Electrical safety and quality assurance part A qn with answers PDF

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BM8076-ELECTRICAL SAFETY AND QUALITY ASSURANCETWO MARKS WITH ANSWERSUNIT-IELECTRICAL HAZARDSPART-A1. Define Hazard.It is defined as Event or situation with potential harm in terms of injury, damage to property, damage to workplace environment or combination of these are also known as Hazard.2. Defin...

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Subject Code / Name: BM8076-ELECTRICAL SAFETY AND QUALITY ASSURANCE

BM8076-ELECTRICAL SAFETY AND QUALITY ASSURANCE TWO MARKS WITH ANSWERS UNIT-I ELECTRICAL HAZARDS PART-A 1. Define Hazard. It is defined as Event or situation with potential harm in terms of injury, damage to property, damage to workplace environment or combination of these are also known as Hazard. 2. Define Electrical Hazard An electrical hazard can be defined as a serious workplace hazard that exposes workers to electrical injuries. 3. Define Electrical Safety Electrical safety is a system of organizational measures and technical means to prevent harmful and

dangerous

effects

on

workers

from electric

current, electric

arc, electromagnetic

field and static electricity. 4. Mention the common electrical hazards 

Improper Grounding



Exposed Electrical Parts



Inadequate Wiring



Damaged Insulation



Overloaded Circuits



Damaged Tools



Equipment Wet Conditions

5. What is mean by Electrocution? 

Electrocution results when a human is exposed to a lethal amount of electrical energy.



The word is derived from "electro" and "execution", but it is also used for accidental death

6. What is mean by burns and its types ? A burn is the most common shock related injury. Burns from electricity are one of three types: Electrical Burns Arc/Flash Burns Thermal Contact Burns

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Subject Code / Name: BM8076-ELECTRICAL SAFETY AND QUALITY ASSURANCE

7. Define Shock 

Electrical shock is defined as a reflex response to the passage of electric current through the body.



Shock results when the body becomes part of the electrical circuit

8. State the factors influencing severity. The severity of electric shock or the amount of current which flows on the body depends on 

Frequency of supply



Level of voltage



State of the point of contact with the body



Duration of exposure



Resistance of the body

9. Mention the dangers in low voltage system. 

Secondary shock hazards



Arc in a low-voltage system has the same- potential for igniting explosive materials



Short circuit

10. Define Current Path 

From one finger to another finger the effect will be concentrated between two points



From one hand to another hand, current will pass through the heart



From left hand to right foot, current will pass through vital organs

11. What is mean by duration of exposure? For an electric shock to have an effect a person needs to be in contact with the circuit for sufficient time. The longer the person is in contact with the current the more harm it may cause. It is also known as duration of exposure. 12. State main hazard of static electricity. The main hazard of static electricity is the creation of sparks in an explosive or flammable atmosphere. These sparks can set off an explosion or fire. The danger is greatest when flammable liquids are being poured or transferred. 13. Mention the four conditions in hazard of static electricity.

ESQA



For static electricity to be a hazard, four conditions must be met:



There must be a means for a static charge to develop.



Enough energy must build up to cause ignition.



There must be a discharge of this energy (a spark). DSEC/BME/QB/IV YR/ESQA

Subject Code / Name: BM8076-ELECTRICAL SAFETY AND QUALITY ASSURANCE



The spark must occur in an ignitable vapor or dust mixture

14. Mention the engineering control in electrical hazards. 

Redesign a process to place a barrier between the person and the hazard



Remove the hazard from the person, such as machinery guarding, proximity guarding, extraction systems



Removing the operator to a remote location away from the hazard.

15. Mention the administrative control in electrical hazards.



Adopting standard operating procedures



Safe work practices



Providing appropriate training, instruction information to reduce the potential for harm and/or adverse health effects to person(s).



Isolation and permit to work procedures are examples of administrative controls.

16. What is mean by Energy leakage

In electronics, leakage is the gradual transfer of electrical energy across a boundary normally viewed as insulating, such as the spontaneous discharge of a charged capacitor, magnetic coupling of a transformer with other components, or flow of current across a transistor in the "off" state or a reverse-polarized diode 17. Define thermal insulation Thermal insulation usually refers to the use of appropriate insulation materials and design adaptations for buildings to slow the transfer of heat through the enclosure to reduce heat loss and gain.[1] The transfer of heat is caused by the temperature difference between indoors and outdoors. [1] Heat may be transferred either by conduction, convection, or radiation 18. What is mean by flame? A

flame

is

a

mixture

of

reacting

gases

and

solids

emitting

visible, infrared,

and

sometimes ultraviolet light, the frequency spectrum of which depends on the chemical composition of the burning material and intermediate reaction products. In many cases, such as the burning of organic matter, for example wood, or the incomplete combustion of gas, incandescent solid particles called soot produce the familiar red-orange glow of "fire".

19. What is mean by fire ? Fire is the rapid oxidation of a material in the exothermic chemical process of combustion, releasing heat, light, and various reaction products. Fire is hot because the conversion of the weak double bond in molecular oxygen, O2, to the stronger bonds in the combustion

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Subject Code / Name: BM8076-ELECTRICAL SAFETY AND QUALITY ASSURANCE

products carbon dioxide and water releases energy (418 kJ per 32 g of O2); the bond energies of the fuel play only a minor role here.

