The wood pole is a relatively basic, yet robust and useful, structural resource, dating back to antiquity in usage and maintaining significance today as it numbers 100 million in the United States. Despite the objective simplicity of the common natural material, guidance for defining the quality, dimensions, and basic engineering data of preserved wood poles has been in use for the past century, undergoing refinement throughout the years to assure reliable performance of contemporary utility poles. ANSI O5.1-2017 – Wood Poles – Specifications and Dimensions, is the result of this process.
ANSI O5.1-2017 provides minimum specifications for the quality and dimension of wood poles that will ultimately be used as single-pole utility structures. The poles described in the standard are to be, as stated in the standard, “simple cantilever members subject to transverse methods only”.
ANSI O5.1-2017 covers the species, length, and class of the wood poles to be used by electric and other communications utilities, as well as their associated strength values, the types of treatment (such as seasoning and steam conditioning details), and aids to penetration (such as incising, groundline boring, or kerfing).
Furthermore, ANSI O5.1-2017 addresses prohibited, permitted, and limited defects, such as cross breaks, sap stains that are not accompanied softening or other decay, and bark inclusions less than 2 inches in depth, respectively. Manufacturing requirements, including bark removal, sawing, trimming, shaving, and marking, are also designated in the standard.
Beyond this, there is a great deal of definitions and material requirements covered within the ANSI O5.1-2017 document. If the specifications of this standard are modified in any way, such as when meeting special considerations, complete detailed instructions should be given to the supplier.
ANSI O5.1-2017 was developed by the Accredited Standards Committee O5 (ASC O5) and published by the American Wood Protection Association (AWPA). AWPA is a non-profit organization that promulgates voluntary standards for technologies which protect wood from degradation. The development of its standards is advanced through the involvement of producers of preservatives, producers of treated and untreated wood products, end users, engineers, architects, building code officials, and others during the consensus process of the organization’s technical committees.
ASC O5 is accredited by ANSI, which it maintains jointly with AWPA as its current Secretariat. Committee O5 traces its origins back to 1924, when it was organized by the Bell Telephone System and the U.S. Independent Telephone Association’s American Standards Associations (ASA) Telephone Group. Today, the Committee develops standards for utility poles, crossarms, and wood bracing used by electric and communications utilities, like ANSI O5.1-2017.
Other standards for utility poles developed by ASC O5 include:
ANSI O5.2-2020 – Structural Glued Laminated Timber for Utility Structures
ANSI O5.3-2015 – Solid Sawn Wood Crossarms and Braces – Specifications and Dimensions
ANSI O5.4-2017 – Naturally Durable Hardwood Poles – Specifications and Dimensions
ANSI O5.5-2010 (R2016) – Wood Ground Wire Moulding – Specifications and Dimensions
ANSI O5.6-2010 – Solid Sawn-Naturally Durable Hardwood Crossarms & Braces – Specifications & Dimensions
These standards can be acquired together as the ANSI O5. – Wood Poles Package.
ANSI O5.1-2017 – Wood Poles – Specifications and Dimensions is available on the ANSI Webstore.