ANSI ASC O5 O5.4:2017 pdf download.Naturally Durable Hardwood Poles:Specifications and Dimensions.
ANSI ASC O5 O5.4 provides minimum specifications for the quality and dimensions of naturally durable hardwood poles without preservative treatment to be used in single-pole utility structures. The poles described herein are considered as simple cantilever members subject to transverse loads only. Fiber strength values, provided as a basis for determining pole class sizes, apply only to poles that meet or exceed the minimum quality specifications. The pole class size tables for each fiber strength value for the naturally durable hardwood species represent their heartwood circumferences unless the sapwood also possesses high natural durability. These fiber strengths may be used to estimate the average groundline moment capacity of the naturally durable hardwood poles.
Only poles that meet the naturally durable hardwood species criteria established in this Standard will be allowed to be listed as an approved naturally durable hardwood pole.
1.2 Natural durability
The heartwood of all naturally durable hardwood poles listed in this Standard shall be tested in accordance with ASTM D2017 – 05 and have an Indicated Class of Resistance of “Highly Resistant” for all applicable test fungi. The sapwood shall have an indicated Class of Resistance of “resistant” or higher according to ASTM D2017-05. Sapwood does not need to be rated as “Highly Resistant”, and if it is not, pole dimensions are based on heartwood measurements alone1. Sapwood tested and rated as “Highly Resistant” will be included in the determination of pole dimensions as described in section 4 of this Standard.
NOTE: This Standard does not purport to establish the durability or Indicated Class Resistance of any particular species listed herein. The users of this Standard shall review all pertinent data and make their own determination as to the appropriateness of the natural durability of a particular species for the user’s application.
1.3 Moisture content (MC)
The natural durable hardwoods must have reached 20% MC or less at the heartwood/sapwood boundary, measured with a moisture meter before shipping. This requirement is intended to eliminate or reduce the potential splits caused by severe drying. Also, the pole classes in this Standard are determined in the dry state (< 20% MC) (see Dimension Tables below). 1.4 Shrinkage The naturally durable hardwoods dimension presented in this Standard have been adjusted to accommodate for permanent shrinkage of the naturally durable hardwood poles. The shrinkage amount will vary somewhat from species to species. For the purposes of this Standard, 5% shrinkage is used in deriving the required pole dimensions. 1.5 General requirements All naturally durable hardwoods shall originate from managed forests with sustainable forest management practices and shall be certified by an agency or third party acceptable to the end user as a sustainably managed forest. Examples of such certifying organizations include; Sustainable Forestry Initiative® (SFI), Forest Stewardship Council® (FSC); Sistema Brazileiro de Certificação Florestal (CERFLOR); as well as others.ANSI ASC O5 O5.4 pdf download.