20. What is mean by inrush-current? Inrush current, input surge current, or switch-on surge is the maximal instantaneous input current drawn by an electrical device when first turned on. Alternating-current electric motors and transformers may draw several times their normal full-load current when first energized, for a few cycles of the input waveform. UNIT-II STANDARDS AND REQUIREMENTS PART-A 1. What is the main purpose of National electrical safety code? The purpose of these rules is the practical safeguarding of persons during the instaIlation, operation, or maintenance of electric supply and communication lines and associated equipment. These rules contain the basic provisions that are considered necessary for the safety of employees and the public under the specified conditions. This code is not intended as a design specification or as an instruction manual. 2. Is the National Electrical Code a law? National Electrical Code (NEC) ... While the NEC is not itself a U.S. law, NEC use is commonly mandated by state or local law, as well as in many jurisdictions outside of the United States. The NEC codifies the requirements for safe electrical installations into a single, standardized source 3. How Can OSHA Help Me? OSHA can provide extensive help through a variety of programs, including assistance about safety and health programs, state plans, workplace consultations, voluntary protection programs, strategic partnerships, training and education, and more. 4. How does safety and health program management assistance help employers and employees? Working in a safe and healthful environment can stimulate innovation and creativity and result in increased performance and higher productivity.

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Subject Code / Name: BM8076-ELECTRICAL SAFETY AND QUALITY ASSURANCE

The guidelines identify four general elements that are critical to the development of a successful safety and health management system: i. management leadership and employee involvement, ii. worksite analysis, iii. hazard prevention and control, and safety and health training.

5. Can OSHA assure privacy to an employer who asks for consultation assistance?

OSHA provides consultation assistance to the employer with the assurance that his or her name and firm and any information about the workplace will not be routinely reported to OSHA enforcement staff. 6. Can an employer be cited for violations after receiving consultation assistance?

If an employer fails to eliminate or control a serious hazard within the agreed-upon time frame, the consultation project manager must refer the situation to the OSHA enforcement office for appropriate action. This is a rare occurrence, however, because employers request the service for the expressed purpose of identifying and fixing hazards in their workplaces. 7. Does

OSHA

provide

any

incentives

for

seeking

consultation

assistance?

Yes. Under the consultation program, certain exemplary employers may request participation in OSHA's Safety and Health Achievement Recognition Program (SHARP). Eligibility for participation in SHARP includes, but is not limited to, receiving a full-service, comprehensive consultation visit, correcting all identified hazards, and developing an effective safety and health management system. 8. Does OSHA give money to organizations for training and education?

OSHA awards grants through its Susan Harwood Training Grant Program to nonprofit organizations to provide safety and health training and education to employers and workers in the workplace. The grants focus on programs that will educate workers and employers in small business (fewer than 250 employees), training workers and employers about new OSHA standards or about high-risk activities or hazards. Grants are awarded for 1 year and ESQA

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Subject Code / Name: BM8076-ELECTRICAL SAFETY AND QUALITY ASSURANCE

may be renewed for an additional 12 months depending on whether the grantee has performed satisfactorily. 9. What is OSHA's Strategic Partnership Program (OSPP)?

OSHA Strategic Partnerships are alliances among labor, management, and government to foster improvements in workplace safety and health. These partnerships are voluntary, cooperative relationships between OSHA, employers, employee representatives, and others such as trade unions, trade and professional associations, universities, and other government agencies. OSPPs are the newest member of OSHA's family of cooperative programs.

10. What is mean by Clear space When normally enclosed energized parts are exposed for inspection or servicing, the working space, if in a passageway or general open space, shall be guarded. This is known as clear space. 11. What is a good safety message? Getting the Safety Message Across Here are some examples of safety rhymes: "Falling objects can be brutal, so wear your hard hat to protect your noodle." "A spill or a slip could mean a hospital trip." "Working in a safe way means you will live to see another day." 12. What are the four basic principles of safety management?  Safety Policy.  Safety Risk Management.  Safety Assurance.  Safety Promotion. 13. What are the four elements of risk assessment? There are four parts to any good risk assessment and they are Asset identification, Risk Analysis, Risk likelihood & impact, and Cost of Solutions. 14. What are safety principles? A basic principle of safety can be illustrated by the accident triangle. This safety principle reasons that the best way to avoid death, injury and property loss is to stay out of the Near Miss zone. ... For example, consider the hazard of smoking in bed. 15. Why is safety important in design? Good work design, or safety in design, considers hazards and risks as early as possible in the planning and design process. It aims to eliminate or minimise the possibility of workplace injury or illness throughout the life of the product or process. ... The principles can be applied to all design including: facilities ESQA

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Subject Code / Name: BM8076-ELECTRICAL SAFETY AND QUALITY ASSURANCE

