CHAPTER 131
ELECTRICITY ACT

[SUBSIDIARY LEGISLATION]

INDEX TO SUBSIDIARY LEGISLATION

   NOTICES

      The Establishment of Licensing Board Notice

   ORDERS

      The Electricity (Delegation of Powers) Order

      The Electricity (Variation to the Supply of Electricity) Order

   RULES

      The Electricity Rules

      The Electricity (Places of Public Entertainment) Rules

      The Electricity (Meter Rental) Rules

NOTICES

THE ESTABLISHMENT OF LICENSING BOARD NOTICE

(Section 9)

G.N. No. 264 of 1967

   A Licensing Board consisting of the following persons has been established–

   The Assistant Director (Electrical and Mechanical), Ministry of Communications, Power and Works.

   The Manager (Northern Area), The Tanzania Electric Supply Co., Ltd.

   The Manager (Southern Area), The Tanzania Electric Supply Co., Ltd.

ORDERS

THE ELECTRICITY (DELEGATION OF POWERS) ORDER

G.Ns. Nos.
322 of 1943
27 of 1945
274 of 1950
41 of 1951
457 of 1957

   1. This Order may be cited as the Electricity (Delegation of Powers) Order.

   2. A Board to be styled the Electricity Board and constituted in the manner prescribed in paragraph 3 of this Order is hereby deputed to exercise and perform on behalf of the President the powers and duties specified in the schedule hereto, which powers and duties the President is empowered to exercise and perform by the Electricity Act *.

   3. (1) The Electricity Board shall consist of the following members that is to say–

   The Minister for Communications and Works
The Director of Public Works
The Land Officer.

   (2) When the substantive Land Officer is absent from Tanzania, the Director of Lands and Surveys shall serve in his place as a member of the Board.

   (3) The Minister for Communications and Works shall be Chairman of the Board, and, if he be absent from any meeting of the Board, the officer next named in the list of members specified in subparagraph (1) of this paragraph who is then present shall act as Chairman at such meeting.

   (4) The Board shall be duly constituted if there be present at any meeting a quorum of three members.

   (5) All orders, notices or other documents made or issued by the Board shall be signed by the Chairman or other member of the Board acting on his behalf, and any such order, notice or other document so signed shall be deemed to be duly made or issued by the Board.

SCHEDULE
POWERS AND DUTIES VESTED IN THE MINISTER BY THE ELECTRICITY ACT WHICH ARE DELEGATED TO THE ELECTRICITY BOARD

Section of Act

Nature of powers and duties

10(2)(b)

To direct inquiry by an electric inspector.

11

To require the carrying out of distribution work and to approve plans.

12

To approve plans and drawings.

15

To require the supply of energy to public lamps and to give notice of such requirement.

21

To sanction conditions regulating the licensee's relations with consumers and to cancel such conditions.

34

To sanction earth connections and to make orders of the kind prescribed in subsection (2).

35

To receive notice which is required to be given under subsection (1) and to give direction and make appointments of the kind prescribed in subsection (2).

41

To determine plans and to require the licensee to make works for the purposes specified in the section.

43

To require the licensee to do the things specified in the section.

48

To give consent to the use of temporary aerial lines for a period exceeding six weeks.

56

To hear appeals against reports of electrical inspectors and to inquire into and decide upon the matter of such appeals.

57

To approve the method of charging for energy supplied to consumers.

THE ELECTRICITY (VARIATION TO THE SUPPLY OF ELECTRICITY) ORDER

(Section 67)

G.N. No. 83 of 1966

   The Authority to Generate Electricity dated the December, 1958 granted to Williamson Diamonds Limited by the then Governor under section 67 of the Electricity Ordinance now incorporated in the Electricity Act * as section 72 is hereby varied as follows–

   1. The maximum supply of electricity which the Grantee may generate and transmit for own use shall be 12000 kW instead of 8000 kW.

   2. In addition to the Authority granted to the Grantee to generate and transmit electrical energy for its own use the Grantee shall have authority–

   (a)   to supply and sell such energy to the New Alamasi, 1963 Limited at the Alamasi Mine, Shinyanga, and to charge for the said energy at a rate not exceeding the cost of generation; and

   (b)   to supply and sell such to TANESCO, Secondary School and persons resident on the Rights of Occupancy shown in the First Schedule and to charge for the said at a rate not exceeding the cost of production, and the authority granted to supply and sell such to the former Alamasi Limited shall be deemed to have expired.

