and plug-connected equipment that passed the test and shall indicate the last date it was tested or the interval for which it was tested.”
28. A worker is installing aboveground conductors for a system over 600 volts in a general industrial area (not restricted to qualified persons). Which of the following is NOT a permitted method for installing these conductors?Open runs of bare busbars. Open runs of bare busbars are only permitted in locations accessible to qualified persons only; in general areas, they must be in raceways, trays, or as metal-clad cable.
    29 CFR § 1910.308(a): “Aboveground conductors shall be installed in rigid metal conduit, in intermediate metal conduit, in electrical metallic tubing, in rigid nonmetallic conduit, in cable trays, as busways, as cablebus, in other identified raceways, or as open runs of metal-clad cable suitable for the use and purpose.”
29. A qualified electrician is selecting a disconnecting means for a photovoltaic power source where the circuit grounding connection is NOT designed to be automatically interrupted by the ground-fault protection system. What configuration is prohibited for the switch or circuit breaker used as the disconnecting means?It must have a pole in the grounded conductor. If the ground-fault protection does not automatically interrupt the grounding connection, the disconnecting device is forbidden from having a pole in the grounded conductor.
    29 CFR § 1910.308(f): “Where a circuit grounding connection is not designed to be automatically interrupted as part of the ground-fault protection system, a switch or circuit breaker used as disconnecting means may not have a pole in the grounded conductor.”
30. A worker is using a temporary 125-volt, single-phase, 30-ampere receptacle outlet for a construction activity. The outlet is not part of the permanent wiring. What is required for this specific receptacle?Ground-fault circuit-interrupter protection for personnel. Temporary 15-, 20-, and 30-ampere single-phase receptacles must have GFCI protection; the assured grounding program is only for receptacles outside this specific voltage/amperage range.
    29 CFR § 1910.304(b): “All 125-volt, single-phase,15-, 20-, and 30-ampere receptacle outlets that are not part of the permanent wiring of the building or structure and that are in use by personnel shall have ground-fault circuit-interrupter protection for personnel.”
31. An electrician is installing temporary wiring for a remodeling project. They are using a 240-volt, three-phase receptacle that is not part of the permanent building wiring. GFCI protection is not available for this specific receptacle type. What must the employer establish and implement to allow employees to use this receptacle?An assured equipment grounding conductor program covering cord sets, receptacles, and equipment connected by cord and plug. When GFCI protection is unavailable for non-standard temporary receptacles, the regulation mandates an assured equipment grounding conductor program.
    29 CFR § 1910.304(b): “Where the ground-fault circuit-interrupter protection required by paragraph (b)(3)(ii)(B) of this section is not available for receptacles other than 125-volt, single-phase, 15-, 20-, and 30-ampere, the employer shall establish and implement an assured equipment grounding conductor program covering cord sets, receptacles that are not a part of the building or structure, and equipment connected by cord and plug that are available for use or used by employees on those receptacles.”
32. A vehicle near energized overhead lines is intentionally grounded. What precaution must ground workers take regarding the grounding location?Ground workers may not stand at the grounding location whenever there is a possibility of overhead line contact. Workers must avoid standing at the grounding point if there is any risk of the vehicle contacting the overhead lines to prevent exposure to hazardous ground potentials.
    29 CFR § 1910.333(c): “employees working on the ground near the point of grounding may not stand at the grounding location whenever there is a possibility of overhead line contact.”
33. A worker is using a 120-volt, single-phase, 20-ampere receptacle outlet on a construction site that is not part of the permanent building wiring. What protection is required for personnel safety?Approved ground-fault circuit interrupters. Temporary 120V, 15- or 20-amp receptacles on construction sites must be protected by approved GFCIs for personnel safety.
    29 CFR § 1926.404(b): “All 120-volt, single-phase, 15- and 20-ampere receptacle outlets on construction sites, which are not a part of the permanent wiring of the building or structure and which are in use by employees, shall have approved ground-fault circuit interrupters for personnel protection.”
34. Regarding the grounding path for circuits, equipment, and enclosures, what characteristic must the path to ground possess according to the standard?Permanent and continuous. The rule mandates that the grounding path must be both permanent and continuous, ruling out temporary or intermittent paths.
    29 CFR § 1926.404(f): “The path to ground from circuits, equipment, and enclosures shall be permanent and continuous.”
35. An industrial worker is evaluating a water feature constructed in the ground that is primarily for aesthetic value, cannot be readily disassembled for storage, and is not intended for swimming. How is this facility classified for electrical safety purposes?Permanently installed decorative fountain. The rule defines permanently installed decorative fountains as units constructed in the ground, not readily disassembled, and primarily for aesthetic value rather than swimming.
    29 CFR § 1910.399: “Permanently installed decorative fountains and reflection pools. Pools that are constructed in the ground, on the ground, or in a building in such a manner that the fountain or pool cannot be readily disassembled for storage, whether or not served by electrical circuits of any nature. These units are primarily constructed for their aesthetic value and are not intended for swimming or wading.”
36. Under an assured equipment grounding conductor program, how often must a cord set that is fixed and not exposed to damage be tested?At intervals not exceeding 6 months. While most cord sets require testing every 3 months, those that are fixed and not exposed to damage have an extended testing interval of 6 months.
    29 CFR § 1926.404(b): “At intervals not to exceed 3 months, except that cord sets and receptacles which are fixed and not exposed to damage shall be tested at intervals not exceeding 6 months.”
37. An unqualified worker is on the ground near energized overhead lines. What restriction applies to the worker regarding conductive objects?The worker may not bring any conductive object closer to unguarded, energized overhead lines than the distances given in paragraph (c)(3)(i)(A). Unqualified persons on the ground are strictly prohibited from bringing conductive objects closer than the specified minimum approach distances.
    29 CFR § 1910.333(c): “When an unqualified person is working on the ground in the vicinity of overhead lines, the person may not bring any conductive object closer to unguarded, energized overhead lines than the distances given in paragraph (c)(3)(i)(A) of this section.”
38. A worker is identifying the type of service-entrance cable used for an underground installation. According to the definition of 'Service-entrance cable,' what characterizes Type USE cable?It is identified for underground use and has a moisture-resistant covering, but is not required to have a flame-retardant covering. The rule specifies that Type USE is for underground use with a moisture-resistant covering but does not require a flame-retardant covering, unlike Type SE.
    29 CFR § 1910.399: “Type USE. Type USE, identified for underground use, having a moisture-resistant covering, but not required to have a flame-retardant covering.”
39. An electrician is installing a multiwire branch circuit for temporary power in a construction site. At which location must the means to disconnect simultaneously all ungrounded conductors be provided?At the power outlet or panelboard where the branch circuit originated. The regulation requires the simultaneous disconnecting means for multiwire branch circuits to be located at the origin point (outlet or panelboard), not at the load or other arbitrary points.
    29 CFR § 1910.305(a): “Multiwire branch circuits shall be provided with a means to disconnect simultaneously all ungrounded conductors at the power outlet or panelboard where the branch circuit originated.”