16. What is the safety design review process? In the Safety Design Review process, the goal is to avoid bringing hazards into the workplace. The Safety Design Review is a proactive approach that anticipates hazards and potential hazards to avoid bringing them into the workplace with this new equipment or process or facility update. 17. What is an example of a benchmark? For example, benchmarks could be used to compare processes in one retail store with those in another store in the same chain. External benchmarking, sometimes described as competitive benchmarking, compares business performance against other companies 18. Is standards for electrical safety? OSHA's electrical standards are based on the National Fire Protection Association Standards NFPA 70, National Electric Code, and NFPA 70E, Electrical Safety Requirements for Employee Workplaces. OSHA also has electrical safety standards for the construction industry, in 29 CFR 1926, Subpart K

19. What is a hazard example? A hazard is something that can cause harm, e.g. electricity, chemicals, working up a ladder, noise, a keyboard, a bully at work, stress, etc. ... For example, working alone away from your office can be a hazard. The risk of personal danger may be high. Electric cabling is a hazard 20. What is mean by National electrical safety code? The National Electrical Safety Code (NESC) or ANSI Standard C2 is a United States standard of the safe installation, operation, and maintenance of electric power and communication utility systems including power substations, power and communication overhead lines, and power and communication underground lines. UNIT-III ELECTRICAL PROTECTION AND MAINTENANCE PART-A

1. What is the best way to protect yourself against electrical hazards? Most electrical accidents result from one of the following three factors:   

unsafe equipment or installation, unsafe environment, or unsafe work practices.

Some ways to prevent these accidents are through the use of insulation, guarding, grounding, electrical protective devices, and safe work practices.

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Subject Code / Name: BM8076-ELECTRICAL SAFETY AND QUALITY ASSURANCE

2. What protection does insulation provide? Insulators such as glass, mica, rubber, or plastic used to coat metals and other conductors help stop or reduce the flow of electrical current. This helps prevent shock, fires, and short circuits. To be effective, the insulation must be suitable for the voltage used and conditions such as temperature and other environmental factors like moisture, oil, gasoline, corrosive fumes, or other substances that could cause the insulator to fail. 3. How do you identify different types of insulation? Insulation on conductors is often color coded. Insulated equipment grounding conductors usually are either solid green or green with yellow stripes. Insulation covering grounded conductors is generally white or gray. Ungrounded conductors, or " hot wires," often are black or red, although they may be any color other than green, white, or gray. Before connecting electrical equipment to a power source, it's a good idea to check the insulation for any exposed wires for possible defects. Insulation covering flexible cords such as extension cords is particularly vulnerable to damage.

4. What is guarding and what protection does it offer? Guarding involves locating or enclosing electric equipment to make sure people don't accidentally come into contact with its live parts. Effective guarding requires equipment with exposed parts operating at 50 volts or more to be placed where it is accessible only to authorized people qualified to work with it. Recommended locations are a room, vault, or similar enclosure; a balcony, gallery, or elevated platform; or a site elevated 8 feet (2.44 meters) or more above the floor. Sturdy, permanent screens also can serve as effective guards. 5. What is grounding and what protection does it offer? " Grounding" a tool or electrical system means intentionally creating a low-resistance path that connects to the earth. This prevents the buildup of voltages that could cause an electrical accident. Grounding is normally a secondary protective measure to protect against electric shock. It does not guarantee that you won't get a shock or be injured or killed by an electrical current. It will, however, substantially reduce the risk, especially when used in combination with other safety measures discussed in this booklet. 6. What are circuit protection devices and how do they work? Circuit protection devices limit or stop the flow of current automatically in the event of a ground fault, overload, or short circuit in the wiring system. Well-known examples of these devices are fuses, circuit breakers, ground-fault circuit interrupters, and arc-fault circuit interrupters. Fuses and circuit breakers open or break the circuit automatically when too much current flows through them. When that happens, fuses melt and circuit breakers trip the circuit open. Fuses and ESQA

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Subject Code / Name: BM8076-ELECTRICAL SAFETY AND QUALITY ASSURANCE

circuit breakers are designed to protect conductors and equipment. They prevent wires and other components from overheating and open the circuit when there is a risk of a ground fault. 7. What work practices help protect you against electrical hazards? Electrical accidents are largely preventable through safe work practices. Examples of these practices include the following: deenergizing electric equipment before inspection or repair, keeping electric tools properly maintained, exercising caution when working near energized lines, and using appropriate protective equipment. 8. How can you protect yourself against metal parts that become energized? A break in an electric tool's or machine's insulation can cause its metal parts to become " hot" or energized, meaning that they conduct electricity. Touching these energized parts can result in an electrical shock, burn, or electrocution. The best way to protect yourself when using electrical tools or machines is to establish a low-resistance path from the device's metallic case to the ground. This requires an equipment grounding conductor, a low-resistance wire that directs unwanted current directly to the ground.

9. How can you prevent an accidental or unexpected equipment startup? Proper lockout/tagout procedures protect you from the dangers of the accidental or unexpected startup of electrical equipment and are required for general industry by OSHA Standard 1910.333, Selection and Use of Work Practices. Requirements for construction applications are in 29 CFR 1926.417, Lockout and Tagging of Circuits. These procedures ensure that electrical equipment is deenergized before it is repaired or inspected and ...