Electrical Safety/Powerline Hazards

Transcription

1 Electrical Safety/Powerline Hazards Latest revised date: October 26, 2011 Page 1 of 11

2 1.0 Introduction Memorial will ensure that any employee or contractor who is required to work with electrical conductors, apparatus, or equipment is appropriately trained and qualified to carry out the work safely. 2.0 General 2.1 All electrical installations, equipment, apparatus, and appliances shall be in conformity with the requirements of the Provincial Electrical Code as adopted in the Electrical Regulations. 2.2 Only workers qualified to work on electrical conductors and equipment shall be authorized to do so. Other workers may work on electrical conductors or equipment providing that they are under the direct supervision of a qualified worker. 3.0 Responsibility 3.1 The departmental manager is responsible for implementation of this procedure within the department. The final responsibility for ensuring that the procedure is followed in the workplace rests with the immediate supervisor. 3.2 Persons coordinating construction with outside contractors shall ensure that contractors are aware and follow this procedure. 4.0 Protective Equipment 4.1 Rubber gloves, shields, safety glasses, flame retardant clothing, and other necessary safety equipment shall be used by workers engaged in working on energized electrical conductors or equipment operation at a voltage greater than 250 volts to ground. Electrical protective equipment shall be maintained in a safe, reliable condition. Insulating equipment shall be inspected for damage before each day's use and immediately following any incident that can reasonably be suspected of having caused damage. Insulating gloves shall be given an air test, along with the inspection. 4.2 Insulating equipment with any of the following defects may not be used: A hole, tear, puncture, or cut; Ozone cutting or ozone checking (the cutting action produced by ozone on rubber under mechanical stress into a series of interlacing cracks); An embedded foreign object; Latest revised date: October 26, 2011 Page 2 of 11

3 Any of the following texture changes: swelling, softening, hardening, or becoming sticky or inelastic. Any other defect that damages the insulating properties. 4.3 Insulating equipment shall be stored in such a location and in such a manner as to protect it from light, temperature extremes, excessive humidity, ozone, and other injurious substances and conditions. 4.4 The maximum voltage permitted for the use of rubber gloves, shields, and other necessary safety equipment while working on energized electrical conductors shall be 3000 volts to ground. 4.5 A worker shall not work on an energized electrical conductor or equipment operating at more than 3000 volts unless satisfactory procedures are used or the workers are provided with and trained in the use of special tools that are approved for use. 4.6 When working near exposed energized conductors or circuit parts, each employee shall use insulated tools or handling equipment if the tools or handling equipment might make contact with such conductors or parts. If the insulating capability of insulated tools or handling equipment is subject to damage, the insulating material shall be protected. 4.7 PPE inspections shall meet or exceed the inspection standards given below: Air testing of gloves is mandatory, (Use ASTM F 496 test procedure) Follow ASTM F 496, Specification for In-Service Care of Insulating Gloves and Sleeves Refer to ASTM F 1236, Standard Guide for Visual Inspection of Electrical Protective Rubber Products for Additional Information Latest revised date: October 26, 2011 Page 3 of 11

4 5.0 Testing of Rubber Protective Equipment and Hot Sticks 5.1 Testing of rubber protective gloves must be carried out by an approved testing authority, in accordance with the American Society for Testing and Materials (ASTM) D , Specification for Rubber Insulating Gloves. 5.2 Testing Schedule All classes of rubber gloves will be tested every 6 months by an approved testing agency Insulating equipment shall be inspected for damage before each day's use and immediately following any incident that can reasonably be suspected of having caused damage. Insulating gloves shall be given an air test, along with the inspection. Use ASTM F 496 test procedure Insulating equipment found to have other defects that might affect its insulating properties shall be removed from service, tagged with description of defect, and returned for testing Insulating equipment shall be cleaned as needed to remove foreign substances Insulating equipment shall be stored in such a location and in such a manner as to protect it from light, temperature extremes, excessive humidity, ozone, and other injurious substances and conditions Protector gloves shall be worn over insulating gloves, except with Class 0 gloves, under limited-use conditions, where small equipment and parts manipulation necessitate unusually high finger dexterity. (Note: Extra care is needed in the visual examination of the glove and in the avoidance of handling sharp objects). 6.0 Eye, Face and Head Protection 6.1 Employees shall wear nonconductive, CSA approved, Class E head protection wherever there is a danger of head injury from electric shock or burns due to contact with exposed energized parts. 6.2 Employees shall wear protective equipment for the eyes or face wherever there is danger of injury to the eyes or face from electric arcs or flashes or from flying objects resulting from electrical explosion. The protective eyewear will provide protection both from impact arching/flashing. Latest revised date: October 26, 2011 Page 4 of 11