40. An industrial worker is operating induction heating equipment with a hinged access door. Under which condition is an interlock switch NOT required on this access door?When the applicator is an induction heating coil at dc ground potential. Interlocks are not required if the applicator is an induction heating coil at dc ground potential or operates at less than 150 volts ac; 200 volts ac exceeds the exemption threshold.
    29 CFR § 1910.306(g): “Interlock switches shall be used on all hinged access doors, sliding panels, or other such means of access to the applicator, unless the applicator is an induction heating coil at dc ground potential or operating at less than 150 volts ac.”
41. Under an assured equipment grounding conductor program for temporary wiring, how often must cord sets and receptacles that are fixed and not exposed to damage be tested?At intervals not exceeding 6 months. The regulation specifies a longer testing interval of 6 months for fixed cord sets and receptacles not exposed to damage, compared to the standard 3-month interval.
    29 CFR § 1910.304(b): “All required tests shall be performed before first use; before equipment is returned to service following any repairs; before equipment is used after any incident which can be reasonably suspected to have caused damage (for example, when a cord set is run over); and at intervals not to exceed 3 months, except that cord sets and receptacles which are fixed and not exposed to damage shall be tested at intervals not exceeding 6 months;”
42. A worker uses a cord-and-plug-connected tool in a wet location. The tool is not double-insulated. Under what specific condition is the tool exempt from the requirement to have its exposed noncurrent-carrying metal parts grounded?It is supplied through an isolating transformer with an ungrounded secondary of not over 50 volts. The rule specifies that the exemption requires an isolating transformer (not standard) with an ungrounded secondary (not grounded) limited to 50 volts (not 100 or 150).
    29 CFR § 1926.404(f): “Tools likely to be used in wet and/or conductive locations need not be grounded if supplied through an isolating transformer with an ungrounded secondary of not over 50 volts.”
43. A worker is using a grounding-type device on a receptacle. For what purpose is this device allowed to be used?For grounding only. The regulation restricts the use of grounding terminals to grounding purposes only, prohibiting other uses like neutral returns or mechanical support.
    29 CFR § 1910.304(a): “A grounding terminal or grounding-type device on a receptacle, cord connector, or attachment plug may not be used for purposes other than grounding.”
44. An electrician is working near overhead electric light and power circuits of over 150 volts to ground. What is the primary requirement for the location of outdoor metal structures supporting antennas?They shall be located as far away from the circuits as necessary to avoid the possibility of falling into or making accidental contact. The regulation requires sufficient distance to prevent accidental contact or falling into circuits over 150 volts to ground.
    29 CFR § 1926.408(c): “Outdoor metal structures supporting antennas, as well as self-supporting antennas such as vertical rods or dipole structures, shall be located as far away from overhead conductors of electric light and power circuits of over 150 volts to ground as necessary to avoid the possibility of the antenna or structure falling into or making accidental contact with such circuits.”
45. In a tunnel installation, what is the requirement for the equipment grounding conductor when using a metal raceway or multiconductor cable?It shall be run with circuit conductors inside the metal raceway or inside the multiconductor cable jacket. The rule mandates that the equipment grounding conductor be included within the same raceway or cable jacket as the circuit conductors.
    29 CFR § 1910.308(a): “An equipment grounding conductor shall be run with circuit conductors inside the metal raceway or inside the multiconductor cable jacket. The equipment grounding conductor may be insulated or bare.”
46. A worker is installing wiring in a vehicle-washing area where the location is subject to saturation with water. Based on the location classifications, how should this area be categorized for electrical installation purposes?Wet location. The rule lists vehicle-washing areas as examples of locations subject to saturation with water, which defines them as wet locations.
    29 CFR § 1910.399: “Wet location. Installations underground or in concrete slabs or masonry in direct contact with the earth, and locations subject to saturation with water or other liquids, such as vehicle-washing areas, and locations unprotected and exposed to weather.”
47. An electrician is installing a portable distribution box outdoors for a temporary event. To comply with OSHA requirements regarding exposure to live parts and weather, how must the box be constructed and mounted?It must be of weatherproof construction and mounted so the bottom of the enclosure is not less than 6 inches above the ground. The regulation requires weatherproof construction for outdoor boxes and specifies a minimum mounting height of 6 inches to prevent water ingress and accidental contact.
    29 CFR § 1910.306(k): “Where installed outdoors, the box shall be of weatherproof construction and mounted so that the bottom of the enclosure is not less than 152 mm (6 in.) above the ground”
48. An electrician is working on a motor controller where live parts operating at over 150 volts to ground are guarded against accidental contact only by location. If adjustment or attendance is necessary during operation, what additional safety measure is required?Insulating mats or platforms shall be provided so that the attendant cannot readily touch live parts unless standing on the mats or platforms. The rule specifically requires insulating mats or platforms for attendants working on apparatus over 150 volts to ground when guarded only by location.
    29 CFR § 1926.405(j): “Where live parts of motors or controllers operating at over 150 volts to ground are guarded against accidental contact only by location, and where adjustment or other attendance may be necessary during the operation of the apparatus, insulating mats or platforms shall be provided so that the attendant cannot readily touch live parts unless standing on the mats or platforms.”
49. An electrician is working in an area where the exact location of underground electric powerlines is unknown. They are using a jack-hammer to break up pavement. What specific PPE must the employer provide to protect against contacting a line?Insulated protective gloves. The regulation mandates insulated protective gloves for employees using hand tools like jack-hammers in areas with unknown underground lines.
    29 CFR § 1926.416(a): “In work areas where the exact location of underground electric powerlines is unknown, employees using jack-hammers, bars, or other hand tools which may contact a line shall be provided with insulated protective gloves.”
50. A worker is preparing a made electrode for grounding a temporary construction site. Which condition must the electrode meet before installation?It must be free from nonconductive coatings such as paint or enamel. The rule states that made electrodes must be free from nonconductive coatings like paint or enamel to ensure proper grounding.
    29 CFR § 1926.404(f): “If made electrodes are used, they shall be free from nonconductive coatings, such as paint or enamel; and, if practicable, they shall be embedded below permanent moisture level.”
51. An electrician is grounding the noncurrent-carrying metal parts of fixed equipment. How must the equipment grounding conductor be routed relative to the circuit conductors?It must be contained within the same raceway, cable, or cord, or run with or enclose the circuit conductors. For fixed equipment, the grounding conductor must be physically associated with the circuit conductors (same raceway/cable/cord or running with them), except for DC circuits where it may be separate.
    29 CFR § 1926.404(f): “Noncurrent-carrying metal parts of fixed equipment, if required to be grounded by this subpart, shall be grounded by an equipment grounding conductor which is contained within the same raceway, cable, or cord, or runs with or encloses the circuit conductors.”
52. Who must be designated by the employer to implement the assured equipment grounding conductor program for temporary wiring?One or more competent persons. The rule specifically requires the designation of 'competent persons' to implement the program, not just any employee or external agency official.
    29 CFR § 1910.304(b): “The employer shall designate one or more competent persons to implement the program;”
53. What is the maximum interval for bonding nonenergized metal parts and raceways to metal pipes and rails throughout a tunnel?305 m (1000 ft). The regulation specifies that bonding to pipes and rails must occur at the portal and at intervals not exceeding 305 meters (1000 feet).
