JUNE 26.] THE NEW ZEALAND GAZETTE. 1987

safety of such supports, if of iron, steel, or ferro-con-
crete, taking into consideration all possible stresses,
including wind-pressure at 30 lb. per square foot on
plane surfaces and 18 lb. per square foot of dia-
metrical plane for cylindrical surfaces, shall be such
that the moment resulting from these stresses shall
not exceed one-half the applied moment which will
cripple the supporting structure. The factor of
safety of the support, if of wood, shall be four,
reckoned upon the ultimate strength of the material.

25. Along the transmission-wire route a wire or wires of
    hard-drawn copper not smaller than No. 12 standard wire
    gauge may be run for service telephone purposes. This wire
    shall be bound throughout to double-shed porcelain insulators.

26. At the generating and transformer stations the trans-
    mission-wires shall be securely and safely led in ; and pro-
    tection against lightning shall be provided at each end of the
    lines. The telephone wire or wires shall be suitably guarded
    against lightning, shall be fused, and such arrangements shall
    be made where the telephone is placed as will prevent the
    possibility of injury resulting to any person using the tele-
    phone should a power-wire come into contact with the tele-
    phone wire.

27. Where conductors cross telegraph or telephone lines
    they shall be insulated and protected by the licensee to the
    satisfaction of the Minister of Telegraphs.

28. The transmission-line shall be on the opposite side of
    the road or street to that on which the telegraph and tele-
    phone lines are run, and where there are no telegraph or
    telephone wires the licensee shall erect his lines on one side
    of the road or street only. It shall be patrolled throughout
    its whole length at least once a week, and its insulation shall
    be so maintained that the maximum leakage shall not exceed
    one-thousandth part of the maximum supply current. Suit-
    able means shall be provided for indicating leakage on the
    line. Every leakage shall be remedied without delay. Tests
    shall be made weekly, and recorded by the licensee.

29. Transformers shall have easily removable fuses for the
    primary circuit, and shall, as far as possible, be installed in
    small enclosures accessible only to the licensee’s officers or
    servants. Transformers for use outside shall be fitted with
    watertight cast-iron cases, and shall be affixed to poles so as
    to be inaccessible except by the use of a ladder or other
    special appliance. Every transformer shall have its iron case
    effectively connected with earth.

30. Conductors used for making the lightning-guard and
    transformer-case earth connections shall be of copper, and
    shall have an area of at least 0·023 square inches. They
    shall be properly stapled or fastened to the supports, and
    shall be protected by a batten for a distance of 8 ft. from the
    ground. They shall be run as straight as possible, and be
    properly connected to an earth-plate. A test shall be made
    every three months, and oftener if required, of all earths, to
    ensure that the earth-wire is intact and that the earth is
    effective.

31. Where poles are carrying low-tension wires, the spans
    shall not exceed 200 ft. where the direction of the line is
    straight, or 150 ft. where the direction is curved or where
    the wires make a horizontal angle at the point of support.

32. Low-tension distribution shall be carried out on the
    single-phase system at a pressure of 230 to 250 volts. The
    supply to street lamps, incandescent lamps, and to private
    consumers shall be at a pressure of 230 volts.

Where cables are led to and from transformer enclosures
they shall be protected on the poles by being run in iron pipe,
which shall be effectively earthed.

Low-tension wires or cables shall be covered with a triple
braiding impregnated with waterproof compound, except
where otherwise provided for.

33. Where the erection of the electric lines or wires necessi-
    tates the alteration of existing telegraph or telephone lines or
    wires, the expense of such alteration shall be borne by the
    licensee.

34. The sectional area of the conductor in any electric line
    for distribution purposes laid or erected in any street shall
    not be less than the area of a No. 10 S.W.G. wire.

35. All material used for insulating electric lines or appa-
    ratus shall be of the best quality, and thoroughly durable
    and efficient, having regard to the conditions of its use. Suit-
    able provision shall be made where necessary for the protec-
    tion of the insulating material against injury or removal. If
    the protection so provided is wholly or partly metallic it
    shall be efficiently connected with earth.

36. Any metallic body to be “efficiently connected with
    earth” shall be connected with the general mass of the earth
    in such manner as will ensure at all times an immediate and
    safe discharge of electrical energy.

