Editing Utility pole (section)

==Pole attachment hardware==
[[File:American telephone practice (1905) (14753288101).jpg|thumb|left|Standard arrangement for telephone poles]]
The primary purpose of pole attachment hardware is to secure the cable and associated aerial plant facilities to poles and to help facilitate necessary plant rearrangements. An aerial plant network requires high-quality reliable hardware to
*Structurally support the distribution cable plant
*Provide directional guying to accommodate lateral stresses created on the pole by pole line configurations and pole loading configuration
*Provide the physical support and protection for drop cable plant from the pole to the customer premises
*Transition cable plant from the aerial network to underground and buried plant
*Provide the means for safe and effective grounding, bonding, and isolation connections for the metallic and dielectric components of the network.
Functional performance requirements common to pole line hardware for utility poles made of wood, steel, concrete, or Fiber-Reinforced Composite (FRC) materials are contained in Telcordia GR-3174, ''Generic Requirements for Hardware Attachments for Utility Poles''.<ref>[http://telecom-info.njdepot.ericsson.net/site-cgi/ido/docs.cgi?ID=SEARCH&DOCUMENT=GR-3174& GR-3174, ''Generic Requirements for Hardware Attachments for Utility Poles'']</ref>

=== Attachment hardware by pole type ===

*'''Wood poles'''
[[File:Palo_SES_Tegna_260513.jpg|thumb|Head of a 400&nbsp;V pole in Switzerland. In Europe, insulators usually were attached directly at the pole.]]
:The traditional wood pole material provides great flexibility during placement of hardware and cable apparatus. Holes are easily drilled to fit the exact hardware needs and requirements. In addition, fasteners such as lags and screws are easily applied to wood structures to support [[outside plant]] (OSP) apparatus.

*'''Non-wood poles'''
:There are three main non-wood pole materials and structures on which the attachment hardware may be mounted: concrete, steel, and fiber-reinforced composite (FRC). Each material has intrinsic characteristics that need to be considered during the design and manufacture of the attachment hardware.

:*'''Concrete poles'''
[[File:Several power pole made of concrete, in Iran 2017 -- چند تیر برق بتنی در ایران.jpg|thumb|Several power poles made of concrete]]

::The most widespread use of concrete poles is in [[Oceanic climate|marine environments]] and coastal zones where excellent corrosion resistance is required to reduce the impact of sea water, salt fog, and corrosive soil conditions (e.g., marsh). Their heavy weight also helps the concrete poles resist the high winds possible in coastal areas.

::The various designs for concrete poles include tapered structures and round poles made of solid concrete; pre-stressed concrete (spun-cast or statically cast); and a hybrid of concrete and steel.

::The drilling of installed concrete poles is not feasible. Users may wish to have the attachment hardware cast into the concrete during the pole manufacture. As a result of these operational difficulties, banded hardware has become the more popular means to attach cable plant to concrete poles.
::Design criteria and requirements for concrete poles can be derived from various industry documents including, but not limited to, ASCE-111, ACI-318, ASTM C935, and ASTM C1089.

:*'''Steel poles'''
[[File:Views of Candaba Viaduct Apalit Bypass Road fields 10.jpg|thumb|Steel poles of Hermosa–Duhat–Balintawak 230,000 volt transmission line along [[Candaba Viaduct]] of [[North Luzon Expressway]] (NLEx) in [[Apalit]], [[Pampanga]].]]
::Steel poles can provide advantages for high-voltage lines, where taller poles are required for enhanced clearances and longer span requirements. Tubular steel poles are typically made from 11-gauge galvanized steel, with thicker 10- or 7-gauge materials used for some taller poles because of their higher strength and rigidity. For tall tower-type structures, 5-gauge materials are used.

::Although steel poles can be drilled on-site with an [[Annular cutter|annular]] drill bit or standard twist drill, it is not a recommended practice. As with concrete poles, bolt holes could be built into the steel pole during manufacture for use as general attachment points or places for steps to be bolted into the pole.

::Welding of attachment hardware or attachment ledges to steel poles may be a feasible alternate approach to help provide reliable attachment points. However, operational and practical hazards of welding in the field may make this process undesirable or uneconomical.

::Steel poles should meet industry specifications such as: TIA/EIA-222-G, ''Structural Standard for Antenna Supporting Structures and Antennas'' (current); TIA/EIA-222; ''Structural Standards for Steel''; and TIA/EIA-RS-222, or an equivalent requirement set to help ensure a robust and good quality pole is being used.

:*'''Fiber-reinforced composite (FRC) poles'''
::FRC poles cover a family of pole materials that combine fiberglass (fiber) strength members with a cross-linked polyester resin and a variety of chemical additives to produce a lightweight, weather-resistant structure. FRC poles are hollow and similar to the tubular steel poles, with a typical wall thickness of {{cvt|1/4|to|1/2|in|mm|0}} with an outer polyurethane coating that is ~{{cvt|0.002|in|mm|2}} thin.

::As with all the other non-wood poles, FRC poles cannot be mounted with the traditional climbing hardware of hooks and gaffs. FRC poles can be pre-drilled by the manufacturer, or holes can be drilled on site. Attachments using lag bolts, teeth, nails, and staples are unacceptable for FRC poles. Through-bolts are used instead of lag bolts for maximum bonding to the pole and to avoid loosening of hardware.

::The relevant industry documents covering FRC poles include: ASTM D4923, ANSI C136.20, OPCS-03-02, and Telcordia GR-3159, ''Generic Requirements for Fiber-Reinforced Composite (FRC), Concrete, and Steel Utility Poles''.<ref>[http://telecom-info.njdepot.ericsson.net/site-cgi/ido/docs.cgi?ID=SEARCH&DOCUMENT=GR-3159& GR-3159, ''Generic Requirements for Fiber-Reinforced Composite (FRC), Concrete, and Steel Utility Poles'']</ref>