PURPOSE:
To provide safe precautions for the draining and depressur-ing of toxic or combustible materials.
APPLICATION:
All plant and field operations.
POTENTIAL HAZARDS:
• Static Electricity- [See: Electricity]
• Combustible and Toxic Fluids • Environmental Impact PRECAUTIONS:
Draining and Depressuring should be carried out in a controlled fashion. Valves should be opened slowly.
• Depressuring:
Caution should be exercised to ensure that any vessel, line, or piece of equipment to be depressured, has been completely isolated. Depressuring should be done only by qualified personnel. Valves that are blocked in should be tagged. Pressure gauges should not be relied
Draining & Depressuring
on for assurance of complete depressuring. [See: Energy Isolation]
• Draining:
When draining a vessel, certain precautions must be followed:
1. Before draining, the worker must know where the material is going, and the situation at that area (i.e., welding in the vicinity, or if it is a liquid, how it is being contained).
2. Pressured vessels should not be drained through hose. Temporary, secured piping or existing drain lines should be used.
3. When draining, the worker should not leave the area. If it is necessary to leave, he should close the valve.
ELECTRICAL
PURPOSE:
To provide a general understanding of the hazards associ-ated with electricity.
APPLICATION:
All plant and field operations.
POTENTIAL HAZARDS:
Static Electricity:
Sparks resulting from the accumulation of static electricity often cause fires. A static charge can be generated from friction resulting from the passage of oil through a pipeline, the pouring of liquid from one container to another, or steam passing through a hose. Static electricity can also be caused by the flow of air, vapor, steam, water, moving belts of flywheels or rubbing clothing. The hazard is more severe in dry cold weather than in humid weather when most surfaces are coated with a film of moisture, making them
Electrical
good conductors and draining off static charges.
Steam, a blast of sand, or hydrocarbons rushing through hose or pipe, or issuing from open end pipes, can generate a large static charge. The operator should refrain from open-ing sample lines or drains any wider than necessary.
Another source of potential static electricity is the use of portable plastic flammable liquid containers (1 - 5 gallon containers used for removing, filling, storing on a plastic pickup box liner).
PROCEDURES:
Most power tools and portable electrical test equipment are not rated for use in hazardous areas, and are equipped with standard U-ground plugs. It is necessary, in many instances, to use a “short cheater” cord to adapt for explosion-proof electrical receptacles, or extension cords to the non-explo-sion-proof tool or test equipment. Due to the hazards of arcing electrical equipment or connections, the following procedures must be followed:
• All electrical equipment not approved for use in hazardous areas, must be treated as “hot work”, taking the necessary gas checks and obtaining Hot Work Permits - [See: Safe Work Permits]
• All extension cords used must have explosion-proof ends (connectors)
• All “cheater cords” must be less than 2 feet in length with one male explosion-proof end and one female standard U-ground plug, and must be used only at the immediate location of the tool or test equipment
• All connections at standard U-ground plugs must be made and adequately taped (to prevent them from pulling apart), before plugging into the explosion-proof receptacles
• When the job is completed, connections must be
Electrical
broken at the explosion-proof receptacle first • All portable electrical equipment that is approved
for use in hazardous areas (such as some pumps and air movers driven by explosion-proof mo- tors) must have cords equipped with explosion-proof ends. This cord must be rated for extra hard usage as per the Canadian Electrical Code (re: rule 18-122) Where an electrical hazard exists because of dampness (i.e., boilers being cleaned), portable lighting units should be used.
Portable lighting units must have heavy-duty extension cords with ground fault interrupter, or that permitted by local regulations. Suitable guards must be provided for portable lamps
Grounding/Bonding:
The terms “bonding” and “grounding” should not be used interchangeably, because the two processes have distinctly different functions. Bonding eliminates a difference in po-tential between objects, but does not eliminate a difference in potential between these objects and the earth. Ground-ing eliminates a difference in potential between an object and ground. The usual precaution to avoid static electricity sparking is proper bonding and grounding:
• Bonding and grounding are effective only when applied to conductive bodies. Bonding and grounding systems should be inspected regularly for good mechanical condition.
• Before loading or unloading any fluid/material by hose or piping, the truck/equipment must be grounded and bonded.
• When samples are taken in a container, the operator must ensure the container is in contact with the filling nozzle or bonded by cable. When drawing samples in a glass bottle, the filling nozzle must be in contact with the liquid in the bottle.
Electrical
• When Draining or Depressuring fluid/material into a container, the container must be bonded to the drain and depressuring valve.
• All equipment and buildings must be grounded according to the applicable electrical regulations.
