LVQ Safety

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Identify and explain the physiological hazards of electricity.

" 1-8 mA = mild shock 8-15 mA = painful shock 15-20 mA = painful shock (""can't let go"" level) with some involuntary muscle reaction potentially causing cuts, bumps, or falls in the affected individual 20-75 mA = painful shock with loss of breathing control 100 mA and above = complete loss of muscle control and will stop the heart. Source: Site Electrical Safe Practices 1.) Shock - when a person's body completes the current path between two energized conductors of an electrical circuit or between an energized conductor and a grounded surface or object. The effects of an electrical shock can vary from a slight tingle to immediate cardiac arrest. 2.) Burns - the most common shock related injury. An electrical accident can result in an electrical burn, arc burn, thermal contact burn or a combination. They are among the most serious burns and require immediate medical attention. They occur when an electric current flows through tissue or bone, generating heat that causes tissue damage. The body cannot dissipate the heat generated by current flowing through the resistance of tissue, therefore burns occur. 3.) Arc Flash - the electrical arc-flash is not voltage sensitive but is more a product of short-cicuit current and clearing time or arc duration. In some cases, it is possible to generate higher arc energy from a low-voltage source than from a high-voltage source. The damage from arc flash results in burns, potentially severe. 4.) Arc Blast - the rapid expansion of the air caused by an electrical arc. This occurrence is referred to as an electrical arc-blast or explosion. The pressures from an arc are developed from two sources, the expansion of the metal in boiling and vaporizing, and the heating of the air by passage of the arc through it. Copper expands by a factor of 67,000 times when it vaporizes. This accounts for the expulsion of near-vaporized droplets of molten metal from an arc."

Explain the difference between an arcing and bolted fault.

"A bolted fault passes through normally conductive material. An arcing fault is one that starts and is maintained through an air gap. Bolted fault currents have much higher current levels because there is less resistance. Arcing faults can be intermittent."

Demonstrate the appropriate response to a tripped LV fuse or circuit breaker.

1. Determine the source of the overcurrent condition (ie, wiring defect, equipment failure, equipment jam, etc.). 1.2. Repair or correct the condition which caused the overcurrent condition. 1.3. Reset the circuit breaker or replace the set of fuses for the circuit. Must fix the cause of the Breaker or Fuse blowing before you reset or replace.

Identify and explain the different approach boundaries.

- Limited Approach boundary at 48" or the limit of the Flash Hazard Boundary when a Flash Hazard is present. - Limited: Minimum distance between unqualified individuals and potentially energized, exposed conductors. - Flash: Minimum distance at 48"" from potentially energized, exposed conductors that requires a Qualified person to wear flash hazard PPE. Varies based on the available fault current for the particular panel - Restricted: Minimum distance from exposed, potentially energized conductors in which a qualified individual must wear shock hazard PPE. Less than 50 V no restriction, 120V = 1 foot, 480V = 1 foot. - Prohibited; Minimum distance from potentially, energized exposed conductors under which energized work practices must be followed. No non-insulated tools are allowed past the Prohibited Approach Boundary. See Site Electrical Safe Practices, Laminated Cheat Sheet from Basic Electrical Training, or the Basic Electrical Training book.

Define the NEC requirements for working clearances and dedicated equipment space around electrical equipment.

30 inches wide or the width of the panel, 6 feet 6 inches of height, and 36" of clear space when 120V or 480V without a grounded surface(Insulated). 42" out from 480V to a grounded surface (bollard, wall, sheet metal, piece of equipment). 48" when the panel across may be open at the same time and has exposed 480V conductors. Dedicated Equipment space 6ft above the top the electrical panel, MCC, or PDP.

Explain the key components of 1910.331

331--Electrical safety work practices for both qualified persons (those who have training in avoiding the electrical hazards of working on or near exposed energized parts) and unqualified persons (those with little or no such training) working on, near, or with the following installations

Explain the key components of 1910.332

332--The training requirements contained in this section apply to employees who face a risk of electric shock that is not reduced to a safe level by the electrical installation requirements of 1910.303 through 1910.308.

