Hazardous Locations

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26.1 This section applies to electrical equipment and installations in hazardous locations as defined in the Canadian Electrical Code ( C. E. C. ) Part I, C 22.1-98; every electrical installation in a hazardous location shall comply with either Section 18, or Annex J 18 of Appendix J of the C. E. C. , except as modified in TP 127 Section 26. It is recommended that in all new vessel construction the electrical installations in hazardous locations be in accordance to C. E. C. Section 18 for Class 1, Zone 0, Zone 1 and Zone 2; existing installations which employ the Division system for Class 1 locations shall be permitted continued use of the Division system provided the installations comply with Annex J 18 of Appendix J of C.E.C. It shall be noted from Table 26-1 that equipment permitted in Zone 2 is also permitted for installation in a Class I, Div. 2 location.

26.2 Electrical equipment which is intended to be installed in areas that are classed as hazardous locations shall be certified safe and listed by a certifying authority for the particular atmosphere or location in which the equipment is to be installed; in addition the exposed surface temperature of the electrical equipment shall not operate in excess of the ignition temperature of the explosive atmosphere which may exist in the hazardous area.

26.3 Distribution systems with grounded neutral or grounded phases shall not be used in hazardous locations; distribution systems with hull return shall not be used, but this does not preclude the installation of:

1. impressed current cathodic protective systems;
2. insulation level monitoring devices provided the circulation current does not exceed 30 milliamperes under the most unfavourable conditions.
3. limited and locally grounded systems, such as starting and ignition systems of internal combustion engines, provided that any possible resulting current does not flow directly through the hazardous location.

26.4 The Class I hazardous locations comparison chart between the Zone method of equipment protection and the Division system are found in Table 26-1.

Table 26-1 : Class I Certified Equipment Comparison Chart

Zone System		Division System
Intrinsically safe i or ia	Zone 0
All Equipment acceptable in Zone 0 Flameproof d Pressurized p Increased safety e intrinsically safe ib encapsulation m	Zone 1	Division 1	Class I, Div. 1 Equipment intrinsically safe i, ia
Equipment acceptable for Zone 0 Equipment acceptable for Zone 1 and Class I, Div. 2 Non sparking n	Zone 2	Division 2	Equipment Acceptable for Class I, Div. 1 and Div. II + Flameproof d Pressurized p Intrinsically safe ib Increased safety e Non-sparking n Encapsulation

26.5 Where a subsection states that an electrical system is to be intrinsically safe, the system shall be certified as intrinsically safe for use in a hazardous location;

1. each electric cable for an intrinsically safe system must:
   1. be 50 mm or more from cable of non-intrinsically safe circuits;
   2. be partitioned by a grounded metal barrier from other non intrinsically safe electric cables; or
   3. be a shielded cable;
2. installation instructions and restrictions on the system shall be submitted to the Board for inspection; typical restrictions that must be specified include:
   1. voltage limitations;
   2. allowable cable parameters recommended by the manufacturer;
   3. maximum length of cable recommended by the manufacturer; and
   4. ability of system to accept passive devices.
3. intrinsically safe systems must not be interconnected unless the systems were certified safe with the particular arrangement; and
4. the deck wiring diagram required by section 36 shall specify:
   1. system identification as to manufacturer’s model number;
   2. system use;
   3. cable parameter including length and type of cable;
   4. wiring and equipment locations; and
   5. installation details.

26.6 Purged and pressured equipment shall meet the requirements of CSA Standard CAN/ CSA -E79-2, the National Fire Protection Association No. 496 or IEC Publication 79-2.

26.7 Electrical equipment installations in a Class I, Zone 0 hazardous location shall be in accordance with the following:

1. only electrical equipment certified intrinsically safe “i” or “ia” shall be permitted in a Zone 0 hazardous location; intrinsically safe circuits in accordance with Section 26.2;
2. seals are required where:
   1. rigid conduit leaves a Class I, Zone 0 hazardous location; except that where a conduit passes through a hazardous zone and which no fitting or piece of equipment is installed in the run, a seal is not required provided the run extends 300 mm beyond the bulkhead of the hazardous location and the location is a non hazardous zone; and
   2. at first point of termination of a continuous sheathed cable.
3. cable for use in an intrinsically safe system must meet:
   1. the requirements of section 12 and subsection 26.5 of this section; and
   2. the recommendations of ISA RP 12.6 issued by The Instrument Society of America for “Installation of Intrinsically Safe Instrument Systems in Class I Hazardous Locations”, except Appendix A.1;