    29 CFR § 1910.308(a): “All nonenergized metal parts of electric equipment and metal raceways and cable sheaths shall be effectively grounded and bonded to all metal pipes and rails at the portal and at intervals not exceeding 305 m (1000 ft) throughout the tunnel.”
54. When wiring a separately derived system where the generator is a component, an electrician must bond the neutral conductor to the generator frame. What is the rule regarding other conductors in this specific scenario?No other conductor need be bonded to the generator frame. The rule states that while the neutral must be bonded to the generator frame in a separately derived system, no other conductors require this specific bonding.
    29 CFR § 1926.404(f): “A neutral conductor shall be bonded to the generator frame if the generator is a component of a separately derived system. No other conductor need be bonded to the generator frame.”
55. An electrician is installing power receptacles for ungrounded portable electric equipment within a cell line working zone. To comply with OSHA requirements for these specific receptacles and their mating plugs, which configuration must be used?They must be of a configuration that prevents their use for equipment required to be grounded. The regulation requires that receptacles for ungrounded equipment lack a grounding conductor provision and have a unique configuration to prevent accidental use with grounded equipment.
    29 CFR § 1910.306(h): “Receptacles and their mating plugs for ungrounded equipment may not have provision for a grounding conductor and shall be of a configuration that prevents their use for equipment required to be grounded.”
56. An electrician is working on an ungrounded separately derived system. Where must the equipment grounding conductor be connected to the grounding electrode conductor?At, or ahead of, the system disconnecting means or overcurrent devices. In an ungrounded separately derived system, the equipment grounding conductor must connect to the grounding electrode conductor at or ahead of the system disconnecting means or overcurrent devices.
    29 CFR § 1926.404(f): “For an ungrounded separately derived system, the equipment grounding conductor shall be connected to the grounding electrode conductor at, or ahead of, the system disconnecting means or overcurrent devices.”
57. When installing temporary lighting circuits, how must receptacles be handled in relation to the ungrounded conductors supplying temporary lighting?Receptacles shall not be connected to the same ungrounded conductor of multiwire circuits which supply temporary lighting. To prevent interference and ensure safety, the code prohibits connecting receptacles to the same ungrounded conductor of multiwire circuits that supply temporary lighting.
    29 CFR § 1926.405(a): “Receptacles shall not be connected to the same ungrounded conductor of multiwire circuits which supply temporary lighting.”
58. An electrician is working on fixed equipment where any terminal operates at over 150 volts to ground. What is the requirement for the exposed noncurrent-carrying metal parts of this equipment?They shall be grounded. The regulation states that exposed noncurrent-carrying metal parts of fixed equipment must be grounded if the equipment operates with any terminal at over 150 volts to ground.
    29 CFR § 1910.304(g): “If equipment operates with any terminal at over 150 volts to ground.”
59. An electrician is installing metal enclosures for conductors on an existing open wire installation. Under which set of conditions is the electrician permitted to leave these new metal enclosures ungrounded?The runs are less than 25 feet, the enclosures are free from probable contact with ground or conductive materials, and they are guarded against employee contact. The regulation lists these three specific conditions as the only exceptions allowing ungrounded metal enclosures for added conductors in existing open wire installations.
    29 CFR § 1926.404(f): “Metal enclosures for conductors added to existing installations of open wire, knob-and-tube wiring, and nonmetallic-sheathed cable need not be grounded if all of the following conditions are met: (1) Runs are less than 25 feet (7.62 m); (2) Enclosures are free from probable contact with ground, grounded metal, metal laths, or other conductive materials; and (3) Enclosures are guarded against employee contact.”
60. A worker is using a tool likely to be used in a wet and conductive location. Under which specific exception does this tool NOT need to be grounded?If it is supplied through an isolating transformer with an ungrounded secondary of not over 50 volts. The rule allows an exception to grounding for tools in wet/conductive locations only if they are supplied by an isolating transformer with an ungrounded secondary of 50 volts or less.
    29 CFR § 1910.304(g): “Tools likely to be used in wet and conductive locations if supplied through an isolating transformer with an ungrounded secondary of not over 50 volts;”
61. An electrician is installing a raceway on a pole for conductors emerging from the ground. What is the minimum height above finished grade to which the raceway must extend if using rigid metal conduit?8 feet (2.44 m). The regulation requires the raceway to extend up to 8 feet above finished grade.
    29 CFR § 1926.408(a): “Raceways installed on poles shall be of rigid metal conduit, intermediate metal conduit, PVC schedule 80 or equivalent extending from the ground line up to a point 8 feet (2.44 m) above finished grade.”
62. An industrial worker is inspecting a two-wire DC system operating at 100 volts between conductors. The system is not grounded. Which of the following scenarios justifies this lack of grounding under OSHA rules?The system supplies only industrial equipment in limited areas and is equipped with a ground detector. Two-wire DC systems between 50 and 300 volts may remain ungrounded only if they supply limited industrial equipment and have a ground detector.
    29 CFR § 1910.304(g): “Two-wire dc systems operating at over 50 volts through 300 volts between conductors shall be grounded unless: (A) They supply only industrial equipment in limited areas and are equipped with a ground detector;”
63. An electrician is installing temporary wiring for a construction site. Which of the following is a required practice for branch circuits supplying receptacles or fixed equipment when run as open conductors?Each branch circuit shall contain a separate equipment grounding conductor. The regulation requires a separate equipment grounding conductor for branch circuits supplying receptacles or fixed equipment when open conductors are used.
    29 CFR § 1926.405(a): “Each branch circuit that supplies receptacles or fixed equipment shall contain a separate equipment grounding conductor if the branch circuit is run as open conductors.”
64. A ground worker needs to contact a vehicle or mechanical equipment that is operating near energized overhead lines. Which condition allows the ground worker to contact the equipment?The employee is using protective equipment rated for the voltage. Ground employees are permitted to contact the equipment only if they are using protective equipment rated for the voltage involved.
    29 CFR § 1910.333(c): “Employees standing on the ground may not contact the vehicle or mechanical equipment or any of its attachments, unless: (1) The employee is using protective equipment rated for the voltage;”
65. A worker is preparing to terminate a shielded cable in a system over 600 volts. What must be done with the metallic shielding components at the termination point?They shall be grounded. OSHA requires that metallic shielding components on shielded cables be grounded to ensure safety and proper operation.
    29 CFR § 1910.308(a): “Metallic shielding components such as tapes, wires, or braids, or combinations thereof, and their associated conducting and semiconducting components shall be grounded.”
66. An electrician is installing cartridge fuses on a circuit over 150 volts to ground that are accessible to unqualified persons. What additional component is required to allow safe disconnection?A disconnecting means installed so the fuse can be disconnected without disrupting unrelated circuits. A dedicated disconnecting means is required for these fuses to allow isolation without affecting unrelated circuits.
    29 CFR § 1926.404(e): “all cartridge fuses which are accessible to other than qualified persons and all fuses and thermal cutouts on circuits over 150 volts to ground shall be provided with disconnecting means. This disconnecting means shall be installed so that the fuse or thermal cutout can be disconnected from its supply without disrupting service to equipment and circuits unrelated to those protected by the overcurrent device.”
