Electrical safety in the workplace - An toàn điện tại nơi làm việc

“Electrical Safety in the Workplace” This material was produced under Grant #SH-16609-07-60-F-26 from the Occupational Safety and Health Administration, U.S Department of Labor It does not necessarily reflect the views or policies of the U.S Department of Labor, nor does mention of trade names, commercial products, or organizations imply endorsement by the U.S Government September 2008 “Electrical Safety in the Workplace” Course Goal – The aim of this program is to provide comprehensive on-site training to high-risk workers (i.e skilled trades and maintenance workers) and management on the requirements of Sub Part S, and the prevention of serious injuries from electrical hazards at their worksites Participants will develop understanding of the requirements of OSHA Sub Part “S” and NFPA, 70E and will be able to identify and reduce or eliminate electrical safety hazards in their workplace Electrical Safe Work Practices including electrical safety principles, guidelines for qualification of personnel, job planning requirements and Management and Personal Responsibility will be covered Section Content Introduction to Electrical Safety Identifying the Hazards OSHA Requirements Safety Related Work Practices Objective Participants will be able to: • Explain the issues (statistics) associated with poor electrical safety in the workplace • Recall key electrical terms which are essential to understanding and meeting the requirements of key electrical safety standards; i.e OSHA 29 CFR 1910.331-.335, NFPA 70E, NEC (NFPA 70) • Define and differentiate between qualified and unqualified persons under OSHA Sub Part S and the training requirements for each • Describe the intent of an Electrical Safety Program and list the essential elements of an effective program • Use a “Status Check” survey to assess the facility’s electrical safety program and where necessary develop strategies for improvement Participants will be able to: • List types of electrical hazards to personnel and describe the nature of the hazards related to: o Electric shocks, arcs and blasts o Fault current and potential difference o Electrical safety in industrial plants • List the characteristics of an arc flash hazard • List the characteristics of an arc blast hazard • Explain how other injury hazards are related to shock, flash, and blast Participants will be able to: • Identify requirements specified in OSHA 29 CFR 1910.301-.308 and NFPA 70E2004 Chapter and describe similarities and differences in OSHA and 70E • Explain how NFPA 70E is used in OSHA compliance and enforcement • Determine training for workers in accordance with OSHA Sub Part S requirements • Recall Safe Installation Practices including: o Guarding o Identification o Flexible cords and cables o System grounding o Location of overcurrent protection devices o Workspace clearance requirements • Assess an electrical installation for compliance with OSHA regulations • Explain the reasons for doing a site assessment to determine arc flash hazard potential for equipment and electrical enclosure Participants will be able to: • Identify requirements for electrical safe work practices specified in OSHA 29 CFR 1910.331-.335 and NFPA 70E Chapter • Define an “Electrically Safe Work Condition” and list specific steps to be taken to ensure an electrically safe work condition • Explain how the creation of an electrically safe work condition can involve hazards “Electrical Safety in the Workplace” and the methods to protect against them • Describe the facility’s lockout/tagout (LO/TO) procedure including requirements and activities in the procedure and identify the persons responsible for each activity • Determine the LO/TO procedure applicable to a given facility, operation, equipment or activity • Describe other safety related work practices to protect from electrical hazards including: o Selection and use of work practices o De-energized work practices o Energized work practices o Approach boundaries and approach distances o Requirements for use of test instruments and equipment o Requirements for insulated tools o Other equipment such as ladders, barricades, signs Working On or Near Live Parts Participants will be able to: • Identify persons who may be exposed to a source of electrical energy directly or indirectly • List the conditions under which “hot work” is allowed • Describe the purposes of an energized electrical work permit • Recall three types of approach boundaries and define the dimensions of each approach boundary, given all necessary information • Describe the essential parts of a Flash Hazard Analysis and list the data required analysis • List the information, including Hazard Risk Category, provided to a worker by a Flash Hazard Analysis and describe its use Personal Protective Equipment (PPE) Participants will be able to: • List the basic types of personal protective equipment (PPE) for tasks involving electrical hazards • Describe how each type protects against hazards and identify the limitations of PPE • Explain the need for flame resistant (FR) clothing and layering of clothing for protection and list clothing prohibited where electrical hazards are present • Select PPE for a given Hazard Risk Category including gloves, eye, head, face protection and (FR) clothing • Describe the requirements for use, care, maintenance and storage of PPE Action Planning and Course Wrap-up Participants will be able to: • Outline an Action Plan to achieve compliance with OSHA Subpart S and NFPA 70E • Provide assistance to help achieve workplace goals of OSHA Subpart S and NFPA 70E compliance “Electrical Safety in the Workplace” AGENDA Section Content Page # 1* Introduction to Electrical Safety 2* Identifying the Hazards 13 3* OSHA Requirements 28 Safety Related Work Practices 33 Working On or Near Live Parts 35 Personal Protective Equipment 40 Action Planning and Course Wrap-up 62 * Denotes Electrical Hazard Awareness training sections “Electrical Safety in the Workplace” Introductions Individual Introductions: ♦ Your name, worksite, local union, job title and/or Union title Introductions: How long have you been doing electrical repairs or troubleshooting? What electrical responsibilities you know are within your training? 1) 2) What electrical responsibilities you know are outside your training? 1) 2) What type of Personal Protective Equipment (PPE) is available to you when working on or near live electrical equipment? _ Answer the following throughout the session -5 What action does your facility need to take to comply with the revised Electrical Standards? Sticky notes are at the tables As we cover ideas, you’ll think, “Our facility needs to (fill in the blank) to take care of this!” When you do, write that action on a post-it note, along with the page number that sparked it Pile the notes in front you They will be used in the wrap-up planning exercise “Electrical Safety in the Workplace” A Checklist to Clarify Status Column Do these items describe your facility? Answer YES, NO, or SOMEWHAT ITEM Each sentence starts with “Does Your Facility… ” …work on 50V or more? …have all breakers and switches marked for what it goes to? …provide Lockout/Tagout (LOTO) training for everyone? .provide GFI protection for extension cords and electric portable tools? …provide Flame Retardant (FR) clothing to “qualified” personnel? .stress LOTO before doing any service or maintenance on electrical components? …inspect electrical cords on portable tools and extension cords prior to each use? …have a procedure for taking damaged cords out of service for repairs prior to use? …have all panels / Electrical Cabinets marked for voltage? 10 .provide “Electrical Hazard Awareness Training” for everyone? 11 .reset breakers with “qualified” personnel? 12 .have an electrical room or vault? 13 .is the room secured to prevent “unqualified” personnel from entering? 14 .use dielectric tested gloves when working on/near live electrical parts? 15 …use insulated tools when working on/near live electrical parts? 16 .do Preventitive Maintenance on circuit breakers and switches at least annually? 17 .have 40 cal/cm2 suits available? 18 .have buss plugs that are changed by personnel? 19 .work on live electrical equipment to trouble shoot or because it can’t be shut down? 20 .have all the incident energy calculated and Arc Flash Boundaries set for all service connections of 50V or more? 21 …are the boundaries posted on panels/disconnects? 22 .use a “Hot Electrical Work Permit” system? 23 … install new equipment or rebuild older equipment? 24 .keep all electrical cabinets and electrical disconnects clear (36”)? 25 … use approved electrical test devices? 26 .have someone trained in CPR-1st Aid and AED? 27 …inspect PPE prior to each use? Circle the top items that your facility most needs to improve Next, compare your responses to those of others in your group: What are the common concerns? Where are the differences? What work has to be done? “Electrical Safety in the Workplace” What’s wrong here? What’s the problem? _ Can this cabinet be turned back on and create a hazard? How many hazards/violations are there in this picture? “Electrical Safety in the Workplace” A Little History of Electricity 600BC: Static electricity Thales, a Greek, found that when amber was rubbed with silk it attracted feathers and other light objects He had discovered static electricity The Greek word for amber is elektron', from which we get electricity' and electronics' 1600: William Gilbert invented the term electricity William Gilbert, scientist and physician to Queen Elizabeth I, coined the term electricity He was the first person to describe the earth's magnetic field and to realize that there is a relationship between magnetism and electricity 1752: Franklin proved that lightning is a form of electricity Benjamin Franklin, famous U.S politician, flew a kite with a metal tip into a thunderstorm to prove that lightning is a form of electricity 1820: Hans Christian Oersted discovered magnetic fields caused by electricity Hans Christian Oersted of Denmark found that when electricity flows through a wire, it produces a magnetic field that affects the needle of a nearby compass 1821: Michael Faraday's discovery that led to the invention of electric motors Michael Faraday discovered that when a magnet is moved inside a coil of copper wire, a tiny electric current flows through the wire This discovery