26.8 Electrical equipment installation in a Class I, Zone 1, or Division 1 hazardous location shall be in accordance with Section 26.2 and as providing one or more of the protective methods listed in Table 26-1 for a Zone 1 area:

1. cable for Class I Zone 1 hazardous location must:
   1. be braided armoured marine cable constructed in accordance with section 12 of this standard or MI type cable; or
   2. be unarmoured marine cable installed in threaded rigid metal conduit; or
   3. RW90 Cross-linked polyethylene or ethylene propylene rubber insulated cable rated -40°C installed in threaded rigid metal conduit.
2. flexible cords and cables must be C.S.A. certified for extra hard usage;
3. wiring methods shall be of threaded metal rigid conduit and fittings or cables approved for Class I hazardous locations, with associated seals or cable glands that comply with subsection 26.2.

26.9 Electrical equipment installation in a Class I, Zone 2, or Division 2 hazardous location shall be in accordance with Section 26.2 and as providing one or more of the protective methods listed in Table 26-1 for a Zone 2 area:

1. cable installed in a Class I, Zone 2, or Division 2 shall be approved marine cable protected from mechanical damage or in accordance with subsection 26.8 (a) (iii).
2. wiring methods shall be of threaded rigid metal conduit or cables approved for hazardous locations, with associated seals or cable glands that comply with subsection 26.2.

26.10 Electrical equipment installation in a Class II and III hazardous locations shall be certified safe in accordance with Section 26.2:

1. cable for Class II and III shall be in accordance with subsection 26.9 (a); and meet the requirements of section 12;
2. wiring methods shall be of threaded rigid metal conduit or marine cables;
3. sealing shall be of cable glands certified safe in accordance with section 26.2.

26.11 Switches shall be certified safe for hazardous locations and each switch controlling electrical equipment in hazardous locations must have a pole for each circuit conductor.

26.12 Fans located in a hazardous location shall be so designed as to render sparking impossible in the event of the impeller tips touching the fan casing.

26.13 Each electric motor for a fan that ventilates a hazardous location must be certified safe for the same class, zone, division and group, as the ventilated location, or be:

1. outside the ventilation duct;
2. 3 m from the ventilation duct termination; and
3. in a non-hazardous location.

26.14 Equipment mounted in a ventilation duct that ventilates a hazardous location shall meet the classification requirements of that space.

26.15 Each pulley drive in a hazardous location must have:

1. a conductive belt, i.e. anti-static; and
2. pulleys, shafts and driving equipment grounded to meet the National Fire Protection Association, No. 77.

26.16 Each vessel that carries combustible liquid cargo with a closed-cup flashpoint of 60 degrees C , or higher must have:

1. electrical equipment located in cargo tanks certified safe for a Class I, Zone 0 location; and
2. no storage battery in any cargo handling room.

26.17 Each vessel that carries combustible or flammable cargo with a closed-cup flashpoint lower than 60 degrees C or liquid sulphur cargo, or a tankship that carries inorganic acid cargo shall meet the requirements of this subsection except:

