1、 ANSI O5.1-2017 Wood Poles: Specifications and Dimensions AMERICAN NATIONAL STANDARD FOR WOOD UTILITY PRODUCTS Accredited Standards Committee O5 was first organized in 1924 by the Bell Telephone System and the U.S. Independent Telephone Associations American Standards Association (ASA) Telephone Gro
2、up. The Exchange Carrier Standards Association (ECSA), which later became the Alliance for Telecommunications Industry Solutions (ATIS), accepted sponsorship and Secretariat responsibility for ASC O5 in 1985. The American Wood Protection Association (AWPA) then assumed the role of Secretariat, effec
3、tive January 1, 2011. ASC O5 is jointly accredited with its Secretariat by the American National Standards Institute. This committee develops standards for wood poles, crossarms, braces, and glue laminated timber for utility structures. For more information, visit the ASC O5 website at www.asco5.org
4、. Founded in 1904, the American Wood Protection Association (AWPA) is a non-profit organization that promulgates voluntary standards for technologies which protect wood from degradation. AWPA Standards are developed by its technical committees in an open, consensus-based process that involves indivi
5、duals from all facets of wood preservation: Producers of preservatives and preservative components; producers of treated and untreated wood products; end users of treated wood; engineers, architects and building code officials; government entities, academia, and other groups with a general interest
6、in wood preservation. AWPAs Standards are universally specified for wood protection in the USA, and are recognized worldwide. For more information visit the AWPA website at . AMERICAN NATIONAL STANDARD Approval of an American National Standard requires review by ANSI that the requirements for due pr
7、ocess, consensus, and other criteria for approval have been met by the standards developer. Consensus is established when, in the judgment of the ANSI Board of Standards Review, substantial agreement has been reached by directly and materially affected interests. Substantial agreement means much mor
8、e than a simple majority, but not necessarily unanimity. Consensus requires that all views and objections be considered, and that a concerted effort be made towards their resolution. The use of American National Standards is completely voluntary; their existence does not in any respect preclude anyo
9、ne, whether he has approved the standards or not, from manufacturing, marketing, purchasing, or using products, processes, or procedures not conforming to the standards. The American National Standards Institute does not develop standards and will in no circumstances give an interpretation of any Am
10、erican National Standard. Moreover, no person shall have the right or authority to issue an interpretation of an American National Standard in the name of the American National Standards Institute. Requests for interpretations should be addressed to the secretariat or sponsor whose name appears on t
11、he title page of this standard. CAUTION NOTICE: This American National Standard may be revised or withdrawn at any time. The procedures of the American National Standards Institute require that action be taken periodically to reaffirm, revise, or withdraw this standard. Purchasers of American Nation
12、al Standards may receive current information on all standards by calling or writing the American National Standards Institute. Notice of Disclaimer the type of treatment (including seasoning details, if seasoning is desired); aids to penetration such as incising, groundline boring, or kerfing; and c
13、omplete details for roofing, gaining, boring, and branding not included in this standard shall be given in purchase orders. Complete detailed instructions shall be given to the supplier whenever the requirements of this standard are modified to meet special conditions. 2 Normative references The sta
14、ndards listed below contain provisions which, through reference in this text, constitute provisions of this American National Standard. At the time of publication, the editions indicated were valid. All standards are subject to revision; therefore users of this standard are encouraged to investigate
15、 the possibility of applying the most recent editions of the standards. ASC C2-2007, National electrical safety code.1AWPA Standard M6-07, Brands used on forest products.2ASTM D9-05, Standard terminology relating to wood.3Wood Preservation Statistics, Forest Service, U.S. Department of Agriculture,
16、1973.43 Definitions The following definitions shall apply to the terms used in this standard. Photographs depicting many of these terms may be found in Technical Report O5-TR-01, the Photographic Manual of Wood Pole Characteristics, which is based on this Standard. - 1Available from www.ieee.org 2Av
17、ailable from 3Available from www.astm.org 4Available from the U.S. Government Printing Office, Washington, DC 20402. ANSI O5.1-2017 - 2 - 3.1 air dried: Dried by exposure to air in a yard or shed, without artificial heat. 3.2 air seasoning: Drying by the use of ambient air either in the open or und