   3. In lieu of the land office titles set out in the First Schedule there shall be substituted the following land office numbers–

   20864, 26470, 17554, 25332 and 19392.

   4. In lieu of the plants and works set out in the Second Schedule there shall be substituted–

   "7 diesel-operated generating sets-voltage 3.3 k.v. capacity: 900 kW per set;

   2 diesel-operated generating sets-voltage 3.3 k.v. capacity: 3,000 kW per set

together with ancillary, transmission and distribution lines."

   5. The Fourth Schedule shall cease to have affect.

RULES

THE ELECTRICITY RULES

(Section 84)

G.Ns. Nos.
103 of 1932
205 of 1937
107 of 1938
73 of 1942
324 of 1943
17 of 1945
80 of 1947
64 of 1954
60 of 1960
156 of 1990
9 of 1999

1.   Citation

   These Rules may be cited as the Electricity Rules.

2.   Interpretation

   In these Rules, unless the context otherwise requires–

   "conductor" means any wire or cable used for the transmission of electricity;

   "consumer's wire" means any electric line on the consumer's premises which is electrically connected with the licensee's distribution mains by means of a service line;

   "Electricity Board" means the Board constituted under, the provisions of the Electricity (Delegation of Powers) Order *;

   "Managing Director" includes the Regional Director appointed under the Tanzania Telephone Company Limited;

   "pressure" means the difference of electric potential measured in volts between any two conductors, or between any part of either conductor and the earth, as read by a hot wire or electrostatic voltmeter and, is said to be–

   (a)   "extra high" when under ordinary working conditions, it exceeds 6,600 volts;

   (b)   "high" when under ordinary working conditions, it exceeds 650 volts but does not exceed 6,600 volts at the point at which supply is delivered;

   (c)   "medium" when under ordinary working conditions, it exceeds 250 volts but does not exceed 650 volts at the point at which supply is delivered;

   (d)   "low" when under ordinary working conditions it exceeds 30 volts in the case of alternating current and 100 volts in the case of direct current, but does not exceed 250 volts in either case, at the point at which the supply is delivered;

   (e)   "extra low" when under ordinary working conditions, it does not exceed 30 volts in the case of alternating current and 100 volts in the case of direct current at the point at which supply is delivered;

   "sub-station" means any building, structure or enclosure either above or below ground, and containing, transforming or converting apparatus for the supply of electricity.

3.   Duties of Electricity Board

   (1) The Electricity Board shall be responsible for the administration of these Rules.

   (2) The Electricity Board may from time to time give general or specific instructions to the licensing board, licensing officers and electric inspectors as to the performance of their duties and may direct any questions of doubt and difficulty to be referred to it for decision.

4.   Frequency and systems of supply

   (1) The frequency of alternating current systems shall be 50 complete cycles per second.

   (2) The supply of electricity shall be given on one or more of the following systems–

   (a)   two wire system at a nominal pressure of 230 volts measured at the consumer's terminals–

      (i)   direct current;

      (ii)   single-phase alternating current;

   (b)   three-wire systems at a nominal pressure of 440 volts between the outer conductors and 220 volts between each outer and intermediate conductor, measured at the consumer's terminals–

      (i)   direct current;

      (ii)   single-phase alternating current;

   (c)   three-phase four-wire systems, at a nominal pressure of 400 volts between phases and 230 volts between each phase and neutral conductor, measured at the consumer's terminals;

   (d)   high or extra high pressure alternating single-phase two-wire supply to motors, motor generators, pole transformers, transformers placed in street boxes or in substations, together with a supply from the pole transformers or substations to a low pressure system or systems as defined in paragraphs (a) and (b) of this rule;

   (e)   high or extra high pressure alternating current three-phase supply to motors, motor generators, rotary convertors, pole transformers, or transformers placed in substations, together with a supply from the pole transformers or substations to a low pressure system or systems as defined in paragraphs (a), (b) and (c) of this rule;

   (f)   high or extra high pressure, two-wire direct current supply to motors and motor generators;

   (g)   series street lighting for any pressure not exceeding 3,300 volts;

   (h)   such other systems as may be authorised by the Electricity Board.