later led to the invention of electric motors 1826: André Ampère explained the electro-dynamic theory André Ampère published his theories about electricity and magnetism He was the first person to explain the electro-dynamic theory The unit of electric current was named after Ampère 1827: Georg Ohm published his complete mathematical theory of electricity German college teacher Georg Ohm published his complete mathematical theory of electricity The unit of electrical resistance was later named after him 1831: The First Telegraph Machine Charles Wheatstone and William Fothergill Cooke created the first telegraph machine 1838: Samuel Morse invented Morse Code At an exhibition in NewYork, Samuel Morse demonstrated sending 10 words a minute by his new telegraph machine He used a system of dots and dashes, which later became standard throughout the world, known as Morse code 1870s: Thomas Edison built a DC electric generator Thomas Edison built a DC (direct current) electric generator in America He later provided all of New York's electricity 1876: Alexander Graham Bell invented the telephone Alexander Graham Bell, inventor of the telephone, used electricity to transmit speech for the first time “Electrical Safety in the Workplace” 1878: Joseph Swan demonstrated the first Electric Light Thomas Edison demonstrated the first electric light with a carbon filament lamp 1879: First fatal accident due to electric shock 1800’s: Nicola Tesla devised the AC (Alternating Current) system for electrical transmission that is used in homes, businesses and industry today He also invented the motors that run on AC and designed the world’s first Hydroelectric Plant (in Niagara Falls, NY) 1895: The first electric hand drill The first electric hand drill became available, invented by Wilhelm Fein 1918-19: Washing machines and refrigerators Electric washing machines and refrigerators first became available 1926: First National Grid was introduced Electricity Supply Act - the first National Grid was introduced 1930-40s: Electrical household appliances introduced Mains powered radios, vacuum cleaners, irons and refrigerators were becoming part of every household 1936: John Logie Baird pioneered the television 1752 “Electrical Safety in the Workplace” What Is Electricity? Electricity is everywhere in our lives Electricity lights up our homes, cooks our food, powers our computers, television sets, and other electronic devices Electricity (DC Current) from batteries starts our cars and makes our flashlights shine in the dark But what is electricity? Where does it come from? How does it work? What are the hazards? Before we understand all that, we need to know a little bit about atoms and their structure All matter is made up of atoms, and atoms are made up of smaller particles The three main particles making up an atom are the proton, the neutron and the electron Electrons spin around the center, or nucleus The nucleus is made up of neutrons and protons Electrons contain a negative charge, protons a positive charge Neutrons are neutral they have neither a positive nor a negative charge Each atom has a specific number of electrons, protons and neutrons But no matter how many particles an atom has, the number of electrons usually needs to be the same as the number of protons If the numbers are the same, the atom is called balanced, and it is very stable So, if an atom had six protons, it should also have six electrons The element with six protons and six electrons is called carbon Carbon is found in abundance in the sun, stars, comets, atmospheres of most planets, and the food we eat Coal is made of carbon; so are diamonds Some kinds of atoms have loosely attached electrons An atom that loses electrons has more protons than electrons and is positively charged An atom that gains electrons has more negative particles and is negatively charged A "charged" atom is called an "ion." Electrons can be made to move from one atom to another When those electrons move between the atoms, a current of electricity is created The electrons move from one atom to another in a "flow." One electron is attached and another electron is lost Since all atoms want to be balanced, the atom that has been "unbalanced" will look for a free electron to fill the place of the missing one We say that this unbalanced atom has a "positive charge" (+) because it has too many protons Since it got kicked off, the free electron moves around waiting for an unbalanced atom to give it a home The free electron charge is negative, and has no proton to balance it out, so we say that it has a "negative charge" (-) 10 “Electrical Safety in the Workplace” 49 “Electrical Safety in the Workplace” 1910.137 Electrical Protective Devices (Excerpt) Table I-6 - Rubber Insulating Equipment Test Intervals Type of equipment | When to test _| | Rubber insulating line hose| Upon indication that insulating value | is suspect Rubber insulating covers | Upon indication that insulating value | is suspect Rubber insulating blankets | Before first issue and every 12 months | thereafter(1) Rubber insulating gloves | Before first issue and every months | thereafter(1) Rubber insulating sleeves | Before first issue and every 12 months | thereafter(1) _ _ Footnote(1) If the insulating equipment has been electrically tested but not issued for service, it may not be placed into service unless it has been electrically tested within the previous 12 months 50 “Electrical Safety in the Workplace” The Hierarchy of Health & Safety Controls Research indicates that fixing the workplace approach is actually more effective and less expensive in the long run One reason is that human behavior can never be completely regulated and controlled, so solutions based on compliance with procedures will always lead to mishaps Control of Hazardous Energy (LOTO) is much more capable of guaranteeing safety and health The UAW’s and OSHA’s analysis of control effectiveness is captured in the graph below MOST EFFECTIVE ↓ Elimination or Substitution Engineering Controls ↓ Warnings ↓ Training & Procedures LEAST EFFECTIVE Personal Protective Equipment • • • • substitute with less hazardous material change process to eliminate noise perform task at ground level automated material handling • • • • • • • • • • • • • • • • ventilation systems machine guarding Electrical enclosures Current limiting circuit breakers/fuses interlocks lift tables, conveyors, balancers odor in natural gas signs Barricades horns labels Safe job procedures Safety equipment inspections Hazard Communications Training Lock-out Confined Space Entry, etc… • • • • • • safety glasses ear plugs Flame Retardant Clothing face shields safety harnesses and lanyards Gloves Does your group agree about where to focus in the hierarchy? NO YES 51 “Electrical Safety in the Workplace” What Are Your Goals & Concerns? I What goals you want to achieve? _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 52 “Electrical Safety in the Workplace” Exploring Common Ground 1st: In the small groups, prioritize the goals you have identified in order of importance, ranking them by the total number of goals each group listed nd : Each group reports out its goals, one at a time, without identifying their priority ranking 3rd: The entire group discusses the following questions: How much common ground groups have in their goals? What surprised you in the other group’s list that you now realize is important? Do the common goals appear to be a full agenda? What goals are different? Why are they important to the group that presented them? 4th: Each small group will report out how it has prioritized goals 5th: The large group discusses the following questions: What similarities and differences are there in the group’s priorities? What difficulties might these differences cause? 1) _ 2) _ 3) _ 4) _ 6th: Each group reports out its concerns, one at a time, using a round robin as above 7th: Engage the full group in discussing the following questions What common concerns does the group have? 53 “Electrical Safety in the Workplace” Building an Agenda Common Ground – Goals for Worksite _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Note: Items on page 41 will need to be incorporated in your goals if not completed 54 Priority # # # # # # # # “Electrical Safety in the Workplace” Identify and Investigate Electrical Hazards • Conduct electrical inspections and walk-arounds Has this been done? ο YES If so, by whom? ο NO If not, to whom will this be assigned? • Gather information from workers in meetings, through surveys, suggestion programs, task forces on potential electrical hazards Has this been done? ο YES If so, by whom? _ ο NO If not, to whom will this be assigned? • Investigate equipment electrical hazards Has this been done? ο YES If so, by whom? _ ο NO If not, to whom will this be assigned? • Audit electrical operating procedures to identify hazards or concerns in work processes Has this been done? ο YES If so, by whom? ο NO If not, to whom will this be assigned? _ • Provide Education and Training a For Skilled Trades b For Supervision c For Workforce 55 “Electrical Safety in the Workplace” Preparing for an Inspection Prior to the inspection, review OSHA Sub Part “S” and NFPA 70E requirements and suggestions, what complaints, near misses and problems that have been reported or are apparent from records, such as: ¾ Workers’ questions, concerns, suggestions ¾ First aid/accident logs ¾ OSHA 300 Logs and 301 reports ¾ Electrical Safe Work Practices for facility ¾ Previous Year’s Lock-Out Plan ¾ Near miss reports Plan for the inspection by pursuing the following questions: 1) What are people doing in the area to be inspected? Review these: a) Site map and building plans b) Process flow charts c) Single line electrical drawings d) Narrative description of operations e) Written operating procedures 2) What previous assessments were made? Don’t duplicate work!! Review: a) Reports of previous inspections 3) What is the right way to an electrical assessment? Don’t reinvent the wheel! Review: a) OSHA (available on-line), NFPA, NEC, ANSI, ASHRAE standards (available for purchase) b) Electrical contractors reports, if they provide services to your worksite c) Others references Small Group Analysis of Inspection Checklists 1) What would you want to make sure you include in an Electrical checklist for your worksite? 