18、er cover. 3.3 Boulton drying: Drying by heating in nonaqueous solution under vacuum. 3.4 check: The lengthwise separation of the wood that usually extends across the rings of annual growth and commonly results from stresses set up in wood during seasoning. 3.5 compression wood: Abnormal wood formed
19、on the lower side of branches and inclined trunks of softwood trees. Compression wood is identified by its relatively wide annual rings, usually eccentric; relatively large amount of summerwood/latewood, sometimes more than 50% of the width of the annual rings in which it occurs; and its lack of dem
20、arcation between springwood and summerwood/latewood in the same annual rings. Compression wood, compared with normal wood, shrinks excessively lengthwise. 3.6 cone hole: A hole formed by the stalk of a pine cone during the radial growth of the main stem of several species of pine, principally Radiat
21、a. In Radiata pine, cone holes are typically less than 1/2 inch (13mm) in diameter, exist in the crown of the tree, and extend from the surface of the pole to the pith. 3.7 cross break: A separation of the wood cells across the grain. Such breaks may be due to internal strains resulting from unequal
22、 longitudinal shrinkage or to external forces. 3.8 dead streak: An area, devoid of bark, resulting from progressive destruction of the growth cells of wood and bark at the edges of the streak. On a pole, a dead streak is characterized by a discolored weathered appearance and by lack of evidence of o
23、vergrowth along the edges of the deadened surface. 3.9 decay: The decomposition of wood substance by fungi. 3.10 decay, advanced (or typical): The latter stage of decay in which the destruction is readily recognized because the wood may be punky, soft and spongy, stringy, pitted, crumbly, or is in a
24、 soggy condition. Decided discoloration or bleaching of the rotted wood is often apparent. 3.11 decay, incipient: The early stage of decay that has not proceeded far enough to soften or otherwise perceptibly impair the hardness of the wood. Although the wood is invaded and some of its properties may
25、 have deteriorated, no visible change has occurred, with perhaps the exception of minor discoloration. Incipient decay can occur in living trees. 3.12 decayed knot: A knot containing decay. Two types of decayed knot are recognized: Type I: Knots containing soft or loose fibers (decay) that may exten
26、d the full length of the knot into the pole and that are associated with heart rot; Type II: Knots containing soft or loose fibers (decay) that are not associated with heart rot. 3.13 Earlywood: The portion of the growth ring that is formed during the early part of the growing season. It is usually
27、less dense and weaker mechanically than latewood. 3.14 face of pole: The concave side of greatest curvature in poles with sweep in one plane and one direction, or the side of greatest curvature between groundline and top in poles having reverse or double sweep. 3.15 groundline section: That portion
28、of a pole between 1 foot (30cm) above and 2 feet (61cm) below the groundline, as defined in the pole dimension Tables (see Tables 3 through 10, or Tables 3M through 10M). 3.16 hollow heart: A void in the heartwood caused by decay or insect attack. 3.17 hollow pith center: A small hole at the pith ce
29、nter of the trunk or of a knot caused by disintegration of the pith (small soft core occurring in the structural center of a tree or branch). 3.18 insect damage: Damage resulting from the boring into the pole by insects or insect larvae. Scoring or channeling of the pole surface is not classed as in
30、sect damage. 3.19 kiln dried: Dried in a kiln with the use of artificial heat. 3.20 kiln drying: Drying by the use of artificially heated air in a chamber designed to control temperature, relative humidity, and air flow. ANSI O5.1-2017 - 3 - 3.21 knot cluster: Two or more knots grouped together as a
31、 unit, the fibers of the wood being deflected around the entire unit; distinct from a group of single knots in which each is a unit. A knot cluster shall be considered as a single knot. 3.22 knot diameter: The diameter of a knot on the surface of the pole measured in a direction at right angles to t
32、he lengthwise axis of the pole. The sapwood as well as the heartwood portion of a knot shall be included in the measurement. NOTE For a description of means for defining the limits of knots, see ASTM D9. 3.23 latewood: The portion of the growth ring that is formed after the earlywood formation has c
33、eased. It is usually denser and stronger mechanically than earlywood. 3.24 red heart: A condition caused by a fungus, Fomes pini, which occurs in the living tree. It is characterized in the early stages of infection by a reddish or brownish color in the heartwood. This is known as “firm red heart.”