5.   Voltage of supply

   (1) For purposes of domestic supply not exceeding 3 kilowatts the nominal pressure shall not exceed 230 volts at the consumer's terminals and for domestic supply exceeding 3 kilowatts the nominal pressure shall not exceed 440 volts at the terminals of a direct current or single-phase alternating current system and 400 volts at the terminals of a three-phase system.

   (2) Supply of power for industrial purposes may be given at any voltage provided that the transforming station is so enclosed as to be inaccessible except to authorised persons.

   (3) Supply for series street lighting may be given for pressures up to but not exceeding 3,300 volts.

6.   Regulation of pressure and frequency

   (1) The pressure shall be maintained within 5 percent above or below the nominal pressure at the consumer's terminals.

   (2) Any consumer who has reason to suspect that the variation in voltage exceeds the limits specified may make a formal complaint to the electric inspector who shall if he deems it necessary after investigation, cause the licensee to connect a portable recording voltmeter, to be provided and maintained by the licensee, to record the pressure between the service lines.

   (3) Where the variations recorded exceed the specified limits, the licensee shall take immediate steps to comply with this regulation.

   (4) The frequency shall be maintained within two and a half percent above or below the standard of 50 cycles per second.

   (5) A meter referred to in the Act or in these Rules shall be deemed to be "correct" when its limits of error as certified by an electric inspector do not exceed those laid down in the "British Standard Specification" for electricity meters and when it cannot register at no load and, any meter, maximum demand indicator or other apparatus for which there is for the time being no "British Standard Specification", shall be deemed to be "correct" when its limit of error, as certified by an electric inspector, does not exceed three percent above or below absolute accuracy at all loads in excess of one-tenth of full load and up to full load and when it cannot register at no load.

7.   Location of overhead lines

   (1) One side of every street shall be left free by the licensee for telegraph lines.

   (2) Except with the permission of the Electricity Board, or subject to an agreement between the Postmaster-General and the licensee, all overhead electric lines shall be placed on the opposite side of the street to that on which any telegraph lines exist and where the erection of the overhead electric lines necessitates an alteration of any existing telegraph lines and such alteration is approved by the Postmaster-General, the expense of the alteration shall be borne by the licensee:

   Provided that where existing telegraph lines occupy both sides of a street at the same place, the Postmaster-General shall bear the cost of putting all telegraph lines on the one side of the street, or consent to an arrangement for the joint use of poles on both sides of the street.

   (3) In running the electric lines along a street where no telegraph line exists the licensee shall keep to one side of the street, and in running electric service lines to the opposite side of the street, such lines shall be erected in accordance with the provisions of rule 42.

8.   Facility for service connections

   Where distributing mains are on one side of the street and telegraph lines are on the other, and service is required to be given from either to the other, the licensee and the Postmaster-General shall give to each other reasonable facilities as far as possible to effect supply and where possible, the licensee's service lines shall pass over telegraph lines, and telegraph service lines shall pass under electric lines.

9.   Notice of completion

   The licensee shall, prior to the completion of the whole or of any separate portion fo the work to which the licensee refers, give to the Director of Public Works at least one month's notice in writing of the estimated date of each completion and the licensee shall not use the works or any portion of the works thereof until the Director of Public Works has given notice in writing that he has received from the electric inspector a certificate that such works or such portion of the works have been satisfactorily carried out.

10.   Extensions

   (1) Before commencing the extension or alteration of any line already erected, other than a service line the licensee shall give at least seven days' notice in writing to the Director of Public Works of intention to carry out the work and, in the case of an extension such notices shall be accompanied by a plan showing location, size, number and pressure of wires and cables proposed to be extended including the height of the poles, if any, with calculations of the stresses and sag in the longest span of each line.

   (2) Notwithstanding the provisions of rule 9, the licensee may use such extensions and service lines, provided that the work has been carried out in strict conformity with the requirements of these rules; and for the purpose of ascertaining whether or not the extensions and service lines comply with such conditions the electric inspector may from time to time inspect the work and, if the electric inspector finds that any portion of the work does not comply with the requirements of these rules the Director of Public Works call upon the licensee to discontinue the use of such part of the work until the rules are complied with.

   (3) The maps and plans required under section 13 of the Act shall be brought up to date within twenty-eight days of the completion of any extension, shall show the date of erection of each electric line and be available at any time for examination by the electric inspector.