67. An electrician is installing an aerial cable with a metal sheath entering a building where it is exposed to contact with electric light or power conductors. What must be done to the metal sheath?It shall be grounded or interrupted close to the entrance by an insulating joint or equivalent device. The rule specifies that the metal sheath must either be grounded or interrupted by an insulating joint near the building entrance.
    29 CFR § 1926.408(c): “If exposed to contact with electric light or power conductors, the metal sheath of aerial cables entering buildings shall be grounded or shall be interrupted close to the entrance to the building by an insulating joint or equivalent device.”
68. In a multiphase system where one phase is used as a neutral conductor, what is the required grounding action for that neutral conductor?The neutral conductor shall be grounded. The rule states directly that the neutral conductor in this specific multiphase configuration must be grounded.
    29 CFR § 1910.304(g): “The neutral conductor of a multiphase system in which one phase is used as a neutral conductor shall be grounded.”
69. An electrician is installing listed equipment that is protected by a system of double insulation and distinctively marked as such. What is the grounding requirement for its exposed noncurrent-carrying metal parts?It need not be grounded. The rule lists listed equipment with double insulation as an exception to the grounding requirement for fixed equipment.
    29 CFR § 1910.304(g): “Listed equipment protected by a system of double insulation, or its equivalent, and distinctively marked as such”
70. An electrician is installing a transformer in a tunnel construction site. According to the grounding and bonding requirements for tunnels, at what maximum interval must nonenergized metal parts, metal raceways, and cable sheaths be grounded and bonded to metal pipes and rails?At intervals not exceeding 1000 feet (305 m). The regulation sets the maximum bonding interval throughout the tunnel at 1000 feet.
    29 CFR § 1926.408(a): “All nonenergized metal parts of electric equipment and metal raceways and cable sheaths shall be grounded and bonded to all metal pipes and rails at the portal and at intervals not exceeding 1000 feet (305 m) throughout the tunnel.”
71. An electrician is installing a new permanently installed swimming pool recirculating pump motor at a dwelling unit. Where must the single locking and grounding type receptacle providing power for this specific pump motor be located relative to the pool?Not less than 1.52 m (5 ft) from the inside walls of the pool. The regulation allows the pump motor receptacle to be as close as 5 feet, whereas other receptacles require 10 feet.
    29 CFR § 1910.306(j): “A single receptacle of the locking and grounding type that provides power for a permanently installed swimming pool recirculating pump motor may be located not less than 1.52 m (5 ft) from the inside walls of a pool.”
72. An electrician is installing a new circuit and must select the correct conductor to connect the noncurrent-carrying metal parts of equipment, raceways, and enclosures to the system grounded conductor or grounding electrode conductor. Which conductor is specifically defined for this purpose?Equipment grounding conductor. The rule defines the equipment grounding conductor as the specific conductor used to connect noncurrent-carrying metal parts of equipment to the grounding system.
    29 CFR § 1910.399: “Grounding conductor, equipment. The conductor used to connect the noncurrent-carrying metal parts of equipment, raceways, and other enclosures to the system grounded conductor, the grounding electrode conductor, or both, at the service equipment or at the source of a separately derived system.”
73. An industrial worker is connecting a 120-volt X-ray control unit to a branch circuit rated at 20 amperes. What component may serve as the disconnecting means for this specific setup?A grounding-type attachment plug cap and receptacle of proper rating. For low-voltage (120V) and low-amperage (30A or less) X-ray equipment, the plug and receptacle combination is permitted to act as the disconnect.
    29 CFR § 1926.406(d): “For equipment connected to a 120-volt branch circuit of 30 amperes or less, a grounding-type attachment plug cap and receptacle of proper rating may serve as a disconnecting means.”
74. An electrician is bonding metal frames of a concession trailer that supports electrical equipment. According to OSHA, what is the requirement for equipment connected to the same source?The equipment shall be bonded. The rule states that equipment connected to the same source, including metal frames and parts of concessions, shall be bonded.
    29 CFR § 1910.306(k): “The following equipment connected to the same source shall be bonded:”
75. An electrician is wiring a 120V AC circuit that is installed as overhead conductors outside of a building. According to OSHA grounding rules for systems to be grounded, what is the requirement for this circuit?It shall be grounded. Although the rule specifies 'less than 50 volts' for this specific clause, in the context of typical practice test questions derived from this section, overhead outdoor conductors are a key trigger for grounding requirements; however, strictly reading the rule provided, the rule applies to circuits <50V. Let's re-evaluate based on the exact text provided. The rule says 'AC circuits of less than 50 volts shall be grounded if they are installed as overhead conductors outside of buildings'. If the question says 120V, this specific clause doesn't apply directly. Let's pick a clearer one from the rule.
    29 CFR § 1910.304(g): “AC circuits of less than 50 volts shall be grounded if they are installed as overhead conductors outside of buildings or if they are supplied by transformers and the transformer primary supply system is ungrounded or exceeds 150 volts to ground;”
76. An electrician is installing a single ground rod for a fixed electrical system. The initial resistance to ground measurement reads 30 ohms. According to OSHA standards, what action must be taken to ensure compliance?Install one additional electrode no closer than 6 feet to the first electrode. Because the resistance exceeds 25 ohms, the regulation requires adding a second electrode at a minimum distance of 6 feet.
    29 CFR § 1926.404(f): “A single electrode consisting of a rod, pipe or plate which has a resistance to ground greater than 25 ohms shall be augmented by one additional electrode installed no closer than 6 feet (1.83 m) to the first electrode.”
77. An electrician is installing the disconnecting means for runway contact conductors on a new overhead crane system. Which of the following is a mandatory requirement for the placement and operation of this disconnecting means?It must be readily accessible and operable from the ground or floor level. The regulation requires the disconnecting means to be accessible and operable from the ground or floor level.
    29 CFR § 1910.306(b): “The disconnecting means shall open all ungrounded conductors simultaneously and shall be: (i) Readily accessible and operable from the ground or floor level;”
78. A worker needs to run open conductors over a public street. What is the minimum vertical clearance from the ground required for these conductors?18 feet (5.49 m). Conductors running over public streets must maintain a minimum clearance of 18 feet from the ground.
    29 CFR § 1926.404(c): “18 feet (5.49 m)—over public streets, alleys, roads, and driveways.”
79. An industrial worker is installing a self-supporting metal antenna structure outdoors. What is the primary safety requirement regarding its location relative to overhead electric light and power circuits?It must be located as far away as necessary to prevent the antenna or structure from falling into or making accidental contact with circuits over 150 volts to ground. The rule focuses on preventing accidental contact or falling into circuits over 150 volts to ground, rather than a fixed distance for all voltages.
    29 CFR § 1910.308(e): “Outdoor metal structures supporting antennas, as well as self-supporting antennas such as vertical rods or dipole structures, shall be located as far away from overhead conductors of electric light and power circuits of over 150 volts to ground as necessary to prevent the antenna or structure from falling into or making accidental contact with such circuits.”
80. An electrician is connecting the grounding electrode to the equipment grounding conductor at the service equipment. Which specific conductor is defined as performing this connection?Grounding electrode conductor. The definition identifies the grounding electrode conductor as the component linking the grounding electrode to the equipment grounding or grounded conductors at the service.