37. Every support for an aerial line for distribution pur-
    poses shall be properly stayed against forces due to wind-
    pressure, change of direction of the line, or unequal lengths
    of span. The factor of safety shall be for all aerial lines and

for all other parts of the structure at least 6, and for aerial
wires at least 4, taking the maximum possible wind-pressure
at 30 lb. per square foot.

38. The low-tension wires shall be attached to double-shed
    porcelain insulators carried on cross-arms of suitable material
    and cross-section, and they shall be so attached to the insu-
    lators or guarded that they cannot fall away from the support.

39. Any aerial wire used for low-tension distribution or for
    telephone service shall not in any part thereof be at a less
    height from the ground than 18 ft., or within 5 ft. measured
    horizontally or vertically from any building or erection other
    than a support for the line, except where brought in to a
    building for the purpose of supply.

40. Service lines from aerial lines shall be led as directly
    as possible to insulators firmly attached to some portion of
    the consumer’s premises which is not accessible to any person
    without the use of a ladder or other special appliance. Every
    portion of any service line which is outside a building but is
    within 7 ft. from any part of the building shall be rubber-
    insulated.

41. Where an aerial wire crosses a street, the angle between
    the line and the direction of the street at the place of crossing
    shall not be less than 60°, and the spans shall be as short as
    possible.

42. Where an aerial line crosses or is in proximity to any
    metallic substance, precautions shall be taken by the licensee
    against the possibility of the line coming into contact with
    the metallic substance by breakage or otherwise.

43. Where telegraph or telephone wires are crossed either
    over or under by the low-pressure electric-light wires, there
    shall be a distance of at least 2 ft. between the telephone and
    the electric-light wires, and the former shall, if deemed neces-
    sary, be insulated throughout the whole length of the span
    intersected, and when the crossing is at a telegraph or tele-
    phone pole the spans on each side of the pole shall be
    insulated by the licensee, if required by the Minister of
    Telegraphs. The low-pressure wires shall, where deemed
    necessary, be rubber-insulated at such crossings either over
    the whole span or over such portion of it as will ensure that
    uninsulated portions of the telegraph or telephone and of the
    low-tension electric-light wires shall not come into contact
    with each other. In cases where it may be deemed not
    necessary to insulate both classes of wires, either the tele-
    graph and telephone or the electric-light wires shall be insu-
    lated as may be considered most suitable by the Minister of
    Telegraphs. Where it may be required to cross through
    telegraph or telephone wires with low-tension distribution-
    wires, the latter shall be affixed to porcelain insulators
    mounted on iron brackets suitably attached to the arms
    on each side of the line being passed through, and then
    taken through bell-mouthed iron pipes secured to the arms.
    The iron pipe and brackets shall be efficiently earthed. The
    low-pressure wires shall be insulated with vulcanized rubber
    of 600-megohms-per-mile grade, and the insulation shall ex-
    tend as is indicated in the preceding part of this clause.
    The cost of insulating the telegraph and telephone wires
    shall be borne by the licensee.

Due notice in writing shall be given to the Telegraph
Engineer of the district or his deputy of all works involving
the crossing or intersection of telegraph or telephone wires.

No attempt shall be made to utilize telegraph or telephone
poles as supports for low tension wires until the consent of
the Telegraph Engineer of the district or his deputy shall
first have been obtained, and such applications shall be con-
fined strictly to those cases where no other practicable means
of overcoming the difficulty are available.

44. Efficient guard-wires or other suitable protection shall,
    if required by the Minister of Telegraphs, be erected in a
    manner to meet with the approval of the said Minister at
    all crossings and places where either transmission or distri-
    bution electric-lighting wires intersect telegraph or telephone
    wires. The licensee shall bear the expense of such guard-
    wires or other protective devices in all cases where an
    electric-lighting wire intersects a telegraph or telephone wire
    previously existing.

45. Every aerial line, including its supports, its conductors,
    and their insulating covering, and all the structural parts and
    electrical appliances and devices belonging to or connected
    with the line shall be duly and efficiently supervised and
    maintained by the licensee as regards both electrical and
    mechanical conditions.

46. An aerial line shall be removed so soon as it has ceased
    to be used for the transmission of electricity, unless the
    licensee intends within a reasonable time again to take it
    into use.

47. All metal pipes or coverings containing any electric line
    or wire shall be efficiently connected with earth, and shall be
    so jointed as to make good electrical connection throughout
    their whole length.

48. The licensee shall be responsible for all electric lines,
    fitting, and apparatus belonging to him, or under his control