5 7.0 Working Alone Prohibited 7.1 Work shall not be done on an energized electrical conductor or equipment that has a voltage of more than 750 volts unless 2 or more workers are present while the work is being performed. 7.2 In tunnels and manholes, work shall not be done on energized electrical conductors or equipment having a voltage of more than 250 volts unless there are at least 2 qualified workers present. (Exception: The prohibition to working alone on voltages over 750 volts requiring 2 or more workers will not apply to the fusing of transformers where the transformer fuses are accessible without passing or reaching past electrical conductors or equipment carrying more than 250 volts. Also it does not apply to work done with special tools that are designed for the purpose and that are used by workers who have been trained in the use of these tools). 7.3 Work shall not be done in or around an area or structure in proximity to energized electrical conductors, or on equipment that is normally isolated by position or elevation, unless the electrical conductors or equipment are provided with guards that will effectively prevent contact by a worker, or by equipment being used or handled. Notices reading "DANGER - HIGH VOLTAGE" shall be placed in prominent positions in proximity to energized electrical equipment operating at over 750 volts which may be accessible to workers. 8.0 Working on De-energized Equipment 8.1 Before workers are required or permitted to work on a part of an electrical power system that, for reasons of safety, must be handled in a de-energized condition, the worker in charge shall ensure that the part of the system being worked on is de-energized and grounded. Controls are to be tagged and locked, as per Memorial s Lockout Tagout policy, to prevent the system being re-energized. 8.2 Before commencing work on the de-energized part of the system, the worker in charge shall, by grounding or other effective means, ensure that the part or section is de-energized and grounded and that all workers are protected against reenergization. 8.3 Control devices shall not be reopened except as per Lockout Tagout procedure. Latest revised date: October 26, 2011 Page 5 of 11

6 9.0 Electrical Tunnels and Support Structures 9.1 All tunnels and manholes that contain electrical conductors and equipment, and in which workers may have to work, shall be kept in safe and sanitary condition, free from stagnant water, seepage, or other drainage dangerous to health. 9.2 All electrical distribution switches and controls shall be clearly marked to indicate the machinery or equipment which they serve Powerline Hazards 10.1 A person shall not operate a mobile crane, boom truck, or similar equipment without having first completed a safety training program on power line hazards as prescribed by the Workplace Health, Safety and Compensation Commission The following shall not be permitted to occur where overhead or underground conductors are located that are capable of energizing the material, mobile equipment, or its load: Storage or piling of material Erection or dismantling of scaffolds Operation of mobile cranes, boom trucks, or similar equipment Safe clearance distances shall be obtained from the power utility before commencing any of the aforementioned work and operations If written clearances are unavailable from the power utility, a minimum 5.5 meters shall be maintained When workers are required to work in an area where overhead or underground electrical conductors are located, the University shall be responsible for: Maintaining the minimum clearance distance; and Ensuring that no material or equipment is allowed to be handled or operated within the minimum clearance specified Assurance in writing signed by the workers controlling the electrical system shall be obtained before work commences, and this assurance shall state that during the time that the work is to be carried out the electrical conductors will be: De-energized and grounded; Effectively guarded against contact; or Displaced or rerouted from the work area. Latest revised date: October 26, 2011 Page 6 of 11

7 10.6 The written assurance shall be available for inspection at the work project and shall be made known to all workers who may be permitted access to the area within which equipment or materials are to be moved or stored. If the electrical conductor is not de-energized, or if written assurance is unobtainable before work commences: The area within which equipment or materials are to be moved shall be barricaded and supervised to restrict entry to only those workers necessarily engaged in the work; A worker shall be designated as a signal person whose sole task during the movement of equipment or material is: (i) To observe the relative position of the moving equipment or material and the electrical conductors, and (ii) To order the movement stopped at any time that contact appears probable, or when conditions arise which prevent the signal person from properly performing his or her task; While equipment or material is in motion in an area in proximity to energized electrical conductors, a worker other than equipment operators shall not touch or be permitted to touch a part of the equipment or material; and A worker shall not move or be permitted to move a load or a rigging-line from its position of natural suspension when it is in proximity to energized electrical conductors. Latest revised date: October 26, 2011 Page 7 of 11