   (4) Within twenty-eight days after the end of each month the licensee shall furnish to the Director of Public Works a list of all service lines erected or altered during the previous month, and on the 31st March of each year shall furnish to the Director of Public Works a summarised list of all extensions to the mains made during the previous twelve months, giving the date, location or route and the lengths of the mains.

11.   Connection of circuits with earth

   The connection of circuits with earth shall be made in accordance with the following conditions–

   (a)   the intermediate conductor of a low or medium pressure three-wire single-phase system and the neutral conductor of a low or medium pressure three-phase four-wire system shall be effectively earthed at the point of supply, that is, at the generating station, sub-station or transformer and at such other points along the electric distribution line as are necessary to give a resistance not exceeding 10 ohms between any point in such conductor and the general mass of earth;

   (b)   in a three-wire direct current system, the intermediate conduct shall be earthed at the generating station only and the current from the intermediate conductor to earth shall be continuously recorded by means of a recording ammeter and, if at any time the current exceeds one-thousandth part of the maximum supply current, steps shall be immediately taken to improve the insulation of the system;

   (c)   in high and extra high pressure three-phase star-connected systems the neutral point may be earthed at the point of supply and at the neutral point of each star-connected transformer in the circuit or alternatively if the neutral conductor is not earthed or if the system be delta-connected, the approved means shall be provided in each circuit for indicating faulty insulation in any part of the circuit and if the insulation of any circuit is faulty, immediate steps shall be taken to make good the insulation before being placed in service;

   (d)   in the case of a star-connected system of any voltage the neutral conductor of which is connected to earth, the resistance between that conductor and earth shall be sufficiently low to ensure that the fuse or automatic circuit breaker or trip coil in any phase shall disconnect the circuit from the source of supply in the event of an accidental earth occurring on that phase or, in the case of high pressure or extra high pressure lines, upon accidental contact with a low or medium pressure line and in the case of automatic circuit breakers, each phase must be equipped with a trip coil;

   (e)   where any part of a circuit is normally connected with earth, no switch, fuse or circuit breaker shall be inserted in the earthed conductor or in any conductor connected to an earthed conductor thereto, and the connection with earth shall be efficiently maintained, except when it is interrupted by means of a link for the purpose of periodical tests.

12.   Earth connections to water mains

   Subject to the provisions of rule 37, earth connections may be made to the water supply pipes in townships where a public main supply of water is conveyed in underground pipes and where the system of electricity supply is of alternating current, subject to the following conditions–

   (a)   an earth wire connecting an electrical installation to a water main or water pipe is to be used only–

      (i)   as a measure of safety for the purpose of returning to the source of supply, such leakage current as may flow, or result from a failure of insulation;

      (ii)   for radio frequency currents and currency from radio interference suppression devices;

   (b)   a water main or water pipe shall not be cut, drilled or broken, for purposes of paragraph (a) and, all reasonable and proper care shall be exercised in making any earth connection, to prevent injury or damage to a water main or water pipe;

   (c)   every earth connecting device to a water main or water pipe, shall be of such an approved design as to ensure an efficient electrical connection and, other than as provided for in paragraph (d) shall be attached in a position convenient for and ease of access;

   (d)   an earth connection to a buried water main or water pipe shall only be made after notice to the water supply authority concerned;

   (e)   where an earth connection is made to a water main or water pipe or any premises in which a water-meter is installed, a proper, sufficient and suitable bond shall in all cases be placed across such water-meter by the user of the meter is installed, free of expense to the water supply authority;

   (f)   where the water supply authority has reason to believe that damage to water mains or water pipes is being caused by an excessive flow of current from an earth connection made to a water pipe or water main the water supply authority shall in general, request the licensee to test the installation, in the presence of a representative of the water supply authority and if for any reason the water supply authority should desire to test for electrical leakage from an installation to water mains or water pipes, the water supply authority may make such test after advising the licensee of the intention, giving such notice to any consumer as may be necessary and in the presence of a representative of the licensee.

13.   Testing earth connections

   (1) A test shall be made by the licensee every twelve months, to ensure that all earth wires used in connection with electric lines other than the neutral conductor of a three-phase four-wire system with multiple earth connection or a continuous earth wire with multiple earth connection are intact and the earth connections are effective:

   Provided that–

   (a)   tests required under rule 14(3) must be made at least three times per annum;

   (b)   all earths on guards erected over or under telegraph wires shall be tested every twelve months, and copies of tests forwarded to the Director of Public Works;

   (c)   between the electric supply-line or electrical apparatus or other devices to be earthed and the general mass of earth the electrical resistance of each separate earth connection shall not exceed 10 ohms and shall be as much less than 10 ohms as is required to ensure at all times and immediate and safe discharge to earth of electrical.