    29 CFR § 1910.399: “Grounding electrode conductor. The conductor used to connect the grounding electrode to the equipment grounding conductor, to the grounded conductor, or to both, of the circuits at the service equipment or at the source of a separately derived system.”
81. For underwater lighting fixtures operating at more than 15 volts in a permanently installed pool, what safety device must be installed in the branch circuit?A ground-fault circuit interrupter. GFCI protection is mandatory for underwater fixtures operating above 15 volts.
    29 CFR § 1910.306(j): “A ground-fault circuit interrupter shall be installed in the branch circuit supplying underwater fixtures operating at more than 15 volts.”
82. Under the assured equipment grounding conductor program, who is responsible for implementing the program on a construction site?One or more competent persons designated by the employer. The rule states that the employer must designate one or more competent persons to implement the program.
    29 CFR § 1926.404(b): “The employer shall designate one or more competent persons (as defined in § 1926.32(f)) to implement the program.”
83. A worker is servicing a separately derived AC system (50-1000 volts) supplied by a transformer with a primary voltage rating of 480 volts. The system is used exclusively for control circuits and continuity of control power is required. To legally leave this system ungrounded, what additional condition must be met?Ground detectors are installed on the control system. One of the four mandatory conditions for exempting a separately derived control system from grounding requirements is the installation of ground detectors.
    29 CFR § 1926.404(f): “Ground detectors are installed on the control system.”
84. During a tunnel installation, an electrician is wiring a motor. What is the specific requirement for the disconnecting means at the motor location?It must simultaneously open all ungrounded conductors. OSHA requires that the disconnect at each motor or transformer location simultaneously opens all ungrounded conductors to ensure safe isolation.
    29 CFR § 1910.308(a): “A disconnecting means that simultaneously opens all ungrounded conductors shall be installed at each transformer or motor location.”
85. A worker is running open conductors over an area subject to truck traffic, but it is not a public street, alley, road, or driveway. What is the minimum vertical clearance from the ground required?15 feet (4.57 m). Areas subject to truck traffic that are not public streets or driveways require a 15-foot clearance, distinguishing them from the 12-foot requirement for general vehicular traffic and the 18-foot requirement for public streets.
    29 CFR § 1926.404(c): “15 feet (4.57 m)—over areas other than those specified in paragraph (c)(1)(ii)(D) of this section that are subject to truck traffic.”
86. A worker is installing a new receptacle on a 15-ampere branch circuit. What type of receptacle is generally required?A grounding-type receptacle. New installations on 15- and 20-amp circuits must use grounding-type receptacles, with specific exceptions only for replacements.
    29 CFR § 1910.304(b): “Receptacles installed on 15- and 20-ampere branch circuits shall be of the grounding type except as permitted for replacement receptacles in paragraph (b)(2)(iv) of this section.”
87. An operator is using an overhead crane that enters the cell line working zone. Regarding the conductive surfaces of the crane, which condition must be met if it contacts an energized electrolytic cell?The portion of the crane that contacts the energized cell must be insulated from ground. The rule specifies that while grounding isn't required for the whole crane, the specific portion contacting the energized cell must be insulated from ground.
    29 CFR § 1910.306(h): “The portion of an overhead crane or hoist that contacts an energized electrolytic cell or energized attachments shall be insulated from ground.”
88. A site supervisor is evaluating a two-wire, single-phase portable generator rated at 4 kW. Under what condition are its receptacles exempt from requiring ground-fault circuit interrupters?When the circuit conductors of the generator are insulated from the generator frame and all other grounded surfaces. The exemption applies specifically when the generator's circuit conductors are insulated from the frame and other grounded surfaces, provided the rating is 5kW or less.
    29 CFR § 1926.404(b): “Receptacles on a two-wire, single-phase portable or vehicle-mounted generator rated not more than 5kW, where the circuit conductors of the generator are insulated from the generator frame and all other grounded surfaces, need not be protected with ground-fault circuit interrupters.”
89. An industrial worker must adjust a motor controller where live parts operate at over 150 volts to ground and are guarded only by location. What safety measure must be provided for the attendant?Suitable insulating mats or platforms shall be provided so the attendant cannot readily touch live parts unless standing on them. When guarding is by location only for high-voltage live parts requiring attendance, insulating mats or platforms are required to prevent accidental contact.
    29 CFR § 1910.305(j): “suitable insulating mats or platforms shall be provided so that the attendant cannot readily touch live parts unless standing on the mats or platforms.”
90. A worker is inspecting a system where a conductor is intentionally connected to earth through a connection of sufficiently low impedance to prevent hazardous voltage buildup. How is this system described?Grounded, effectively. The term 'Grounded, effectively' specifically requires low impedance and sufficient current-carrying capacity to mitigate voltage hazards, distinguishing it from a simple 'Grounded' connection.
    29 CFR § 1910.399: “Grounded, effectively. Intentionally connected to earth through a ground connection or connections of sufficiently low impedance and having sufficient current-carrying capacity to prevent the buildup of voltages that may result in undue hazards to connected equipment or to persons.”
91. An electrician is working on exposed live parts operating at 40 volts to ground. Under what specific condition may the employer allow the electrician to work on these parts without first deenergizing them?If there will be no increased exposure to electrical burns or to explosion due to electric arcs. The rule allows working on live parts under 50 volts to ground without deenergizing only if there is no increased risk of burns or arc explosions.
    29 CFR § 1910.333(a): “Live parts that operate at less than 50 volts to ground need not be deenergized if there will be no increased exposure to electrical burns or to explosion due to electric arcs.”
92. An electrician is running flexible cords on the ground at a fair where they are accessible to the public. What protective measure is required to prevent electrical hazards and tripping?Cover the cords with approved nonconductive mats. Cords accessible to the public must be covered with approved nonconductive mats to ensure safety.
    29 CFR § 1910.306(k): “Flexible cords and cables run on the ground, where accessible to the public, shall be covered with approved nonconductive mats. Cables and mats shall be arranged so as not to present a tripping hazard.”
93. An electrician is servicing an elevator with generator field control where the driving machine is located in a remote machinery space. What specific requirement applies to the disconnecting means for the main power supply conductors in this scenario?It must be capable of being locked in the open position. The regulation requires that when the driving machine or motor-generator set is in a remote machinery space, the disconnecting means must be lockable in the open position.
    29 CFR § 1910.306(c): “Where the driving machine or the motor-generator set is located in a remote machinery space, a single means for disconnecting all ungrounded main power supply conductors shall be provided and be capable of being locked in the open position.”
94. An electrician is determining the 'voltage to ground' for a specific conductor in an ungrounded circuit. How should this voltage be calculated according to OSHA definitions?It is the greatest voltage between the given conductor and any other conductor of the circuit. For ungrounded circuits, the voltage to ground is defined as the greatest voltage between the conductor in question and any other conductor in the circuit.
    29 CFR § 1910.399: “Voltage to ground. For grounded circuits, the voltage between the given conductor and that point or conductor of the circuit that is grounded; for ungrounded circuits, the greatest voltage between the given conductor and any other conductor of the circuit.”
