Corporate Safety Procedure Low Voltage Electrical Testing for De-Energisation and Re-Energisation. Table of Contents

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1 Table of Contents 1. Purpose and Scope References Definitions and Abbreviations Authorised Person Instructed Person Person in Control of electrical equipment Safety Observer Personal Protective Equipment/Tools Responsibility/Obligations Obligation of employer or self-employed person Obligation of person in control of electrical equipment Obligations of worker Actions Prior to starting task Electrical worker to check equipment/ppe Isolation is performed Restoration of supply Calibration and Testing of Electrical Equipment Testing of Electrical Safety Equipment Record Keeping Related Documents... 9 Document Number: PRO Version Date: 01/08/2011 Page: 1 of 9

2 1. Purpose and Scope The purpose of this procedure is to document the steps electrical workers shall use when performing low voltage electrical testing for de-energisation or re-energisation. The procedure will assist with ensuring the safety of electrical workers while performing this task and provide tests and guidelines that will ensure equipment is returned to service in a safe condition. Section 12, Part (1) of the Electrical Safety Act 2002 (Qld) (LEG-00166) requires: An employer or self-employed person must ensure that, unless the circumstances required under this division for the performance of live work apply, live work is not performed. 2. References AS/NZS 4836:2011 Safe working on low voltage installations Electrical Safety Regulation 2002 (Qld) (LEG-00192) Seqwater Energy Tag and Lockout System Procedure 3. Definitions and Abbreviations 3.1 Authorised Person An authorised person for an electrical part is a person who has enough technical knowledge and experience to do the work and has been approved by the person in control of the electrical equipment to do the work that involves coming near or in contact to electrical parts. 3.2 Instructed Person An instructed person for an electrical part means a person who is acting under the direct supervision of an authorised person for the electrical part for the purposes of training. Refer to Section 209 of the Electrical Safety Regulations 2002 regarding the requirements for supervising of training persons (apprentices). 3.3 Person in Control of electrical equipment The person in control of the electrical equipment may be a plant operator or manager, control room operator or coordinator. 3.4 Safety Observer A Safety Observer is a person who competent to assist in this field of work and has completed a switchboard rescue course and resuscitation training in the last 6 months and is competent in that training. 4. Personal Protective Equipment/Tools The PPE used during this procedure shall be: Long sleeve shirt buttoned at the wrist and neck, long trouser cotton or flame retardant clothing, safety eyewear and safety footwear. The minimum tools/equipment required shall be category 3 voltage detection devices with type A probes and temporary barriers to prevent public access (if applicable). Document Number: PRO Version Date: 01/08/2011 Page: 2 of 9

3 5. Responsibility/Obligations 5.1 Obligation of employer or self-employed person 1) This section applies to an employer or self-employed person. 2) A person to whom this section applies has an obligation to ensure that the person s business or undertaking is conducted in a way that is electrically safe. 3) Without limiting subsection (1), the obligation includes: (a) ensuring that all electrical equipment used in the conduct of the person s business or undertaking is electrically safe; and (b) if the person s business or undertaking includes the performance of electrical work, ensuring the electrical safety of all persons and property likely to be affected by the electrical work; and (c) if the person s business or undertaking includes the performance of work, whether or not electrical work, involving contact with, or being near to, exposed parts, ensuring persons performing the work are electrically safe. 5.2 Obligation of person in control of electrical equipment 1) A person in control of electrical equipment has an obligation to ensure the electrical equipment is electrically safe. 2) Subsection (1) does not apply to the person in control of electrical equipment to the extent that the electrical equipment (a) Is located at premises in which the person lives; or (b) Forms part of the works of an electricity entity. 5.3 Obligations of worker A worker at a place where electrical equipment is located has the following obligations: (a) To comply with the instructions for the electrical safety of persons and property at the place given (i) By the worker s employer; and (ii) To the extent the instructions are not inconsistent with instructions given by the worker s employer, by the person in control of the electrical equipment; (b) To use personal protective equipment, if (i) The protective equipment is provided by the worker s employer or the person in control of the electrical equipment for electrical safety purposes; and (ii) The worker is properly instructed in the use of the protective equipment provided; Document Number: PRO Version Date: 01/08/2011 Page: 3 of 9