   (2) Records shall be kept of all tests made.

14.   Switchboards in power houses and substations

   (1) All power house and sub-station switchboards, including the frames to which they are attached, shall be made of fireproof material and the maximum permissible current and temperature in any conductor mounted on or leading to such switchboard shall not exceed the values permitted under the rules made from time to time by the Institute of Electrical Engineers of Great Britain.

   (2) No conductor at a pressure above 650 volts shall be exposed on the front of any switchboard and the back of any switchboard with conductors at a pressure of 150 volts and over or above, shall be screened and made inaccessible except to authorised persons.

   (3) All power house and sub-station switchboards controlling high pressure and extra high pressure circuits, shall be provided with two efficient and independent earth connections, connected in parallel, to which all frames, instrument cases and other non-current carrying metal parts shall be connected and means shall be provided for testing the resistance between these two connections through the earth, such tests being made at least three times per annum and to be recorded.

   (4) Every power house and sub-station switch intended to be used for breaking a circuit and every circuit breaker, shall be so constructed or arranged that it cannot with proper care be left in partial contact or accidentally fall or move into contact when left out of contact and all enclosed switches shall have an external attachment to indicate clearly whether the switch is open or closed.

   (5) All power house and sub-station switchboard circuits shall be so arranged that the course of any main conductor may be readily identified.

   (6) Passage ways around power house or sub-station switchboards other than those of a totally enclosed type shall be such as to provide the clearance specified as follows–

   (a)   low or medium pressure switchboards; an overhead clearance of at least seven feet from the floor to any bare conductor, and a passage way with at least the feet and three inches horizontal clearance from either front or back of the switchboard or any bare conductor affixed to the switchboard;

   (b)   high pressure and extra high pressure switchboards other than operating desks or panels working solely at low pressure, an overhead clearance of not less than eight feet from the floor to any bare conductor and a passage way with a horizontal width of not less than three feet and six inches from either front or back of the switchboard and all conductors must be so screened or guarded that they cannot be touched accidentally and the prescribed passage way at the back of the board must be measured from this screening.

15.   Safety appliances in power stations and substations

   (1) Fire buckets of suitable capacity, filled with clean dry sand and ready for immediate use in extinguishing fire or suitable fire extinguishers filled with a non-conducting fluid, shall be kept in a convenient place adjacent to the electrical apparatus.

   (2) Rubber gloves, mats, rubber soled boots, galoshes and insulated platforms or stools shall be provided for use when necessary.

   (3) A notice containing directions in English, Gujerati and Kiswahili as to resuscitation of persons suffering from the effects of electric shock shall be exhibited in a conspicuous place.

16.   Circuit breakers

   (1) All outgoing feeders and distributors from any power station or sub-station shall be provided with fuses or inverse time limit automatic circuit breakers, set to open within three seconds at a current not exceeding one hundred percent over the normal rated load of such feeder or distributor:

   Provided that in transformer substations of fifty kilowatt capacity or less only the high pressure or primary side of the transformer need be fused, and special precautions shall be taken in the adjustment of such high pressure fuses to the capacity of the transformer.

   (2) Where a circuit breaker is used it shall be located in accessible position and shall be of the loose handle type and capable of breaking the overload referred to in subsection (1) current by hand, without undue formation of an arc and with no risk of injury to the operator.

   (3) Automatic trip coils shall be provided on each phase of star-connected systems with earthed neutral.

17.   Fuses

   Every fuse shall be either of such construction or so protected by a switch that the fusible metal may be readily renewed without danger.

18.   Minimum size of conductor

   The diameter of any conductor in any low or medium pressure electric supply-line laid or erected for the supply of electricity shall be not less than 0.104 inch except as provided in paragraph (e) of rule 28, for high or extra high pressure supply line, the diameter shall not be less than 0.128 inch.

19.   Material and qualify of overhead line conductors

   (1) Overhead electric supply-line conductors, shall be of copper, aluminium, mild steel or iron or, of a combination of aluminium conductors with a steel core or, of any other material or combination of materials, as may be approved by the Director of Public Works.