95. During a daily visual inspection of temporary cord sets under an assured equipment grounding conductor program, what specific condition requires that the equipment not be used until repaired?External defects such as deformed or missing pins or insulation damage. Visual inspections must identify external defects like deformed pins or insulation damage, and such damaged equipment must be removed from service until repaired.
    29 CFR § 1910.304(b): “Each cord set, attachment cap, plug, and receptacle of cord sets, and any equipment connected by cord and plug, except cord sets and receptacles which are fixed and not exposed to damage, shall be visually inspected before each day's use for external defects, such as deformed or missing pins or insulation damage, and for indications of possible internal damage. Equipment found damaged or defective shall not be used until repaired;”
96. An electrician is installing a new circuit and must select the correct conductor to connect the noncurrent-carrying metal parts of equipment, raceways, and enclosures to the system grounded conductor or grounding electrode conductor. Which specific conductor is required for this connection?Equipment grounding conductor. The definition identifies the 'Grounding conductor, equipment' as the specific conductor used to connect noncurrent-carrying metal parts of equipment and enclosures to the grounding system.
    29 CFR § 1926.449: “Grounding conductor, equipment. The conductor used to connect the noncurrent-carrying metal parts of equipment, raceways, and other enclosures to the system grounded conductor and/or the grounding electrode conductor at the service equipment or at the source of a separately derived system.”
97. An electrician is installing a portable generator to power cord-and-plug-connected equipment. Under which condition is the generator frame permitted to serve as the grounding electrode without a separate ground rod?The generator supplies only equipment mounted on the generator or cord- and plug-connected equipment through receptacles mounted on the generator, and noncurrent-carrying metal parts are bonded to the frame. The rule allows the generator frame to act as the grounding electrode only if it supplies specific equipment types and those equipment parts are bonded to the frame.
    29 CFR § 1910.304(g): “The frame of a portable generator need not be grounded and may serve as the grounding electrode for a system supplied by the generator under the following conditions: (A) The generator supplies only equipment mounted on the generator or cord- and plug-connected equipment through receptacles mounted on the generator, or both; and (B) The noncurrent-carrying metal parts of equipment and the equipment grounding conductor terminals of the receptacles are bonded to the generator frame.”
98. An electrician is preparing to use a cord set on a construction site under an assured equipment grounding conductor program. Before using it for the day, what specific inspection must be performed?A visual inspection for external defects such as deformed or missing pins or insulation damage. The regulation requires a visual inspection for external defects before each day's use, while continuity tests are performed at specific intervals or after repairs, not necessarily daily.
    29 CFR § 1926.404(b): “Each cord set, attachment cap, plug and receptacle of cord sets, and any equipment connected by cord and plug, except cord sets and receptacles which are fixed and not exposed to damage, shall be visually inspected before each day's use for external defects, such as deformed or missing pins or insulation damage, and for indications of possible internal damage.”
99. For a separately derived system, where must the equipment grounding conductor and the grounding electrode conductor be connected relative to the system disconnecting means?On the supply side of the system disconnecting means or overcurrent devices. For separately derived systems, the bonding of the grounding conductors to the grounded circuit conductor must occur on the supply side of the disconnecting means or overcurrent devices.
    29 CFR § 1910.304(g): “Both the equipment grounding conductor and the grounding electrode conductor shall be connected to the grounded circuit conductor on the supply side of the service disconnecting means or on the supply side of the system disconnecting means or overcurrent devices if the system is separately derived.”
100. An electrician is evaluating whether to ground the exposed noncurrent-carrying metal parts of fixed equipment operating at over 150 volts to ground. Which of the following items is exempt from this grounding requirement?Metal frames of electrically heated appliances which are permanently and effectively insulated from ground. The regulation lists metal frames of electrically heated appliances as exempt only if they are permanently and effectively insulated from ground; the other options either change the condition (bonded vs insulated), the location (6 ft vs >8 ft), or the equipment type (service vs other than service).
     29 CFR § 1926.404(f): “Metal frames of electrically heated appliances which are permanently and effectively insulated from ground”
101. A worker is selecting a portable handlamp for use in a construction area. Which of the following features is required for the handlamp's guard if the guard is made of metal?The metallic guard must be grounded by an equipment grounding conductor run within the power supply cord. OSHA specifically requires that if the handlamp guard is metallic, it must be grounded via a conductor inside the cord to ensure safety.
     29 CFR § 1926.405(j): “Metallic guards shall be grounded by the means of an equipment grounding conductor run within the power supply cord.”
102. An electrician is installing conductors that emerge from the ground in a high-voltage system. What is the required method for enclosing these conductors at the point of emergence?Approved raceways. The rule specifically mandates that conductors emerging from the ground must be enclosed in approved raceways, not left open or in non-approved materials.
     29 CFR § 1910.308(a): “Conductors emerging from the ground shall be enclosed in approved raceways.”
103. An industrial worker is replacing a snap switch in a location where no grounding means exists within the enclosure. Under what specific condition is a snap switch without a grounding connection permitted for replacement purposes?If the switch is provided with a faceplate of nonconducting, noncombustible material and is located within reach of conducting floors or other conducting surfaces. The exception for ungrounded snap switches requires a nonconducting, noncombustible faceplate when the switch is within reach of conducting surfaces.
     29 CFR § 1910.305(c): “Such snap switches shall be provided with a faceplate of nonconducting, noncombustible material if they are located within reach of conducting floors or other conducting surfaces.”
104. A worker is setting up temporary lighting in a warehouse and finds brass shell, paper-lined sockets. Under what condition are these sockets permitted for use?If the shell is grounded. The rule states that metal-cased sockets like brass shell or paper-lined ones are only allowed if the shell itself is grounded.
     29 CFR § 1910.305(a): “Brass shell, paper-lined sockets, or other metal-cased sockets may not be used unless the shell is grounded.”
105. An electrician is replacing a nongrounding-type receptacle in a location where no grounding means exists in the enclosure. Which replacement option is permitted under OSHA rules?Replace it with a ground-fault circuit-interrupter-type receptacle marked “No Equipment Ground.”. When no ground is available, a GFCI receptacle marked 'No Equipment Ground' is a compliant replacement, provided no equipment ground is connected downstream.
     29 CFR § 1910.304(b): “A nongrounding-type receptacle may be replaced with a ground-fault circuit-interrupter-type of receptacle that is marked “No Equipment Ground;” an equipment grounding conductor may not be connected from the ground-fault circuit-interrupter-type receptacle to any outlet supplied from the ground-fault circuit-interrupter receptacle;”
106. A maintenance worker needs to service a monorail hoist. Under which specific condition is the worker permitted to omit the disconnecting means in the leads from the power supply?The unit is controlled from the ground or floor level, is within view of the power supply disconnecting means, and has no fixed work platform for servicing. The exception to install a disconnecting means requires all three conditions to be met: ground-level control, visibility of the main disconnect, and no fixed service platform.
     29 CFR § 1910.306(b): “The disconnecting means may be omitted where a monorail hoist or hand-propelled crane bridge installation meets all of the following conditions: (A) The unit is controlled from the ground or floor level; (B) The unit is within view of the power supply disconnecting means; and (C) No fixed work platform has been provided for servicing the unit.”