Explain the key components of 1910.333

333--Safety-related work practices shall be employed to prevent electric shock or other injuries resulting from either direct or indirect electrical contacts, when work is performed near or on equipment or circuits which are or may be energized. The specific safety-related work practices shall be consistent with the nature and extent of the associated electrical hazards.

Explain the key components of 1910.334

334--Portable electric equipment. This paragraph applies to the use of cord and plug connected equipment, including flexible cord sets (extension cords).

Explain the key components of 1910.335

335--Use of protective equipment. Employees working in areas where there are potential electrical hazards shall be provided with, and shall use, electrical protective equipment that is appropriate for the specific parts of the body to be protected and for the work to be performed.

Demonstrate the proper procedure for inspecting and using insulated tools.

All insulated tools must be inspected for defects in the insulated areas of the tools. Most insulated tools have two-color insulation which will readily identify any area of the outer insulation which has been damaged to expose the inner insulation layer. These tools must be replaced when the insulation is damaged.

Explain the electrical safety incident reporting requirements for the site.

All shock incidents must be reported to your safety functional leader immediately and the site ESO within 24hours. Any trip of LV substation breakers or MV protective devices must be reported to the ESO in 24 hours. Any incidents where fuses or breakers have tripped or activated on a given circuit more than twice. Source: Electrical Key Element Audit questions.

Identify which individuals at a site are covered by OSHA 1910.331-335.

Everyone at the Lima site. The Code applies to both "Qualified" (those individuals who have been specifically trained to recognize and avoid electrical hazards - which means our level 1,2,3, & LVQ) and "Unqualified or untrained" personnel.

Low Voltage Qualification allows you to perform electrical tasks on equipment in what voltage range according to PCP 650?

Low Voltage Qualification: Up to 1KV

Demonstrate the ability to read and interpret the NFPA70E PPE Table 130.7.

NFPA Table 130.7 is the laminated PPE selection table provided at the end of the Basic Electrical Level 3 training. You must be able to use this table with the decision tree in order to select the appropriate PPE to be used when working with a piece of equipment which has not had a flash hazard analysis completed, or has not been labeled with a PPE Class.

Explain the function and operation of a safety ground cluster.

The safety ground clusters connect the three phases of a circuit to each other and to ground in order to provide a low resistance current path to ground for any energy source that could energize the circuit while people are working on it. The ground cluster is attached to the grounding bus or cable first. Any residual or accidental energy in each phase conductor is then drained to ground by contacting each phase with a lead of the ground cluster using a hot stick. Once all three phases have been drained using this procedure, the three unconnected ground cluster leads can be clamped, one at a time, to the phase conductors, one per phase. Only when all the grounding leads have been connected can the required flash hazard PPE be removed. In the event the circuit becomes energized after the ground cluster is applied, the ground cluster is intended to equalize the voltage across all three phases and provide the lowest resistance path to ground to force the upstream protection to activate and clear the fault without electrocuting the people protected by the ground cluster. Ground clusters which have experienced an event where the upstream protection has activated must be replaced regardless.

Explain what requirements need to be met to establish a panel as "Touch Safe."

"A touch safe panel is "Incapable of being inadvertently touched or approached nearer than the restricted approach boundary. If access to an energized part is a hole through an insulated guarding material with a diameter of ¼" or less, the energized part is not considered exposed and the installation shall be considered touch safe. A panel that is considered Touch Safe may be rendered not Touch Safe through the removal of guarding which exposes energized conductors. " Source: Electrical Safe Practices 24 volt ONLY panels are considered "Touch Safe" (ie, no powersupply with 120V in the panel or the installation has been approved as Touch Safe by the ESO). Electrical panels marked as "Touch Safe" may be accessed by non-qualified personnel, assuming the Touch Safe status of the panel has not been compromised (i.e. guards removed). Touch Safe panels shall be indicated by placement of a "Touch Safe" sticker on the panel door

Define "Energized Work"

"Energized Work is defined as the maintenance, adjustment, or repair of components or conductors that are electrically energized at 50V or more. Work on de-energized circuits within the prohibited approach boundary (1" at 480V) of other energized conductors is considered energized work.

