CHAPTER 12:

---

A. Policy

---

---

B. Responsibilities 

---

1. Supervisor
1. Anticipates work hazards and ensures that relevant safeguards are utilized.
2. Ensures that all employees are properly trained and instructed in the safe operation of electrical equipment and aware of all hazards associated with the use of these electrical devices.
3. Writes job risk assessments with input from the employee and assistance from the site safety advisor.
4. Initiates any necessary administrative action required to enforce safety practices.
2. Employee
1. Follows the JAC's electrical safety policies and procedures and instructions of supervisor.
2. Brings to the attention of the supervisor potential hazardous situations such as discrepancies between instruction, procedures, policies and manual, faulty equipment,and misapplication of devices.
3. Takes electrical equipment out of service if it is known to be malfunctioning and ensures that it is repaired or replaced before use.
3. Site Safety Advisor
1. Assists supervisors in defining hazardous operations, designating safe practices and selecting proper application of devices.
2. Participates in reviewing and approving standard operating procedures.
3. Evaluates potential electrical hazards during safety tours to insure compliance with JAC policy and other safety guidelines.
4. Requests support from electrical group on hardware and equipment testing, tagging out of unserviceable equipment, and taking corrective action where necessary.

---

C. Training Requirements 

---

See also Chapter 1 section C

1. Employees who face a higher than normal risk of contact with electrically energized parts 50 volts or more to ground shall be trained in compliance with OSHA Regulation 29 CFR 1910 - Subpart S and 29 CFR 1926 - Subpart K.
2. Supervisors shall have at least the same level of OSHA-based electrical safety training as the workers for whom they are responsible or whose work they plan or supervise.
3. If the worker is unfamiliar with the construction or operation of the equipment or the hazards associated with the task, additional training may be required. In these cases, the supervisor must document the instruction the worker receives in the use of safe work practices for the voltage levels to be encountered and the selection, inspection, and use of Personal Protective Equipment (PPE).