   (2) All overhead electric supply-line conductors at the time of erection, shall comply as regards elongation, ultimate strength and elasticity, with the specifications of the British Engineering Standards Association in force in the material time.

20.   Stresses in overhead line conductors

   (1) The stresses in overhead electric supply-line conductors, shall not exceed the limits specified under this rule, when subject to the forces resulting from the weight of the conductor combined with a wind pressure of 9lb per square foot of diametral plane if situated within and, 12lb per square foot if situated outside, municipal or township areas coincident with a temperature of 500F or such other temperature as may be specified in the licence.

   (2) The limiting stress shall be 27,000lb per square inch for hard drawn copper conductors, 13,000lb per square inch for aluminium conductors calculated upon the area of the equivalent solid conductor. The limiting stress for a composite steel aluminium conductor shall be 30,000lb per square inch for a seven strand cable, 27,000lb per square inch for a 37 strand cable calculated upon the combined areas of the steel and aluminium. The limiting stress for mild steel cable shall be 34,000lb per square inch and for iron conductors 22,500lb per square inch. Where other materials are used the limiting stress under the conditions specified above shall be one-half the ultimate breaking stress of the wire or cable whether composite or non-composite.

21.   Clearances

   (1) Overhead electric supply-lines at low or medium pressure shall not in any part thereof be at a less height than 18 feet from the ground except as provided in rule 42 and that the height may be reduced to 15 feet over ground which is entirely inaccessible to vehicular traffic.

   (2) Overhead electric supply-lines at high pressure shall not in any part thereof be at a less height than 18 feet from the ground and 20 feet from the ground in municipal or township areas and the minimum height of an earthed wire or of a neutral conductor or three-phase four-wire system shall conform to the conditions of paragraph (1).

   (3) Overhead electric supply-lines at extra high pressure up to 66,000 volts between phases shall not in any part thereof be at a less height than 20 feet from the ground and electric supply-lines at 66,000 volts and over shall have a minimum clearance of 22 feet.

   (4) Where low or medium and high pressure or low or medium and extra high pressure electric supply-lines are carried on the same poles, a minimum height of 18 feet below the low or medium pressure lines shall be provided to allow telegraph crossings to pass underneath and when such electric supply-lines are erected along tramway routes the low or medium pressure lines shall be at such height as to permit the telegraph circuits that cross the street to pass above the trolley wire and below the low or medium pressure lines.

   (5) Overhead electric supply-lines crossing electric tramway lines shall have a minimum clearance of four feet above the trolley wire.

   (6) Overhead electric supply lines shall not come within 2 feet of any other aerial lines or cables, except at a pore and then only by arrangement between the respective owners of the wires.

   (7) Overhead electric supply-lines shall be so erected as to be inaccessible to any person either from the ground or from any building or structure whether permanent or temporary without the use of a ladder or other special appliance.

   (8)(a) If, at any time subsequent to the erection of an electric supply-line, any person proposes to erect a new building or structure, whether permanent or temporary, or to make in or upon any building or structure any permanent or temporary addition or alteration, he shall, if such building, structure, addition or alteration would render the aerial line accessible otherwise than by the aid of a ladder or other special appliance, give notice in writing of his intention to the licensee or owner, as the case may be, and to the electric inspector and shall furnish therewith a scale drawing showing the proposed building, structure, addition or alteration and the scaffolding required during its construction, and shall not commence work upon the building, structure, addition or alteration until the electric inspector has certified that neither during nor after the execution of the work will the electric supply-line be so accessible.

   (b) On receipt of such notice the licensee or owner, as the case may be, shall, without undue delay, so alter the electric supply-line as to ensure that it will not be accessible in such a manner as to contravene the provisions of subrule (7), either during or after the execution of the work, and may recover the reasonable cost of such alteration from the person from whom the notice was received:

   Provided that the licensee or owner as the case may be, may, before so altering the electric supply-line, require the person from whom the notice was received to deposit the estimated cost of such alteration:

   Provided further that an electric inspector, may, if he is satisfied that the electric supply-line has been so guarded as to secure the protection of persons and property from injury or risk of injury, permit the work to be executed prior to, or, in the case of a temporary addition or alteration, without the alteration of the electric supply-line.

   (9) The maximum sag shall be computed on the assumption that the conductor is subjected to a temperature of 140ºF or to such temperature as may be specified in the licence.