Explain the factors that determine the severity of an electrical injury.

"Path of current flow, current level, and time. The path of the current, if it passes through the heart or nervous system, could cause more severe damage than if it passes through soft tissue & muscle. The current level determines the degree of damage by how much of the tissues are destroyed in combination with the duration of the heating of the tissue.

Explain the first aid response for dealing with a shock victim.

Call 5566. Disconnect the power source. If you cannot disconnect the power source - use wood, dry felt or other non-conductive material to remove the victim from the energized circuit. See Site Electrical Safe Practices, pg. 30.

Identify the classes of flash hazard PPE and explain how an individual would know what type of PPE to use when working in an energized panel.

Class -1: touch-safe panels. Normal work attire, safety glasses w/side shields Class 0: live 50V or more w/curable burn distance of less than 14"". Range of calculated incident energy - 0 - 2 cal/cm2. Long sleeve (100% cotton) normal work attire, rubber insulated gloves (500V) within restricted approach boundary. Insulated tools, safety glasses with side shields. Class 1: live 50V or more with a curable burn distance of 14""-18"". Range of calculated incident energy - 2 - 5 cal/cm2. Nomex IIIA shirt and denim pants or Nomex IIIA lab coat and denim pants. Rubber insulated gloves - voltage rated to match application, insulated tools, safety glasses w/side shields. Class 2: live 50V or more with a curable burn distance over 18"". Range of calculated incident energy - 5 - 10 cal/cm2. Endura Ultrasoft Coverall or Nomex shirt/pants w/Nomex lab coat. Rubber insulated gloves - voltage rated to match application, insulated tools (not for MV), safety glasses w/side shields, Class II face protection shield, ear protection when working on >1000V. Class 3: live 50V or more with a curable burn distance over 18"". Range of calculated incident energy - 10 - 32 cal/cm2. Normal cotton work attire and 30 cal/cm2 flash suit. Rubber insulated gloves - voltage rated to match application, insulated tools, safety glasses w/side shields, electric arc hood w/hard hat and flash rated face shield, hearing protection. Class 4: Live 50V or more with a curable burn distance >18"". Range of Calculated Incident Energy 32 - 50 cal/cm2. Normal work attire, Endura Ultrasoft Coverall and 30 cal/cm2 flash suit OR normal work attire and 100 cal/cm2 flash suit. Rubber insulated gloves - voltage rated to match application, insulated tools, safety glasses with side shields, electric arc hood with hard hat and flash rated face shield, hearing protection.

Demonstrate the proper procedure for inspecting LV gloves prior to use.

Gloves are to be removed from the protective carrying bag, visually inspected for any physical damage or contamination, then inflated and maintained in an inflated state to determine if there are any pinhole defects in the gloves. Gloves must pass all inspections before use after being stored in their protective carrying bag. Gloves are exchanged quarterly (Red to Black) and sent in to a test lab where they are tested are put thru tests to insure there are no holes in them and safe to work on electrical systems. If they fail the test they are disposed of and George H. replaces them with new ones.

Explain the site's requirements for electrical maintainance LO/TO, mechanical maintenance LO/TO, and operational LO/TO.

See LIMA PLANT ELECTRICAL SAFE WORK PRACTICES, page 9 - 2) Electrical Maintenance Lockout/Tagout

Identify the components of shock hazard PPE and explain how and where they are to be used.

Shock hazard PPE is comprised of the appropriate voltage rated glove protection and the use of insulated tools. This PPE is to be used any time an individual crosses the Restricted Approach Boundary as defined by the maximum voltage present in the equipment.

Locate a copy of the site's electrical safe practices.

