Response: The provision in question, 29 CFR 1910.303(g)(2)(i), generally requires “live parts of electric equipment operating at 50 volts or more” to be “guarded against accidental contact by use of approved cabinets or other forms of approved enclosures” or by other specified means.
What is the purpose of protecting electrical equipment with exposed parts operating at 50 volts or more?
To avoid the risk of accidental shock, live electrical components operating at 50 volts or more must be guarded with covers or other permanent barriers to prevent accidental contact by workers and their tools.
Is 50 volts high voltage?
Voltages over approximately 50 volts can usually cause dangerous amounts of current to flow through a human being who touches two points of a circuit, so safety standards are more restrictive around such circuits. In automotive engineering, high voltage is defined as voltage in range 30 to 1000 VAC or 60 to 1500 VDC.
What is the purpose of guarding of live parts?
(B) Prevent Physical Damage.
In locations where electrical equipment is likely to be exposed to physical damage, enclosures or guards shall be so arranged and of such strength as to prevent such damage.
ANSWER: According to OSHA’s 29 CFR 1910.333(a)(1), working on live parts that operate above 50 volts is allowable ONLY when the employer “can demonstrate that de-energizing introduces additional or increased hazards or is infeasible due to equipment design or operational limitations.”
What is the purpose of guarding electrical equipment with exposed parts operating at 50 V or more quizlet?
Live parts of electrical equipment operating at 50 volts or more may be guarded against accidental contact by putting them at an elevation of eight feet or more above the floor or other working surface and installed so as to exclude unqualified persons.
What is the specific safety purpose for requiring all holes in an electrical box or cabinet be covered?
Another reason you need to cover unused openings is that it keeps the interior of the electrical equipment from being exposed to the dirt, dust and other contaminates you may have at your facility. Allowing the interior of a circuit breaker panel to become dirty could cause additional safety issues.
Is 50 volts considered low voltage?
The International Electrotechnical Commission Standard IEC 61140:2016 defines Low voltage as 0 to 1000 V a.c. rms or 0 to 1500 V d.c. Other standards such as IEC 60038 defines supply system low voltage as voltage in the range 50 to 1000 V ac or 120 to 1500 V dc in IEC Standard Voltages which defines power distribution …
Why do we use High Voltage?
The primary reason that power is transmitted at high voltages is to increase efficiency. As electricity is transmitted over long distances, there are inherent energy losses along the way. … The higher the voltage, the lower the current. The lower the current, the lower the resistance losses in the conductors.
What happens if the voltage is too high?
The amount of current in a circuit depends on the voltage supplied: if the voltage is too high, then the wire may melt and the light bulb would have “burned out real time”. Similarly other electrical devices may stop working, or may even burst into flames if an overvoltage is delivered to the circuit.
What does exposed live parts mean?
Exposed (as applied to live parts) – Capable of being inadvertently touched or approached. nearer than a safe distance by a person. It is applied to parts that are not suitably guarded, isolated, or insulated. (
What are the three requirements for guarding of live parts?
110.27 Guarding of Live Parts
- (A) Live Parts Guarded Against Accidental Contact. …
- (B) Prevent Physical Damage. …
- (C) Warning Signs.
Who is required to ensure that electrical equipment is free from recognized hazards that are likely to cause death or serious physical harm?
The General Duty Clause is found in Section 5(a)(1) of the Occupational Safety and Health Act of 1970, and requires that “each employer shall furnish to each of his employees employment and a place of employment which are free from recognized hazards that are causing or are likely to cause death or serious physical …
When exposed energized parts are present safe electrical work practices require establishing?
When exposed energized parts are present, safe electrical work practices require establishing two approach boundaries to prevent electric shock. Before crossing these boundaries and moving closer to energized parts, workers need increasing levels of qualifications, protective equipment and permits.
What is the minimum safe working distance from exposed electrical conductors?
Under Table R-6, the minimum approach distance for a 25 kV system is 2 feet, 4 inches for phase-to-ground exposures, and 2 feet, 7 inches for phase-to-phase exposures.
What tools must not be used around exposed energized lines?
When an employee performs work within reaching distance of exposed energized parts of equipment, the employer shall ensure that the employee removes or renders nonconductive all exposed conductive articles, such as keychains or watch chains, rings, or wrist watches or bands, unless such articles do not increase the …