---

D. Procedures 

---

1. De-energizing Live, Exposed Parts
1. Energized parts that operate at less than 30 volts or parts that have less than 1 milliamp of current potential need not be de-energized if there will be no increased exposure to electrical burns or to explosion due to electric arcs.
2. Electrical parts operating at 30 volts or more with a current capacity of 1 milliamp or more shall be de-energized before they are maintained or repaired, or parts are exposed within the limited approach boundary. Lockout tagout procedures must be used except when the equipment has a cord and plug which is under the direct control of the qualified person performing the work.
3. Exceptions to this rule are as follows:
1. De-energizing would create increased or additional hazards which include interruptions of life support systems, shutdown of hazardous location ventilation equipment, removal of illumination for an area, or deactivation of emergency alarms.
2. De-energizing is infeasible due to equipment design or operational limitations which include:
• Testing of electric circuits that can only be performed with the circuit energized.
• Work on the circuits that form an integral part of a continuous process that would otherwise need to be completely shut down, creating a greater hazard, in order to permit work on one circuit or piece of equipment.
4. If de-energizing parts will introduce additional risk or is impractical due to the design of the equipment or operational limitations, a written risk assessment shall be required for that work.
5. Release stored electrical energy which might endanger personnel. Discharge capacitors with a device approved for this use and short-circuit and ground high-capacitance elements if the stored electric energy might endanger personnel.
6. Verify that the field conditions and documents match and resolve any differences before continuing the work. If there are any unresolved differences which could result in an inadvertent re-energization from another source, take extra precautions during the potential exposure. Precautions include verifying the circuit is de-energized and conducting work using the safeguards required for energized systems for the remainder of the work.
2. Safe Practices for Work With Exposed, Energized Electrical Parts
1. "Low voltage" systems. Where a system incorporates a power supply which works on mains voltage but supplies a low voltage output, then the system may be worked on as a low voltage system provided that all of the high voltage parts are covered.
2. Work between 30 V and 150 V: Work on exposed energized electrical parts between 30V and 150V and above 1 milliamp capacity may be carried out without further preparation only by one of the authorised staff on the list in addendum 1. If the work is unusual or especially demanding then a risk assessment shall be considered.
3. Work above 150V: A written risk assessment shall be done for jobs requiring working on exposed energized electrical parts above 150 V and 1 milliamp, and consideration shall be given to at least the following areas:
1. The written risk assessment shall document the hazards and the required Personal Protective Equipment (PPE) for each job. PPE may include voltage-rated rubber blankets, gloves, pads, tools, or insulated protective barriers that provide protection.
2. Do not wear or carry in clothing pockets any conductive accessories (rings, watches bracelets, metal frame glasses, metal hats etc.) where they may make contact with exposed, energized parts.
3. Wear natural fiber clothing whenever you may be exposed to voltages of high energy circuits above 150 volts to ground.
4. Inspect the work area for sufficient illumination, working space, and safe access, and verify that no undocumented risks exist.
5. Cabinet doors shall open at least 90 degrees. There shall be adequate distance from electrically energized parts to grounded structures or items.
6. Near exposed energized parts, use only portable ladders with dry, nonconductive side rails.
7. Use signs, barricades, or attendants to isolate the work area and warn others of the exposed energized electrical circuits. Electrical safety warning signs must be worded: DANGER - ELECTRICAL HAZARDS - AUTHORIZED PERSONNEL ONLY
8. If you receive any electrical shock (other than static), stop work and report the incident to your supervisor. Seek medical attention if warranted.
9. A backup person may be required, to observe the worker to ensure adequate clearances and to perform emergency rescue if required. The person must have been trained in first aid and CPR, or able to call on such assistance within the facility.
3. Testing and Troubleshooting on Live, Energized Parts
1. Testing and troubleshooting on live, energized parts is allowed.
2. If a problem is discovered during the troubleshooting and either a component must be removed or rework must be performed, this is no longer troubleshooting. At that time, the circuit must be de-energized and locked out.
3. When a fuse in a portable piece of equipment fails, the cause shall normally be investigated before the fuse is replaced. If there are no obvious problems, it is permissible to change the fuse provided the following checks are made with the unit unplugged:
• Check that the chassis is connected to the safety ground pin in the plug
• Check that once the fuse has been replaced and BEFORE the unit is plugged in, there is no short between the chassis and the power line.
4. Non-conductive Protective Equipment
1. Store and use according to the manufacturer's recommendation.
2. Inspect protective equipment before each use to verify the item is in satisfactory condition and has been tested as required. Inspect rubber gloves for holes and air test before using. Rubber protective equipment shall be inspected and tested at the manufacturer's recommended interval, or more often if necessary.
3. Inspect voltage rated tools for defects and surface contamination such as moisture or dirt before each use.
4. Do not rely on insulated tools alone for complete protection.
5. Electrical Test Equipment
1. Visually inspect electrical test equipment immediately before use and do not use if defective. Identify defective test equipment by tagging it out of service and repair or dispose of properly.
2. Use electrical test equipment only for intended applications. Read the operating instructions and limitations for the test equipment.
3. Check electrical test equipment for proper operation immediately before and after use when verifying that circuits are de-energized. When performing zero energy checks, ensure that stored electrical or mechanical energy cannot re-energize the circuit.
6. Requirements for GFCI Protection of Personnel
1. Use ground fault circuit interrupters (GFCI) on 120-volt circuits in damp or wet work areas and outdoors.
2. Use GFCI for all extension cords except where used for extended service with equipment with plug and cord and not likely to be damaged.
3. Test portable GFCIs before each use. If any damage is evident that might expose people to injury, remove the item from service.
4. Use double insulated tools and equipment when appropriate. Double insulated tools do not require the use of a GFCI.
7. Requirements for Flexible Cords and Cables
1. Extension cord sets are not to be used as a substitute for the permanent wiring of a building.
2. Use flexible cords suitable for conditions of and location of use. Flexible cord sets used with grounding-type equipment must contain an equipment grounding conductor.
3. Protect flexible cords and cables from damage by foot traffic, vehicles, sharp edges, pinching, and improper storage.
4. Inspect all extension cords before use and discard damaged cord sets or have any break in the insulation repaired by a qualified person so that it is equal to or better than the original.
8. Requirements for Drilling into Walls, Floors, or Outdoor Slabs and Excavations Containing Buried Electrical Cables
1. As appropriate, review all drawings and documentation. Visit the job site to determine if obstructions are in the drilling path before starting the job.
9. National Electrical Code (NEC) Requirements
1. Install all electrical equipment in accordance with NEC requirements.
2. All electrical installations and modifications will be inspected as required by code. The Chief Engineer's interpretation of code requirements shall be final.
10. Soldering
1. Only solder in well ventilated area
2. Utilize caution due to heating element of soldering equipment.
3. Wear eye protection whenever soldering
11. Tripped, Locked or Tagged Circuit Breakers
1. Where a panel board circuit breaker of greater than 20 Amps has tripped, operation by non- qualified JAC personnel is prohibited except in case of personal emergency or when the overload that caused the breaker to trip is known and corrective action has been taken. Otherwise, a qualified person must investigate the fault before operating the circuit breaker.
2. Switching devices which are tagged or locked shall not be operated until tag is removed by issuer or the alternative steps detailed in Chapter 13 have been followed.
12. Permanently Installed Fuses
1. Fixed power line fuses shall not normally be changed except by qualified personnel. It is permissible for the Telescope System Specialist (TSS) to change the fixed fuses at JCMT under the following circumstances:
• Contact must be made with Site Safety Advisor (SSA).
• Steps must be taken to establish what caused the fuse to blow and to fix the problem.
• The TSS may choose to replace the fuse under the telephone guidance of the SSA if they are both satisfied that it is safe to do so.