Cathodic Protection:
The nature of a cathodic protection system is to put an electrical charge on the pipe or equipment in question, to prevent external corrosion. As a result, the cathodic protec-tion must be shut off or disconnected, and the equipment bonded and grounded before work is started.
Work in the Vicinity of Underground Power Cable:
No person shall commence excavation work until the vicinity has been checked and underground electrical power cables located.
Electrical power cables should be shut-off whenever possible, prior to commencing work. All underground power cables shall be located by hand digging method or Hydrovacing methods.
PRECAUTION:
• Electrical Grounding:
Serious harm can result from electricity with rela-tively low voltages if equipment is not properly grounded.
• Portable Lighting:
Where an electrical hazard exists because of damp-ness (i.e., boilers being cleaned), portable lighting units should be used. Portable lighting units must have heavy-duty extension cords with ground fault interrupter, or that permitted by local regulations.
Suitable guards must be provided for portable lamps.
Electrical
• Batteries:
Batteries used and/or stored in enclosed spaces must be vented to remove hydrogen gases. Sealed, maintenance free batteries are excluded from this requirement.
• Inspection:
Thermography (infra-red scan) is a recommended practice on electrical equipment to locate potential problems. This should be done on a routine basis or before any major shutdowns.
• Identification:
All electrical panels should be identified as to the equipment they control.
Appropriate signs should be posted on electrical switch gear cabinets, sub-stations and rooms to warn personnel of electrical danger.
Danger – An “Equipment Starts Automatically” sign must be displayed on equipment which starts automatically.
Above Ground Clearance:
PRECAUTION:
Minimum clearance from an overhead power line is as follows:
The employer must accurately determine the voltage of any energized electrical equipment or conductor and the mini-mum distance from it required by 19.24 (2) subsection (1).
Safe limit of approach distances from overhead power lines for persons and equipment
Electrical
Alberta - Refer to OH & S sections 225, 226 schedule 4 for further information
British Columbia - Refer to OH & S Table 19-1 for further information
Ontario:
Over 750 V to 150 kV: 3m Over 150 kV to 250 kV: 4.5m Over 250 kV: 6m
These clearances apply to any direction, vertical or hori-zontal. If it is necessary to work closer than the minimum distance, authorization shall be obtained from the utility
Electrical
Operating voltage between conductors of overhead
power line Safe limit of approach distance for persons and equipment
0-750 volts
Insulated or polyethylene covered conductors 300 millimetres
0-750 volts Bare, uninsulated 1.0 meter
Above 750 volts Insulated conductors 1.0 meter
750 volts – 40 kilovolts 3.0 meters
69 kilovolts, 72 kilovolts 3.5 meters
138 kilovolts, 144 kilovolts 4.0 meters
230 kilovolts, 260 kilovolts 5.0 meters
500 kilovolts 7.0 meters
Minimum distance Voltage
Phase to phase Meters Feet
Over 750 V to 75 kV 3 10
Over 75 kV to 250 kV 4.5 15
Over 250 kV to 550 kV 6 20
company. When utility company approval or authorization is required, the operating line voltage must be verified by a designated, competent individual from the utility company.
The area directly under or adjacent to an overhead power line shall not be used for storage of material, or equipment.
No excavations or similar operation shall be carried out in the vicinity of overhead power lines that would reduce the original support of the power line. Earth or other material shall not be placed under or adjacent to an overhead power line in such a manner that the minimum ground clearance would be reduced.
Vehicle load clearance shall not be of a height that would be in violation of the safe limits of approach from overhead power lines.
RESPONSIBILITIES:
Only company-authorized personnel may work on electri-cal equipment.
[See: Electrical Protection Branch Regulations]
TRAINING:
Only the following trained and BP authorized personnel will be allowed to do Electrical work on BP Facilities and Pipelines:
a) Journeyman Electricians b) Electrician Apprentice
c) Refer to the Provincial Electrical regulations.
Only Journeyman Electricians or, Apprentices under the direct supervision of Journeyman Electrician, may work on equipment rated at more than 750 volts.
Any person who knows of a fire of electrical origin or sus-pected electrical origin shall, as soon as practicable, report the accident, contact or fire to a technical Administrator for the electrical discipline or to a safety codes officer and the safety codes officer shall notify a technical
Administra-Electrical
tor for the electrical discipline. After an accident described in subsection (1), no person shall remove or interfere with anything in, on or about the place where the accident oc-curred until permission has been granted by a safety codes officer in the electrical discipline, unless it is necessary to do so to prevent death or injury, to protect property or to restore service. Refer to Safety Codes Act Section 16 (1-3) for further information.