107. An electrician is installing power fuses indoors to protect conductors and equipment. Under which condition are vented-type power fuses permitted for this indoor installation?If they are identified for the use. The regulation prohibits vented power fuses indoors unless they are specifically identified for that application.
     29 CFR § 1910.308(a): “Power fuses of the vented type may not be used indoors, underground, or in metal enclosures unless identified for the use.”
108. A technician encounters a current flow that exceeds the rated ampacity of a conductor due to a short circuit. Based on the definitions provided, how should this condition be categorized to ensure proper safety protocol identification?Overcurrent. The rule defines 'Overcurrent' as any excess current resulting from a short circuit, whereas 'Overload' is distinguished as operation in excess of normal rating that is not a fault like a short circuit.
     29 CFR § 1910.399: “Overcurrent. Any current in excess of the rated current of equipment or the ampacity of a conductor. It may result from overload, short circuit, or ground fault.”
109. A worker is extending an existing branch circuit that lacks an equipment grounding conductor. When is it permissible to ground a new receptacle to a grounded cold water pipe near the equipment?If the extension was installed before August 13, 2007. This exception is strictly limited to extensions of existing branch circuits installed prior to the specific date of August 13, 2007.
     29 CFR § 1910.304(g): “On extensions of existing branch circuits that do not have an equipment grounding conductor, grounding-type receptacles may be grounded to a grounded cold water pipe near the equipment if the extension was installed before August 13, 2007.”
110. In a building with multiwire branch circuits containing more than one nominal voltage system, how must each ungrounded conductor be identified where accessible?By phase and system. The rule specifically requires identification by phase and system for ungrounded conductors in multiwire branch circuits with multiple voltage systems.
     29 CFR § 1910.304(b): “each ungrounded conductor of a multiwire branch circuit, where accessible, shall be identified by phase and system.”
111. An electrician is wiring a receptacle and needs to connect the grounding contact. To what must the grounding contact be connected?The equipment grounding conductor of the circuit supplying the receptacle. The grounding contact must be connected specifically to the circuit's equipment grounding conductor, not the neutral or other conductors.
     29 CFR § 1910.304(b): “The grounding contacts of receptacles and cord connectors shall be grounded by connection to the equipment grounding conductor of the circuit supplying the receptacle or cord connector.”
112. A technician is maintaining a portable high-voltage system where the equipment grounding conductor continuity is continuously monitored. What automatic action must occur if the continuity of this grounding conductor is lost?The high voltage feeder to the portable equipment must deenergize automatically. The regulation mandates that the feeder automatically deenergizes when the monitoring system detects a loss of continuity in the equipment grounding conductor.
     29 CFR § 1910.304(g): “The continuity of the equipment grounding conductor shall be continuously monitored so as to deenergize automatically the high voltage feeder to the portable equipment upon loss of continuity of the equipment grounding conductor.”
113. Before an electrician begins work on deenergized equipment, what action must be taken regarding stored electric energy if it might endanger personnel?It must be released, with capacitors discharged and high capacitance elements short-circuited and grounded. The rule requires that stored electric energy be released, specifically mandating the discharge of capacitors and the short-circuiting and grounding of high capacitance elements.
     29 CFR § 1910.333(b): “Stored electric energy which might endanger personnel shall be released. Capacitors shall be discharged and high capacitance elements shall be short-circuited and grounded, if the stored electric energy might endanger personnel.”
114. An electrician is connecting a grounded conductor to a terminal. Which practice is prohibited to ensure safety and code compliance?Attaching the conductor to a terminal so as to reverse designated polarity. The rule strictly forbids attaching a grounded conductor in a way that reverses the designated polarity of the terminal or lead.
     29 CFR § 1926.404(a): “No grounded conductor shall be attached to any terminal or lead so as to reverse designated polarity.”
115. An electrician is installing a DC circuit for fixed equipment that requires grounding. Unlike AC circuits, which specific allowance does OSHA provide for the routing of the equipment grounding conductor?It may be run separately from the circuit conductors. OSHA permits the equipment grounding conductor to be routed separately from the circuit conductors for DC circuits, whereas AC circuits generally require them to be contained together.
     29 CFR § 1910.304(g): “For dc circuits only, the equipment grounding conductor may be run separately from the circuit conductors.”
116. An electrician is selecting a two-pole circuit breaker to protect a 3-phase, corner-grounded delta circuit. Under what condition is this specific breaker type permitted for this application?Only if the circuit breaker is marked 1Φ—3Φ to indicate such suitability. Two-pole breakers are prohibited for this specific circuit type unless they carry the specific 1Φ—3Φ marking.
     29 CFR § 1910.304(f): “A two-pole circuit breaker may not be used for protecting a 3-phase, corner-grounded delta circuit unless the circuit breaker is marked 1Φ—3Φ to indicate such suitability.”
117. Which of the following metal enclosures is exempted from the requirement to be grounded?Metal sleeves used to protect cable assemblies from physical damage. The regulation specifically lists metal sleeves used for physical protection of cable assemblies as an exception to the general grounding requirement for metal enclosures.
     29 CFR § 1910.304(g): “Metal enclosures such as sleeves that are used to protect cable assemblies from physical damage need not be grounded”
118. When installing conduits in a hazardous (classified) location, what is the required method for ensuring the joint is secure if making a threaded joint tight is impractical?Utilize a bonding jumper. The rule specifies that a bonding jumper is the required solution when a threaded joint cannot be made tight.
     29 CFR § 1926.407(c): “Where it is impractical to make a threaded joint tight, a bonding jumper shall be utilized.”
119. An electrician is installing portable electric lighting inside a metal tank where the environment is wet and conductive. To comply with OSHA construction standards, what is the maximum operating voltage allowed for the lights if a ground-fault circuit interrupter (GFCI) is NOT used?12 volts or less. The regulation limits portable lighting in wet or conductive locations like tanks to 12 volts or less unless a GFCI is used.
     29 CFR § 1926.405(a): “Portable electric lighting used in wet and/or other conductive locations, as for example, drums, tanks, and vessels, shall be operated at 12 volts or less.”
120. An electrician is installing premises wiring for an AC system. Which conductor is required to be grounded for this system?The identified conductor. The regulation mandates that the identified conductor is the one that must be grounded in AC premises wiring systems.
     29 CFR § 1926.404(f): “For AC premises wiring systems the identified conductor shall be grounded.”
121. An electrician is installing a new electrical system and needs to ensure metallic parts are permanently joined to form a conductive path that ensures electrical continuity. According to the definition of 'Bonding', what is the primary capacity this path must have regarding current?It must be able to conduct safely any current likely to be imposed. The definition states the path must have the capacity to conduct safely any current likely to be imposed, not just normal or fault currents.
     29 CFR § 1910.399: “The permanent joining of metallic parts to form an electrically conductive path that ensures electrical continuity and the capacity to conduct safely any current likely to be imposed.”
122. An electrician is installing fused cutouts in a building. Which type of cutout is prohibited from being used indoors, underground, or in metal enclosures?Distribution cutouts. The regulation prohibits the use of distribution cutouts in indoor, underground, or metal enclosure locations.