4 6. Actions (c) Not to wilfully interfere with or misuse anything provided for electrical safety at the place; (d) Not to wilfully place any person, including the worker, at the place in electrical risk. 6.1 Prior to starting task If members of the public are present, a barrier system shall be erected to prevent entry to the work area. The electrical worker shall ensure members of the public are kept clear of the switchboard area. If weather conditions are severe (heavy driving rain) work shall not proceed as this may increase the risk of workers receiving an electric shock. If weather conditions are mild (light falling rain, no wind) a cover or umbrella shall be erected to protect the worker and equipment getting wet. Any clarification as to whether work should proceed shall be directed to the person in control of the electrical equipment. (Note: The person in control may be able to divert flow, order tankers to control flow until environmental conditions are suitable). The work area shall be clear of obstructions. The low voltage rescue kit should be checked for completeness and condition. Low voltage rescue gloves (Class O ) should be checked for appropriateness of work being undertaken. Only authorised licenced electrical workers, instructed persons or restricted electrical workers shall perform electrical de-energisation/re-energisation work. Restricted electrical workers shall only isolate, test for de-energisation and re-energise equipment that is incidental to their field of work. For example, a fitter removing a pump may need to electrically isolate the equipment prior to removal. Restricted electrical licence holders shall be aware of the requirements of exclusion zones in Schedule 2 of the Electrical Safety Regulation 2002 (Qld) (LEG-00192). Before electrical isolation begins the worker shall consult the person in control of electrical equipment and/or an electrical diagram for the electrical installation to ensure the correct equipment is isolated. The correct point of positive isolation of the equipment shall be identified prior to testing for dead. The voltage detector used to check for de-energisation shall be checked to ensure it is capable of detecting the voltage being tested and is set to the correct range. Document Number: PRO Version Date: 01/08/2011 Page: 4 of 9

5 6.2 Electrical worker to check equipment/ppe Workers shall remove any metal rings, bracelets, watches or exposed body jewellery that may have the potential to come in contact with an electrical part. The following PPE shall be checked and worn: Full-length non-flammable clothing, safety footwear and safety eyewear. An electrical worker s work gloves should be: Cloth Inner Class OO rubber Leather outer Other PPE may be required to be worn. A voltage detection device appropriate for the voltages being tested and able to give a clear indication to the user shall be used. Testing instruments for voltages shall have suitably insulated and fused test leads. Use of voltage indicators that detect an electric field may not be suitable for test for dead purposes. The operator of the test instrument shall be familiar with its use. 6.3 Isolation is performed No electrical part shall come into contact with any part of the electrical worker unless it is tested and proven isolated with appropriate test equipment that has been verified as working before and after the testing of the electrical part. The electrical worker shall positively identify the isolation point of the equipment being worked on by either consulting with the person in control of the electrical equipment, site documentation or by knowledge from training and/or experience. The electrical worker shall isolate the electrical equipment required to be isolated by operating a switch, circuit breaker or isolation point that shall remove the electrical supply by creating an air gap or barrier that shall prevent the electrical supply from coming in contact with the isolated equipment. A personal danger tag shall be attached by the electrical worker to the point of positive isolation and where possible, a personal isolation lock shall be attached to the positive isolation point to prevent inadvertant operation of the isolation device. If a lock cannot be attached to the point of positive isolation, the cables shall be removed from the electricity supply. Refer to the Seqwater Tagout Lockout System procedure. Further non-positive isolation may be performed to further safeguard electrical workers from inadvertent equipment operation, where possible. An example of this may be removal of circuit control fuses from a motor starter. If a lock cannot be attached to the point of isolation and/or removal of cables or busbars are not feasible, a non conformance report shall be submitted by the electrical worker so that sites without locking facilities can be identified. Where the cable is removed from the source of supply, a personal danger tag shall be attached to the cable and the cable shall be terminated correctly. The worker shall note any phase coding or direction. Document Number: PRO Version Date: 01/08/2011 Page: 5 of 9

6 The electrical worker shall test the test instrument on a known voltage supply source and verify a positive (voltage present) indication. This should be a source that the worker has clear access to and does not involve coming close to or in contact with untested electrical parts or areas of high fault current. Restricted electrical licence holders may need to test voltage detection devices at a low fault current voltage source such as a powerpoint. Note that a phase to earth test may trip circuits supplied by Residual Current Devices (RCD) when using some types of voltage detection devices. The electrical worker shall test the electrical parts required to be touched by a phase to phase, phase to neutral or phase to earth test. Any indication other than a no voltage (negative) state shall be investigated. Because phase to earth testing may trip RCD s, the electrical worker shall exercise care not to trip possible essential circuits that an RCD may supply. There may also be 2 sources of supply, multi voltage types, backfeeds or incorrect isolation of supply. Care shall be exercised when testing stored voltage sources such as variable speed drives or capacitor banks. After the previous test, the electrical worker shall immediately re-test the test instrument for operation on a known voltage supply to prove the test instrument is operational and this should indicate a positive (voltage present) indication. If a negative indication for voltage levels is shown on the test instrument, the cause shall be investigated and the electrical parts shall still be treated as live. Wherever possible, the electrical isolation shall then be tested by attempting to start the equipment. Attempting to start the electrical equipment shall be achieved by manual operation. Electrical workers should be aware that isolators can fail and that some equipment may not start until a certain condition exists, eg. a limit switch is tripped. After the above checks are made, the electrical worker shall then proceed with the electrical work. All hazards or electric shocks shall be reported to the coordinator/ supervisor or safety adviser as soon as possible. The appropriate Seqwater Incident report form must be completed. 6.4 Restoration of supply After the electrical work is completed, the electrical worker shall perform any required electrical tests prior to restoration of supply. This may include physical inspection, earthing and/or insulation resistance tests, polarity and RCD tests. After testing is completed, all person, tools and equipment shall be removed from the work area. If the electrical equipment is to be placed back into service, the electrical worker shall remove any personal isolation locks or personal danger tags from the positive isolation point and reconnect the equipment to the electrical supply. Safety glasses shall be worn while equipment is being re-energised. Document Number: PRO Version Date: 01/08/2011 Page: 6 of 9