1. a vessel carrying bulk liquefied flammable gases as a cargo, cargo residue or vapour must meet the requirements of subsection 26.18;
2. a vessel carrying carbon disulphide must have only Zone 0 electric equipment in the locations listed in paragraphs (f) through (m) of this subsection;
3. electric cable must be as close as practicable to the centerline and must be away from cargo tank openings;
4. an enclosed hazardous location that has certified safe lighting fixtures must:
   1. have at least two lighting branch circuits;
   2. be arranged so that there is light for re-lamping any de-energized lighting circuits; and
   3. not have the switch within the space for those spaces containing lighting fixtures under paragraphs (h), (j) and (k) of this subsection.
5. if a submerged cargo pump motor is in a cargo tank:
   1. low liquid level, motor current or pump discharge pressure must automatically shutdown power to the motor if the pump loses suction;
   2. an audible and visual alarm located at the cargo control station must be actuated by the shutdown of the motor; and
   3. there must be a lockable circuit breaker or lockable switch that disconnects power to the motor;
6. a cargo tank must not contain any electric equipment except:
   1. electrical equipment certified safe for a Class I, Zone 0 location; and
   2. submerged cargo pumps, and
   3. supply cable for submerged cargo pumps;
7. a cargo handling room must not have any electric cable or other electric equipment, except:
   1. electrical equipment certified safe for a Class I, Zone ,1 and Class 1, Division 1 location; and
   2. only cables in which are supplying the necessary operational equipment permitted in item g (i);
8. lighting for cargo handling room except a cargo handling room under paragraph (i) of this subsection, must be lighted through fixed-glass lenses in the bulkhead or overhead; each fixed-glass lens must be wire-inserted glass that is at least 6 mm thick and arranged to maintain the watertight and gastight integrity of the structure; the fixed-glass lens may form a part of a lighting fixture if the following are met:
   1. there is no access to the interior of the fixture from the cargo handling room;
   2. the fixture is vented to a non-hazardous location;
   3. the fixture is wired from outside the cargo handling room; and
   4. the temperature on the cargo handling room surface of the glass lens, based on an ambient temperature of 40 degrees C , is not higher than 180 degrees C .
9. a cargo handling room which precludes the lighting arrangement of paragraph (h) of this subsection, or where the lighting arrangement of paragraph (h) of this subsection does not give the required light, must have certified safe electrical equipment in accordance with item g (i);
10. an enclosed space that is immediately above, below or next to a cargo tank must not contain any electric equipment except equipment allowed for cargo handling rooms in paragraphs (g) and (h), and
    1. through runs of cable in accordance with subsection 26.8; and
    2. watertight enclosures with bolted and gasketed covers containing only:
       1. depth sounding devices;
       2. log devices; and
       3. impressed-current cathodic protection system electrodes;
11. a cargo hose stowage space must not have any electric equipment except as noted in items g (i) (ii) and through runs of cable in accordance with subsection 26.8; and
12. a space that has cargo piping must not have any electrical equipment except equipment in accordance with items g (i) (ii) and through runs of cable in accordance with subsection 26.8; and
13. a location in the weather except on a tank vessel carrying inorganic acid must have equipment in accordance with items g (i) (ii) and through runs of cable in accordance with subsection 26.8;
    1. within 3 m of:
       1. A cargo tank ullage opening;
       2. A cargo pipe flange;
       3. A cargo valve;
       4. A cargo handling room entrance;
       5. A cargo handling room ventilation opening; or
       6. A spill cargo containment save-all for loading or unloading;
    2. within 5 m of cargo tank pressure/vacuum valves and a vertical zone of unlimited height;
    3. within 10 m of cargo tank vent outlets and a vertical zone of unlimited height;
    4. on the open deck over the cargo area to the full width of the vessel, plus 3 m fore and aft on the open deck, up to a height of 2.4 m above the deck.
14. except for those spaces listed in paragraphs (f) through (i), a space that has a direct opening to any space listed in paragraphs (f) through (m) must have electric equipment and installations certified safe as the hazardous location to which it opens.
15. distribution systems, except intrinsically safe circuits, feeding or passing through a hazardous location referred to in this sub-section shall have a device capable of continuously monitoring the insulation level to ground and giving an audible alarm at a manned position when ground current exceeds 30 milliamperes.
     
    
     
    
16. Any semi-enclosed space that contains a condition described in item (m), must only have electrical equipment certified safe for Class I, Zone 2, or Division II fitted outside the limits described in (m).
17. Equipment in enclosed spaces, other than Category A machinery spaces, having access from open deck areas in item (m) need not be of a certified safe type provided the access is through a double door air lock. Arrangements for an air lock should include:
    1. two gas tight steel doors of self-closing type with no hold back arrangement spaced at least 1.5 m , but not more than 2.5 m apart.
    2. The non-hazardous space and the air lock are to be maintained at overpressure relative to the external hazardous area by independent mechanical ventilation systems arranged such that a single failure will not result in the simultaneous loss of overpressure in both the non-hazardous space and the air lock.
    3. failure of either ventilation system described in item (ii) must be alarmed at a normally manned control station.
    4. Notices, warning that the doors are to be kept closed must be fitted.
    5. Following shutdown of the ventilation systems described in (ii), all electrical equipment in the space that is not certified safe, must remain de-energized until the space is determined to be gas free or has been sufficiently purged to assure the space is gas free, and the ventilation overpressure restored, prior to energization of this equipment.