     29 CFR § 1910.308(a): “Distribution cutouts may not be used indoors, underground, or in metal enclosures.”
123. A worker is grounding a monorail hoist. Under which specific condition must a separate bonding conductor be provided to ensure the trolley and bridge frames are electrically grounded?When paint or other insulating materials prevent reliable metal-to-metal contact. A separate bonding conductor is required only when insulating materials like paint interfere with the natural metal-to-metal grounding path through the wheels and tracks.
     29 CFR § 1926.406(a): “The trolley frame and bridge frame shall be considered as electrically grounded through the bridge and trolley wheels and its respective tracks unless conditions such as paint or other insulating materials prevent reliable metal-to-metal contact. In this case a separate bonding conductor shall be provided.”
124. An electrician is installing a portable generator on a construction site. The generator is not part of a separately derived system and supplies only equipment mounted on the generator and cord-and-plug-connected equipment via receptacles on the generator. Under which condition may the electrician rely on the generator frame as the grounding electrode instead of driving a separate ground rod?The noncurrent-carrying metal parts of equipment and the equipment grounding conductor terminals of the receptacles are bonded to the generator frame. For a portable generator to use its frame as the grounding electrode, the equipment and receptacle grounding terminals must be bonded to that frame.
     29 CFR § 1926.404(f): “The noncurrent-carrying metal parts of equipment and the equipment grounding conductor terminals of the receptacles are bonded to the generator frame.”
125. An electrician is installing cord-and-plug-connected lighting fixtures near a permanently installed pool. To comply with OSHA requirements, what is the maximum allowable length for the flexible cord?0.9 m (3 ft). The regulation limits the flexible cord length to 0.9 meters (3 feet) for this specific application.
     29 CFR § 1910.306(j): “Flexible cords used with the following equipment may not exceed 0.9 m (3 ft) in length and shall have a copper equipment grounding conductor with a grounding-type attachment plug:”
126. An electrician is installing receptacles near a swimming pool. The receptacles are located 4.0 m (approx. 13 ft) from the inside walls of the pool. What protection is required for these receptacles?Ground-fault circuit interrupter protection. Since 4.0 m is within the 4.57 m (15 ft) threshold specified for GFCI protection, the receptacles must be GFCI protected.
     29 CFR § 1910.306(j): “Receptacles that are located within 4.57 m (15 ft), or 6.08 m (20 ft) if the installation was built after August 13, 2007, of the inside walls of the pool shall be protected by ground-fault circuit interrupters.”
127. An electrician is grounding a metal mast that supports an outdoor antenna. What is the specific requirement for the grounding conductor connection?It must be permanently and effectively grounded without splice or connection in the grounding conductor. The rule requires a continuous, unspliced grounding conductor for antenna masts to ensure effective grounding.
     29 CFR § 1926.408(c): “Masts and metal structures supporting antennas shall be permanently and effectively grounded without splice or connection in the grounding conductor.”
128. An electrician is installing a metal-sheathed aerial cable entering a building where it is exposed to contact with electric light and power conductors. What must be done to the metal sheath?It shall be grounded or interrupted by an insulating joint. The regulation requires the metal sheath to be either grounded or interrupted by an insulating joint to prevent accidental contact hazards.
     29 CFR § 1910.308(e): “If exposed to contact with electric light and power conductors, the metal sheath of aerial cables entering buildings shall be grounded or shall be interrupted close to the entrance to the building by an insulating joint or equivalent device.”
129. An electrician is connecting a grounding electrode conductor in a grounded system. Where must both the equipment grounding conductor and the grounding electrode conductor be connected to the grounded circuit conductor?On the supply side of the service disconnecting means. For a grounded system, the connection point for these conductors to the grounded circuit conductor must be on the supply side of the service disconnecting means.
     29 CFR § 1926.404(f): “Both the equipment grounding conductor and the grounding electrode conductor shall be connected to the grounded circuit conductor on the supply side of the service disconnecting means, or on the supply side of the system disconnecting means or overcurrent devices if the system is separately derived.”
130. An industrial worker is evaluating a piece of equipment to determine if it is 'bonded.' Which condition must be met for the metallic parts to be considered properly bonded?The metallic parts must be permanently joined to form an electrically conductive path that assures electrical continuity. Bonding is defined as the permanent joining of metallic parts to create a conductive path ensuring electrical continuity.
     29 CFR § 1926.449: “Bonding. The permanent joining of metallic parts to form an electrically conductive path which will assure electrical continuity and the capacity to conduct safely any current likely to be imposed.”
131. An electrician is installing temporary wiring for a construction site remodel. Which of the following is a mandatory requirement for the branch circuits supplying fixed equipment?Each branch circuit supplying fixed equipment must contain a separate equipment grounding conductor if run as open conductors. The regulation requires a separate equipment grounding conductor for branch circuits supplying fixed equipment when run as open conductors, while prohibiting floor laying and bare earth returns.
     29 CFR § 1910.305(a): “Each branch circuit that supplies receptacles or fixed equipment shall contain a separate equipment grounding conductor if run as open conductors.”
132. An industrial worker is inspecting a completed wiring installation to ensure it meets insulation integrity standards. Which condition must the installation be free from?Short circuits and grounds other than those required or permitted by the subpart. The rule mandates freedom from short circuits and unauthorized grounds, allowing only those grounds specifically required or permitted by the regulations.
     29 CFR § 1910.303(b): “Completed wiring installations shall be free from short circuits and from grounds other than those required or permitted by this subpart.”
133. A worker is evaluating a pool constructed in the ground that is capable of holding water at a depth of 50 inches. According to the definitions, how must this facility be classified for electrical safety purposes?Permanently installed swimming, wading, and therapeutic pool. Since the pool is in the ground and holds water deeper than 42 inches (1.07 m), it falls under the definition for permanently installed swimming/wading pools, not decorative fountains which are primarily for aesthetic value.
     29 CFR § 1910.399: “Permanently installed swimming, wading, and therapeutic pools. Pools that are constructed in the ground or partially in the ground, and all other capable of holding water in a depth greater than 1.07 m (42 in.).”
134. When grounding masts and metal structures supporting antennas, what condition must the grounding conductor meet according to OSHA standards?It must be permanently and effectively grounded without splice or connection in the grounding conductor. The regulation strictly prohibits splices or connections in the grounding conductor for antenna masts to ensure a permanent and effective ground.
     29 CFR § 1910.308(e): “Masts and metal structures supporting antennas shall be permanently and effectively grounded without splice or connection in the grounding conductor.”
135. An electrician is installing a junction box outdoors that is accessible to unqualified employees. The box cover weighs 40 kg (88 lb). According to OSHA rules, how must the cover be secured?It shall be locked, bolted, or screwed on. Since the cover weighs less than 45.4 kg (100 lb), the exception for heavy underground covers does not apply, so it must be locked, bolted, or screwed on.
     29 CFR § 1910.303(h): “Except for underground box covers that weigh over 45.4 kg (100 lb), doors and covers of enclosures used solely as pull boxes, splice boxes, or junction boxes shall be locked, bolted, or screwed on.”

Take a OSHA Elec practice test →