7 If re-energisation voltage checks are required to be performed, safety glasses and electrical working gloves shall be worn. The electrical worker shall, if required, inform other workers and/or the person in control of equipment that the equipment is about to be re-energised. Any equipment not able to be put back into service shall be isolated from the supply. Refer to the Seqwater Energy Tag-out Lockout System procedure. All cables not connected shall be terminated with appropriate connectors. No bare conductors shall be present. After work is complete, all covers and doors shall be placed securely in place, with switchboard external doors locked or bolted into place. Equipment placed back into service shall be checked that it is functioning correctly. 6.5 Calibration and Testing of Electrical Equipment For the purposes of this section, electrical test equipment includes any item of equipment used to test or otherwise determine the status of an electrical item. An electrical test equipment register is to be maintained for all electrical test equipment at each site where Seqwater electrical workers are based Testing Testing of Seqwater electrical test equipment is to be undertaken every six (6) months. Results of the tests are to be recorded within the electrical test equipment register. The electrical test equipment register is to be maintained at each site where Seqwater electrical workers are based. Test equipment used for testing on low voltage circuitry shall be tested to 1000 volts AC and 1500 volts DC Calibration Calibration of electrical test equipment is to be undertaken as per manufacturers requirements for each type of test equipment used, or every 12 months, whichever is the shorter. Results are to be recorded within the electrical test equipment register Inspection Prior to each use, test instruments and their associated leads, clips, sockets, probes are to be inspected for any damage to insulation. Each electrical test instrument is to have a durable sticker placed on it to indicate that it has been tested. The sticker is to contain information about who performed the test, when the next testing is due and the name of the company that performed the test. Document Number: PRO Version Date: 01/08/2011 Page: 7 of 9

8 6.6 Testing of Electrical Safety Equipment Each item of electrical safety equipment shall be tested every six (6) months. Items that pass the test are to be tagged with the next test date and returned to service. Any item that does not pass the test is to be removed from service. After repair an item must be tested before being returned to service. Test records shall be retained for 7 years. Whenever an item of equipment is tested by an external organisation a written test report will be required. The testing organisation will be required to provide written details of test methods Equipment to be inspected Insulating mats and covers Insulating mats are to be inspected every six (6) months and tested in accordance with AS/NZS 2978 Insulating Mats for Electrical Purposes. Mats are to be washed with water and soap or detergent, stretched and examined for the following: Blisters, cracks, cuts or holes Embedded foreign matter Defective fastenings Insulating gloves Insulated gloves are to be washed and inspected every six (6) months in accordance with AS2225 Insulating Gloves for Electrical Purposes, and replaced periodically, but at intervals no longer than every 12 months Low voltage rescue kit A rescue kit shall contain the following equipment and be inspected every six (6) months to ensure all items are present, items are in good condition and gloves are in-test: Insulated crook Insulating gloves in protective cover. Gloves shall be tested every six months as required for other insulating gloves. Isolate Here in Emergency sign. Burn dressings and fire blanket Torch 7. Record Keeping All records are required to be kept for a seven (7) year period. An electrical equipment register is to be kept on site of all Seqwater owned electrical test equipment that contains the following; Record of formal inspections and tests Document Number: PRO Version Date: 01/08/2011 Page: 8 of 9

9 Record of calibrations for each instrument requiring calibration Record of repairs for each instrument. 8. Related Documents PRO Corporate Safety - Energy Tag and Lock out Procedure AS/NZS 4836:2011 Safe working on low voltage installations. Queensland Electrical Safety Act and Regulations Document Number: PRO Version Date: 01/08/2011 Page: 9 of 9