26.18 Each vessel that carries bulk liquefied flammable gases or ammonia as a cargo, cargo residue or vapour must meet the requirements of this subsection:

1. as used in this subsection:
   1. the terms “gas-safe” and “gas-dangerous” spaces are found in the Interpretation section of this standard
   2. the term “gas-dangerous” does not include the weather deck of an ammonia carrier;
2. each submerged cargo pump motor installation must be inspected by the Board:
3. electrical equipment, must not be installed in a gas-dangerous space or zone, except:
   1. intrinsically safe “i” and “ia” electrical equipment and wiring, and
   2. other equipment as allowed in this subsection;
4. a submerged cargo pump motor, if installed in a tank, must meet the following requirements:
   1. low liquid level, motor current or pump discharge pressure must automatically shut down power to the pump motor if the pump loses suction;
   2. there must be an audible and visual alarm at the cargo-control station that activates if the motor shuts down under the requirements of subparagraph (i) of this paragraph; and
   3. there must be a lockable circuit breaker or lockable switch that disconnects the power to the motor;
5. electrical equipment must not be installed in a hold space that has a tank that is not required to have a secondary barrier except:
   1. through runs of cable in accordance with subsection 26.8; and
   2. lighting fixtures suitable for a Class 1, Zone 1, or Div. 1 location;
   3. depth sounding devices in gastight enclosures;
   4. log devices in gastight enclosures;
   5. impressed current cathodic protection system electrodes in gastight enclosures; and
   6. braided armoured marine cable or MI type cable for a submerged cargo pump motor;
6. electrical equipment must not be installed in a space that is separated by a gastight steel boundary from a hold space that has a tank that must have a secondary barrier except:
   1. through runs of cable in accordance with subsection 26.8; and
   2. lighting fixtures suitable for a Class 1, Zone 1, or Div. 1 location;
   3. depth sounding devices in gastight enclosures;
   4. log devices in gastight enclosures;
   5. impressed current cathodic protection system electrodes in gastight enclosures;
   6. braided armoured marine cable or MI type cable for submerged cargo pump motor;
7. a cargo-handling room must not have any electrical equipment installed other than equipment or lighting fixtures certified safe for the location in accordance with Section 26.17 (g) (i);
8. a space for cargo hose storage or a space that has cargo piping must not have any installed electrical equipment, except:
   1. lighting fixtures in accordance with Section 26.17 (g) (i);
   2. through runs of cable in accordance with subsection 26.8;
9. a gas-dangerous zone on the open deck must not have any installed electrical equipment, except:
   1. certified safe electrical equipment suitable for a Class 1, Zone 1, or Div. 1 location that is necessary for the operation of vessel;
   2. through runs of cable in accordance with subsection 26.8;
10. a space, except those named in paragraphs (e) through (h) of this subsection that has a direct opening to gas-dangerous spaces or zones must have no electrical equipment except as allowed in the gas-dangerous space or zone;
11. each gas-dangerous space that has lighting fixtures must have at least two branch circuits for lighting;
12. each switch and each overcurrent protective device for any lighting circuit that is in a gas-dangerous space must open all conductors of the circuit simultaneously;
13. each switch and each overcurrent protective device for lighting in a gas-dangerous space must be in a gas-safe space; and
14. distribution systems, except intrinsically safe “i” and “ia” circuits, feeding or passing through a hazardous location referred to in this subsection shall have a device capable of continuously monitoring the insulation level to ground and giving an audible alarm at a manned position when ground current exceeds 30 milliamperes.

26.19 If the voltage of a distribution system on a tank vessel is 1000 volts or more, line to line, and the distribution system is grounded, any resulting current must not flow through hazardous location. Distribution systems on tank vessels of less than 1000 volts, line to line, shall not be grounded subject to Section 26.3.

26.20 Vessels which may carry coal

26.20.1 Electrical cables and equipment installed in cargo holds shall be limited to that which is necessary for the operational activities during loading, transporting and unloading the coal cargo. The electrical equipment necessary to be installed in the cargo hold shall be certified safe for a Class II, Div. 1, Group F location and the equipment in these spaces shall be electrically isolated while the space is not open to the atmosphere for ventilation.

26.20.1 Electrical cables and equipment installed in cargo holds shall be limited to that which is necessary for the operational activities during loading, transporting and unloading the coal cargo. The electrical equipment necessary to be installed in these areas shall be certified safe for Class II, Div. 1, Group F locations and means provided for positive isolation of the electrical equipment located in these spaces.

26.20.2 In the unloading tunnels, cargo transfer areas and adjacent spaces of self-unloaders the electrical equipment shall be certified safe for not less than a Class II, Div. 2, Group F locations which are to be continuously ventilated by mechanical means. The spaces shall be regularly monitored for the presence of methane gas; an audible and visual alarm shall be provided at the main machinery control station to indicate any failure of the tunnel and adjacent spaces ventilation system and a means provided to isolate the Class II Division 2 equipment in the event of ventilation failure.