8 11.0 Painting in Proximity to High Voltage Electrical Current 11.1 Workers shall not use oil-base paint or other volatile flammable substances in electrical substations or a confined area where high voltage electrical current passes through If oil-base paints or other volatile flammable substances are to be used, Memorial shall ensure the following: There is adequate ventilation; High voltage electrical current is diverted; and Outward swinging doors are installed in entrances and/or exits Ladders in Proximity to Electrical Equipment 12.1 Where ladders are used in the vicinity of electrical currents, they must be of a non-conductor type and caution shall be taken to ensure that the necessary clearance from electrical conductors is maintained Metal ladders or wire reinforced wooden ladders shall not be used in proximity to energized electrical equipment The purchase of electrically conducting ladders is prohibited. All existing electrically conducting ladders shall be destroyed when its life span has expired Working on machinery 13.1 The cleaning, piling, or adjusting of moving machinery is prohibited when contact with moving parts could injure workers When machinery or equipment is shutdown for maintenance or repairs, work shall not be carried out until all parts, extensions, and attachments have been secured against inadvertent movement, hazardous conditions have been removed, and lockout procedures have been applied When workers are required to work in a vessel that is connected to a system of piping, the control valves shall be padlocked or the piping disconnected or other means adopted which will prevent a substance flowing into the vessel in which they are working. Latest revised date: October 26, 2011 Page 8 of 11

9 14.0 Electrical Lockout and Tagout 14.1 Before commencing maintenance or repair work on power-driven machinery or equipment, the control devices shall be locked in an inoperative position and a tag and lock shall be attached prohibiting the operation of the control device Each worker or crew of workers working independently of each other shall be responsible for tagging and locking the control devices and the removal of the tags and locks After tagging and lockout procedures have been applied, machinery and equipment shall be checked to ensure that the machinery or equipment cannot be operated Tags and locks shall only be removed by the person who installed them, or in an emergency, by a supervisor who shall first ensure that the machinery or equipment can be operated safely and the originating person has been accounted for. (Refer to Lockout Tagout Procedure.) 14.5 "Lockout device" shall mean, in the case of electrical controls, the isolating switch or circuit-breaker controlling the flow of current to the branch-circuit which supplies power to the machinery or equipment. The locking out of individual control buttons or switches on a console shall not be accepted as compliance with these regulations Electrical Installations 15.1 Electrical wiring and equipment, located where flammable materials are sprayed, shall meet the requirements of the Canadian Electric Code and regulations under it. Latest revised date: October 26, 2011 Page 9 of 11

10 16.0 Proper Grounding of Equipment and Tools 16.1 Properly grounded electrical equipment can offer protection if the equipment should malfunction electrically If electric tools state doubly insulated on the manufacturer's tag, this means there is insulation on the inside of the tool to protect from shock. This type of tool will only have a two-prong plug. If the tool doesn't state that it is doubly insulated, then you must have a third prong on the plug. This third prong, or ground prong, plugs your tool into ground or earth so that in the event of a malfunction, the electricity will go through this ground prong to earth and bypass your body. If the prong is broken off, there is no protection inherent in the tool, and the tool should not be used A Ground Fault Circuit Interrupter (permanent or portable) shall be used where there is a chance contact could be made with the moisture on the ground, such as working outside Location Check 17.1 Prior to undertaking any excavation on campus, the person in charge of the project shall consult with the Project Design and Drafting Office to determine if any underground utilities are located in the planned excavation area. Determination shall be made by consulting with appropriate site plans that are kept in the Project Design and Drafting Office. Further cross-reference checks can be made with sections having information on specific utilities; e.g., Electrical, Plumbing, in situations where information may not be complete If utilities are suspected and there is no information provided, appropriate detection instruments shall be used to assist in location Training 18.1 Only competent personnel shall conduct work on or near exposed energized parts A competent person is defined as follows: A competent person is a person who has been trained to avoid electrical hazards when working on or near exposed energized parts. A competent person is: Familiar with the safety related work practices required in 29 CFR ; Familiar with this policy; Familiar with organization specific safe work procedures (these procedure must be written and approved); Latest revised date: October 26, 2011 Page 10 of 11

11 Able to distinguish between exposed live parts of electrical equipment; Knowledgeable of the skills and techniques used to determine the nominal voltages of exposed parts; Knowledgeable of approach distances to which a Qualified Person will be exposed (see Table 1.0); and Trained in First Aid and CPR (with emphasis on electrical injuries) Unqualified personnel shall not work on or near exposed energized parts. Exception: The equipment or electrical parts they are to perform work on are deenergized as per Memorial s Lockout Tagout policy A qualified person has verified that the equipment or electrical parts is deenergized An unqualified person is someone who has little or no training regarding electrical hazards. Minimally, any person working near electrically energized parts shall receive training and instruction so that they become familiar with any electricalrelated safety practice that is necessary for their safety. Legislative Reference: OH&S Regulations Part XXVI 477 to 510 Latest revised date: October 26, 2011 Page 11 of 11