Site Electrical Safe Practices are located on the L-Drive. \\Lm-fpna001\vol1\SHARED\Written Procedures Approved\HS&E\A. General Plant and Visitor\Safe Practices Level 3 Basic Electrical Training manual In the Site Safe Practices book in the HSE Offices Source: Gap Training, George, your area PC&IS Engineer

Conduct an electrical safety BOS.

Use the requirements from the Electrical Safe Practices to audit an electrical job looking for compliance with Flash Hazard PPE, Shock Hazard PPE, use of insulated tools, appropriate Limited Approach Boundary marking, use of correct tools & equipment, and appropriate LOTO (if applicable).

Explain the information that goes into a flash hazard boundary calculation.

Voltage Level, Available fault current, Upstream protection fault interrupting/clearing time. Voltage level and available fault current determine the amount of Arc energy available and the clearing time determines how long the fault can exist. Intensity and duration determine the total energy available to the Flash hazard. The boundary is set at the distance required to have the Cal/cm2 energy at a level that will only result in a 2nd degree burn. Source: Basic Electrical #3, ESO, Area PC&IS Engineer, Site Flash Hazard and Coordination Study.

Identify the situations in which non-qualified personnel may enter a Limited Approach Boundary.

When working under the direct supervision of a LVQ individual and they must be wearing the appropriate PPE. If an LVQ individual has verified the equipment is de-energized and the equipment has been locked out by the LVQ individual first, the non-qualified personnel may enter the Boundary. The unqualified individual must also lock out the equipment. Why? The qualified individual is responsible for the non-qualified individual because they are aware of the hazards of the energized equipment. This exception is in place to enable training of the non-qualified individual. When the equipment is locked out, the LVQ person is assuring the safety of the non-qualified individual by using their training and knowledge of the electrical hazards of the system.

Identify the people who may apply ground clusters and the situations which require the application of safety grounds.

a) Application of ground clusters may only be executed by MVQ individuals. b) Two MVQ individuals must be present for the application of ground clusters. One may be outside the flash hazard boundary. c) The following 13kV and 480V equipment must be properly grounded before work may begin on the equipment: i. Plant main isolation switches i.ii. 13kV Busses and isolation switches i.iii. Substation busses and breakers i.iv. Substation transformers (primary and secondary) i.v. Primary disconnects vi. MV MCC bus

Demonstrate the procedure for properly conducting an electrical maintenance lock-out.

a) Lockout and tagout is required when performing maintenance, adjustment, or repair on electrical equipment where injury is possible due to inadvertent energization of a power or control circuit. Maintenance, adjustment, or repair of energized electrical equipment may be performed under the "Energized Work" requirements set forth in section B(7) of this safe practice. b) Troubleshooting of power and control circuits, including the use of test equipment, is not considered energized work and does not require an "Energized Work Permit." While qualified individuals are performing troubleshooting work. c) Equipment must be stopped using normal operational means prior to operation of a disconnect. Individuals must not open or close disconnect switches while standing directly in front of them. d) All circuits, regardless of disconnect state, must be considered energized until the circuit is verified. The correct procedure for verification of circuit de-energization is: i. Using proper test equipment, verify circuit is energized. If the circuit could not be energized, verify operation of test equipment on a known live circuit. ii. Isolate circuit using appropriate switch. iii. Place lock and tag on switch mechanism. iv. Verify circuit is de-energized using the same test equipment used in the first step of this procedure. v. Verify operation of test equipment on a known live circuit.

Demonstrate or explain the appropriate response to a tripped LV substation breaker.

a) Operation of a substation breaker always requires the presence of two LVQ individuals. Operation of a MV switch requires the presence of two qualified individuals, one of which must be MVQ. a)b) In the event of a substation breaker operation, the plant PC&IS Leader or plant Electrical System Owner must be contacted. The breaker may not be re-closed until the source of the fault has been clearly determined and addressed. c) If the source of a substation breaker fault can not be readily identified, each load downstream of the breaker must be electrically isolated. The cables to each load must be checked using appropriate test equipment (Meggar). Only after each cable has been checked, may the main breaker be closed. Each load must then be brought online individually.


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