26.20.3 Electrical equipment located in the tunnel and adjacent spaces necessary in the event of an emergency shall be certified safe for a Class I, Zone 2, Group II A, or Class I, Division 2, Group D locations.

26.20.4 The hazardous locations on the open deck shall extend in a 3 meter radius around the ventilation outlets of the tunnel and adjacent spaces.

26.20.5 Where necessary, electrical cables installed in cargo holds or bins shall be in accordance with section 26.5 or 26.9 (a); those cables located in the unloading tunnels, cargo transfer areas or adjacent spaces may be unarmoured marine cable constructed in accordance with section 12 which shall be suitably protected against mechanical damage; cables seals, terminations or glands shall be applicable to the hazardous requirements in accordance with section 26.2.

26.20.6 Electrical equipment certificated for Class I locations may exceed those temperatures permitted for installation in a Class II location, therefore care should be taken to ensure that Class I equipment is also certificated for Class II locations.

 

 

 

26.21 Each electrical installation where a flammable anaesthetic is used or stored shall meet the requirements of the Canadian Electrical Code, Part I, Section 24.

26.22 Passenger ships with special category spaces:

1. in special category spaces above the bulkhead deck electrical equipment and wiring shall be installed at least 45 cm above the uppermost deck within the space unless the electrical equipment and wiring are necessary below this level for the safe operation of the ship, in which case the electrical equipment and wiring shall be a type certified safe for Class I, Division 2, Group D, or Zone 2, Group II A locations; electrical equipment installed at more than 45 cm above the deck shall be of a type so enclosed and protected as to prevent the escape of sparks; the reference to a level of 45 cm above the uppermost deck means that the hazardous area extends from 45 cm above the uppermost fixed or portable deck to the deck below; electrical equipment and wiring, if installed in an exhaust ventilation duct, shall be of a type certified safe for Class I, Division 2, Group D, or Zone 2, Group II A hazardous locations;
2. in special category spaces below the bulkhead deck and in cargo spaces containing motor vehicles with fuel in their tanks for their own propulsion, electrical equipment and wiring shall be certified safe for Class I, Division 2, Group D; electrical equipment and wiring, if installed in an exhaust ventilation duct, shall be of a type certified safe for Class I, Division 2, Group D, or Zone 2, Group II A hazardous locations; and
3. loss of ventilation in any special category space shall actuate an audible and visual alarm on the bridge or at a position that will always be manned while vehicles with fuel in their tanks are onboard.

26.23 Closed Ro-Ro spaces in cargo vessels carrying motor vehicles with fuel in their tanks for their own propulsion shall comply with the following provisions:

1. except as provided in 26.22 (b) electrical equipment and wiring shall be of a type suitable for use in a Class 1, Division 2, Group D, or Zone 2, Group II A hazardous location;
2. above a height of 450 mm from the deck and from each platform for vehicles, if fitted, except platforms with openings of sufficient size permitting penetration of gasoline vapours downwards, electrical equipment of a type so enclosed and protected as to prevent the escape of sparks shall be permitted as an alternative on condition that the ventilating system is so designed and operated as to provide continuous ventilation of the cargo spaces at the rate of at least ten air changes per hour whenever vehicles are on board;
3. other equipment which may constitute a source of ignition of flammable vapours shall not be permitted;
4. electrical equipment and wiring in the exhaust ventilation duct shall be of a type certified safe for use in a Class 1, Division 2, Group D, or Zone 2, Group II A hazardous location and the outlet from any exhaust duct shall be sited in a safe position, having regard to other possible source of ignition; and
5. scuppers shall not be led to machinery or other spaces where sources of ignition may be present.

26.24 The electrical installation in battery compartments shall comply with Section 19; electrical equipment installed in battery compartments where vented batteries are employed shall be certified safe for a Class I, Division 1, Group B location, or a method of protection equal to Zone 1, Group IIC (refer to subsection 26.1); compartments where sealed batteries (valve regulated) are used, exclusively the electrical equipment shall be in accordance with Section 19.5.10.

26.25 A space for the stowage or mixing or paint shall not have any electric equipment, except:

1. electric equipment certified safe for a Class I, Division 1, Group D location or, equipment provided with a method of protection equal to Zone 1, Group IIA; and
2. through runs of armoured marine cable or MI type cable.

26.26 Distribution systems supplying essential services or emergency power shall be so arranged to avoid hazardous locations where practicable.

26.27 Helicopter hangar electrical equipment installations are to comply with TP -4414 “Guidelines Respecting Helicopter Facilities on Ships”.

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