---

E. Definitions 

---

1. Exposed parts: Energized electrical parts capable of being inadvertently touched or of being approached closer than a safe distance (see Table 1) by a person. It is applied to parts not suitably guarded, isolated, or insulated.
2. Ground-fault circuit-interrupter: A device intended for protecting personnel, designed to de-energize the electric circuit within an established period of time, when a current to ground exceeds some predetermined value that is less than the current required to operate the overcurrent protective device of the supply circuit.
3. Limited approach boundary (see Table 1): This boundary establishes the distance around energized parts that only a qualified person may enter. If an unqualified person must enter the limited approach space to perform a minor task, like inspection, then a qualified person must advise them of the possible hazards and ensure that the unqualified person is safeguarded.
4. Restricted approach boundary (see Table 1): This boundary establishes the distance around exposed, energized parts that only a qualified person may enter.
5. Prohibited approach boundary (see Table 1): Crossing a prohibited boundary (Table 1) is considered working on exposed, energized conductors or circuit parts. This includes crossing the boundary with hands, feet, other body parts, probes, tools, or test equipment regardless of protective clothing.
6. Qualified person: A person trained in and thoroughly familiar with the construction and operation of equipment and the hazards involved. This person must also be familiar with the proper use of special precautionary techniques for the task to be done, personal protective equipment (PPE), insulation and shielding materials, and insulated tools and test equipment.
1. Training and experience determines whether an employee is considered to be a "qualified person." A person may be considered "qualified" with respect to work on or within the limited approach boundary for certain equipment and "unqualified" with respect to other equipment.
2. Trainees may be considered qualified persons for the performance of certain duties if they meet all of the following:
• Are undergoing on-the-job training
• Have demonstrated ability to perform their duties safely to their level of training
• Are under the direct supervision of a qualified person
7. Troubleshooting and testing: Actions necessary to measure voltage and current and to verify the operability of equipment without repairing or replacing components.