56 “Electrical Safety in the Workplace” 2) What would you want to avoid in creating a checklist for your site? 3) What topics are important to your site that aren’t addressed – or are underaddressed by these checklists? What would your checklist include for these topics? 57 “Electrical Safety in the Workplace” Electrical Compliance Checklist (OSHA Small Business Publication #2209-02R 2005) Do you require compliance with OSHA standards for all contract electrical work? Yes / No / Don’t Know or Incomplete Are all employees required to report any obvious hazard to life or property in connection with electrical equipment or lines as soon as possible? Yes / No / Don’t Know or Incomplete Are employees instructed to make preliminary inspections and/or appropriate tests to determine conditions before starting work on electrical equipment or lines? Yes / No / Don’t Know or Incomplete When electrical equipment or lines are to be serviced, maintained, or adjusted, are necessary switches opened, locked out or tagged, whenever possible? Yes / No / Don’t Know or Incomplete Are portable electrical tools and equipment grounded or of the double insulated type? Yes / No / Don’t Know or Incomplete Are electrical appliances such as vacuum cleaners, polishers, vending machines, etc., grounded? Yes / No / Don’t Know or Incomplete Do extension cords have a grounding conductor? Yes / No / Don’t Know or Incomplete Are multiple plug adaptors prohibited? Yes / No / Don’t Know or Incomplete Are ground-fault circuit interrupters installed on each temporary 15 or 20 ampere, 120 volt alternating current (AC) circuit at locations where construction, demolition, modifications, alterations, or excavations are being performed? Yes / No / Don’t Know or Incomplete 10 Are all temporary circuits protected by suitable disconnecting switches or plug connectors at the junction with permanent wiring? Yes / No / Don’t Know or Incomplete 11 Do you have electrical installations in hazardous dust or vapor areas? If so, they meet the National Electrical Code (NEC) for hazardous locations? Yes / No / Don’t Know or Incomplete 12 Are exposed wiring and cords with frayed or deteriorated insulation repaired or replaced promptly? Yes / No / Don’t Know or Incomplete 13 Are flexible cords and cables free of splices or taps? Yes / No / Don’t Know or Incomplete 14 Are clamps or other securing means provided on flexible cords or Yes / No / Don’t Know cables at plugs, receptacles, tools, equipment, etc., and is the or Incomplete cord jacket securely held in place? 15 Are all cord, cable and raceway connections intact and secure? Yes / No / Don’t Know or Incomplete 16 In wet or damp locations, are electrical tools and equipment appropriate for the use or location or otherwise protected? Yes / No / Don’t Know or Incomplete 58 “Electrical Safety in the Workplace” 17 Is the location of electrical power lines and cables (overhead, underground, under floor, other side of walls, etc.) determined before digging, drilling, or similar work is begun? Yes / No / Don’t Know or Incomplete 18 Are metal measuring tapes, ropes, hand-lines or similar devices Yes / No / Don’t Know with metallic thread woven into the fabric prohibited where they or Incomplete could come in contact with energized parts of equipment or circuit conductors? 19 Is the use of metal ladders prohibited where the ladder or the person using the ladder could come in contact with energized parts of equipment, fixtures, or circuit conductors? Yes / No / Don’t Know or Incomplete 20 Are all disconnecting switches and circuit breakers labeled to indicate their use or equipment served? Yes / No / Don’t Know or Incomplete 21 Are disconnecting means always opened before fuses are replaced? Yes / No / Don’t Know or Incomplete 22 Do all interior wiring systems include provisions for grounding metal parts of electrical raceways, equipment and enclosures? Yes / No / Don’t Know or Incomplete 23 Are all electrical raceways and enclosures securely fastened in place? Yes / No / Don’t Know or Incomplete 24 Are all energized parts of electrical circuits and equipment guarded against accidental contact by approved cabinets or enclosures? Yes / No / Don’t Know or Incomplete 25 Is sufficient access and working space provided and maintained around all electrical equipment to permit ready and safe operations and maintenance? Yes / No / Don’t Know or Incomplete 26 Are all unused openings (including conduit knockouts) in electrical enclosures and fittings closed with appropriate covers, plugs, or plates? Yes / No / Don’t Know or Incomplete 27 Are electrical enclosures such as switches, receptacles, junction boxes, etc., provided with tight-fitting covers or plates? Yes / No / Don’t Know or Incomplete 28 Are disconnecting switches for electrical motors in excess of two horsepower able to open the circuit when the motor is stalled without exploding? (Switches must be horsepower rated equal to or in excess of the motor rating.) Yes / No / Don’t Know or Incomplete 29 Is low voltage protection provided in the control device of motors driving machines or equipment that could cause injury from inadvertent starting? Yes / No / Don’t Know or Incomplete 30 Is each motor disconnecting switch or circuit breaker located within sight of the motor control device? Yes / No / Don’t Know or