34、Later the wood of the living tree disintegrates (decays) in small, usually distinct, areas that develop into white lined pockets. 3.25 sap stain: A discoloration of the sapwood, caused by the action of certain molds and fungi, which is not accompanied by softening or other disintegration of the wood
35、. 3.26 scar: A depression in the surface of the pole resulting from a wound where healing has not reestablished the normal cross section of the pole. 3.27 scar, turpentine acid face: An area in the lower portion of a southern pine pole where bark hack removal with acid applied has caused resin to fl
36、ow. No removal of sapwood has occurred. 3.28 scar, turpentine cat face: A depression in the surface of a southern pine pole resulting from a wood hack into the sapwood, where healing has not reestablished the normal cross section of the pole. 3.29 seasoning: Removing moisture from green wood to impr
37、ove serviceability. 3.30 shake: A separation along the grain, the greater part of which occurs between the rings of annual growth. 3.31 shelling: Ring separation extending to the surface of round or sawn timber normally following the growth rings and often associated with limiting defects such as kn
38、ots, compression wood or shake. Ring separation usually becomes more pronounced as the product dries and may be further aggravated by stress developed during horizontal lifting or loading. 3.32 short crook: A localized deviation from straightness that, within any section 5 feet (1.5m) or less in len
39、gth, is more than 1/2 the mean diameter of the crooked section. (See Figure 1, Diagram 3.) 3.33 spiral-grained (twist-grained) wood: Wood in which the fibers take a spiral course about the trunk of a tree instead of a vertical course. The spiral may extend in a right-handed or left-handed direction
40、around the tree trunk. Spiral grain is a form of cross grain. 3.34 split: A lengthwise separation of the wood extending completely through the piece from one surface to another. 3.35 springwood: (See earlywood.) 3.36 steam conditioning: Subjecting poles to steam prior to treatment in a closed vessel
41、. 3.37 sweep: Deviation of a pole from straightness. (See Figure 1, Diagrams 1 and 2.) 3.38 summerwood: (See latewood.) 3.39 through-boring: A process applied prior to preservative treatment whereby holes 0.5 inches (12.5 mm) or less in diameter are drilled through a pole at a slight angle in a patt
42、ern designed to improve preservative treatment. This process is normally only used on Douglas-fir poles in the groundline zone, but the through-bored zone may be extended downwards to the butt or applied near the pole top. ANSI O5.1-2017 - 4 - 4 Pole classes Poles meeting the requirements of this st
43、andard are grouped in the classes identified in Tables 3 through 10 (or Tables 3M through 10M), based on their circumference measured 6 feet (1.8m) from the butt, after bark removal and/or shaving. Poles of a given class and length are designed to have approximately the same load-carrying capacity,
44、regardless of species. Annex B provides further information. 5 Material requirements 5.1 General 5.1.1 Species 2. Decay, except as permitted for firm red heart in 5.3.1, defective butts in 5.4.4, and decayed knots in 5.4.6; 3. Dead streaks, except as permitted in 5.4.3; 4. Holes, open or plugged, ar
45、e prohibited, except for those deliberately placed holes for explicit use as increment boring holes, framing holes, or through-boring holes. All increment boring holes should be plugged with treated wood plugs; 5. Hollow butts or tops, except as permitted under hollow pith centers and defective butt
46、s; 6. Marine borer damage; and 7. Nails, spikes, and other metal not specifically authorized by the purchaser. 5.3 Permitted defects 5.3.1 Firm red heart Firm red heart not accompanied by softening or other disintegration (decay) of the wood is permitted. 5.3.2 Hollow pith centers Hollow pith center
47、s in the tops or butts and in knots are permitted in poles that are to be given full-length treatment. 5.3.3 Sap stain Sap stain that is not accompanied by softening or other disintegration (decay) of the wood is permitted. 5.3.4 Scars Turpentine acid face scars are permitted anywhere on the pole su
48、rface. 5.4 Limited defects 5.4.1 Bark inclusions Depressions containing bark inclusions shall be not more than 2 inches (5cm) in depth, measured from the surface of the pole. 5.4.2 Compression wood The outer 1-inch (25mm) of all poles shall be free from visible compression wood. 5.4.3 Dead streaks A
49、 single, sound dead streak is permitted in western red cedar and northern white cedar, provided the greatest width of the streak is less than 1/4 of the circumference of the pole at the point of measurement. 5.4.4 Defective butts Hollowing in the butt caused by “splinter pulling“ in felling the tree is permitted, provided that the area of such a hollow is less than 10% of the butt area. Hollow heart or decay, or both, is permitted in cedar poles only, provided the aggregate area of the hollow heart or decay, or both, does not