   (10) Where necessary for a linesman to climb between live conductors of separate circuits on the same pole the following minimum climbing spaces shall be provided between conductors–

   (a)   low or medium pressure covered wires 36 inches;

   (b)   low or medium pressure bare wires 42 inches;

   (c)   high pressure covered wires 42 inches;

   (d)   high pressure bare wires 48 inches.

   (11) Where overhead wires cross navigable waterways, special clearance shall be provided as directed by the Electricity Board.

   (12) If the Electric Inspector shall be of the opinion that as a result of a failure to comply with the provisions of subrule (8) a danger to the public or to any person exists, then he may direct by notice in writing that the person erecting such new building or structure or making such addition or alteration to a building or structure shall immediately upon receipt of such direction discontinue or cause to be discontinued work on the building or structure until the Electric Inspector advises in writing that work may be resumed:

   Provided that any person may within seven days of the receipt by him of such a direction and, provided that he shall have complied with it, appeal to a court presided over by a Resident Magistrate who shall have power, if he considers that a danger does not exist to the public or any person, to revoke the said direction.

22.   Support for overhead line

   (1) Every support for overhead electric supply-lines shall be so located as to avoid unduly obstructing pedestrian or vehicular traffic.

   (2) Every support for overhead electric supply-lines shall be of durable material, and of sufficient strength to withstand forces due to wind pressure, change of direction of line, and unequal length of span and the factor of safety of each support shall be two in the case of iron, steel or ferroconcrete, and four in the case of wood, calculated on the crippling load of the structure. In computing the applied moments, a wind pressure of 20lb. per square foot of diametrical plane surface and 12lb. per square foot of diametrical plane of a cylindrical surface shall be assumed and where high or extra high pressure lines cross a road approved earthing bars shall be erected at each side of such road crossing:

   Provided that the Electricity Board may, after considering the advice of the Electrical Engineer, permit a variation of the requirements imposed by this subrule to such extent as the said Board may specify in any particular case.

   (3) The conductors shall be attached to suitable insulators carried on cross arms or brackets of suitable material and cross section in a manner approved by an electric inspector duly appointed under section 10.

   Guard hooks erected at angles shall be effectively earthed and where electric lines are covered with insulating material they shall be so attached to the insulators that their insulation shall not be impaired thereby, and no joint in an insulated conductor shall be made within four feet of an insulator and pins for pole top insulators shall not be screwed into the pole top, but attached to the side of the pole.

   (4) At terminal poles or pull-offs the cross arm shall always be fixed on the opposite side of the pole to the pull-off.

   (5) Overhead electric distributing mains at low or medium pressure may be carried on brackets attached to buildings, provided they are inaccessible from any portion of the building without the use of a ladder or other special appliance or that they are so screened as to prevent the possibility of accidental contact by any person, and provided also that they are secured in such a manner that they cannot fall away from the insulator support or make contact with the building.

   (6) Where guys or stays are used they shall be securely anchored and earthen.

   (7) Each pole shall be clearly and permanently marked with a number.

23.   Earthing of poles and ironwork

   (1) Metal cross arms on wooden or concrete poles shall be earthed either at each pole or by means of a continuous earth wire carried from pole to pole and earthed at intervals of not more than five spans.

   (2) Iron or steel poles shall be effectively earthen.

24.   Quality of galvanized iron, etc.

   Galvanized iron wire used for stays, cradles or other mechanical purposes; galvanized iron binding wire; arm bolts, nuts and washers; stay swivels, truss and brace rods and truss tie and brace bolts; stay rod tighteners and test pieces shall conform with the British Standard Specifications for each material so far as those specifications are applicable.

25.   Maximum length of span

   (1) The distance between supports carrying electric supply-lines within Municipal or Township areas, or within such other limits as may be specified in the licence, shall, notwithstanding the provisions of rules 20 and 28 hereof, not exceed 180 feet.

   (2) The distance between supports carrying electric supply-lines outside such limits shall be determined by the provisions of rules 20, 21 and 28(e).

26.   Angle of crossing thorough-fares

   Where an overhead electric supply-lines is transferred from one side of a street to the other the angle formed by the original alignment and the portion of the line crossing the street shall approximate be as closely as practicable to a right angle, and shall not exceed 135 degrees and the crossing span shall be as short as possible.

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