Incomplete 31 Is each motor located within sight of its controller or is the controller disconnecting means able to be locked open or is a separate disconnecting means installed in the circuit within sight of the motor? Yes / No / Don’t Know or Incomplete 32 Is the controller for each motor that exceeds two horsepower Yes / No / Don’t Know 59 “Electrical Safety in the Workplace” rated equal to or above the rating of the motor it serves? or Incomplete 33 Are employees who regularly work on or around energized electrical equipment or lines instructed in cardiopulmonary resuscitation (CPR)? Yes / No / Don’t Know or Incomplete 34 Are employees prohibited from working alone on energized lines or equipment over 600 volts? Yes / No / Don’t Know or Incomplete LOCKOUT/TAGOUT PROCEDURES Checklist □ Is all machinery or equipment capable of movement required to be de-energized or disengaged and blocked or locked out during cleaning, servicing, adjusting, or setting up operations? □ If the power disconnect for equipment does not also disconnect the electrical control circuit, are the appropriate electrical enclosures identified and is a means provided to ensure that the control circuit can also be disconnected and locked out? □ Is the locking out of control circuits instead of locking out main power disconnects prohibited? □ Are all equipment control valve handles provided with a means for locking out? □ Does the lockout procedure require that stored energy (mechanical, hydraulic, air, etc.) be released or blocked before equipment is locked out for repairs? □ Are appropriate employees provided with individually keyed personal safety locks? □ Are employees required to keep personal control of their key(s) while they have safety locks in use? □ Is it required that only the employee exposed to the hazard can place or remove the safety lock? □ Is it required that employees check the safety of the lockout by attempting a startup after making sure no one is exposed? □ Are employees instructed to always push the control circuit stop button prior to re-energizing the main power switch? □ Is there a means provided to identify any or all employees who are working on locked-out equipment by their locks or accompanying tags? □ Are a sufficient number of accident prevention signs or tags and safety padlocks provided for any reasonably foreseeable repair emergency? □ When machine operations, configuration, or size require an operator to leave the control station and part of the machine could move if accidentally activated, is the part required to be separately locked out or blocked? □ If equipment or lines cannot be shut down, locked out and tagged, is a safe job procedure established and rigidly followed? 60 “Electrical Safety in the Workplace” Making sure your worksite has SMART Goals Your worksite may need to establish SMART Goals that allow you to carry out your ideas These will be based on the actions that you have written on your Post-It Notes Your action steps or goals must be: Specific Measurable Assigned Realistic Timed Is it Specific? Is it Measurable? Is it Assigned? Is it Realistic? Does it have a Timeline? ¾ Using the list of characteristics above, add details to make to your Post-It Notes to make the action items SMART + Is it specific enough? (i.e “Label all disconnects” is usually not specific enough! Locate them where on the panel / disconnect? What information you want on the label?) + Is it measurable? + Who’s responsible for the follow through? (“Which individual is assigned to ensure that the task gets done? Who will help him or her in what specific ways?) ª How long will it take to get done from the time it starts? Once you’ve plotted a start date on your schedule, set a deadline for having it done! ¾ You may find that one Post-It note action has become three of four! Use one note for each separate assignment needed to accomplish the goal Once you’ve finished developing your list of SMART goals or action items, plot them out on the flipchart grid and check them again to see how realistic a plan your plan is 61 “Electrical Safety in the Workplace” Developing a Plan Month # Month # Month # Month # Month # Month # Month # Month # Month # Month # 10 Month # 11 Month # 12 62 “Electrical Safety in the Workplace” Excerpt from "American Electricians' Handbook" 7th Edition, 1953, McGraw-Hill: "Electricians often test circuits for the presence of voltage by touching the conductors with the fingers This method is safe where the voltage does not exceed 250V and is often very convenient for locating a blown-out fuse or for ascertaining whether or not a circuit is alive." 63 ... Safety in the Workplace? ?? limiting exposure in all electrical installations, including workplaces OSHA has determined that electrical hazards in the workplace pose a significant risk of injury... Determine degree and extent of hazard and PPE required 44 ? ?Electrical Safety in the Workplace? ?? 45 ? ?Electrical Safety in the Workplace? ?? Correct way to verify! 46 ? ?Electrical Safety in the Workplace? ??... Think of the bridge as a garden hose The current of electricity is the water flowing in the hose and the water pressure is the voltage of a circuit The diameter of the hose is the determining