1、ANSI-ASC A14.8-2013American National StandardsAmerican National Standard Safety Requirements for Ladder AccessoriesANSI-ASCA14.8-2013American National Standard Safety Requirements for Ladder AccessoriesSecretariatAmerican Ladder Institute Approved May, 2013American National Standards Institute, Inc.
2、Free ladder safety resources are available from the American Ladder Institute at www.laddersafety.org. A Multimedia Training Program provides guidance on safe ladder selection, use and care at www.laddersafetytraining.org.For information on possible errata sheets and other ANSI-ASC A14 Standards ple
3、ase refer to the ALI website located at:www.americanladderinstitute.orgiAn American National Standard implies a consensus of those substantially concerned with its scope and provisions. An American National Standard is intended as a guide to aid the manufacturer, the consumer, and the general public
4、. The existence of an American National Standard does not in any respect preclude anyone, whether they have approved the standard or not, from manufacturing, marketing, purchasing, or using products, processes, or procedures not conforming to the standard. American National Standards are subject to
5、periodic review and users are cautioned to obtain the latest editions and errata sheets.The American National Standards Institute does not develop standards and will in no circumstances give an interpretation of any American National Standard. Moreover, no persons shall have the right or authority t
6、o issue an interpretation of an American National Standard in the name of the American National Standards Institute.CAUTION NOTICE: This American National Standard may be revised or withdrawn at anytime. The procedures of the American National Standards Institute require that action be taken to reaf
7、firm, revise, or withdraw this standard no later than five years from the date of publication. Purchasers of American National Standards may receive current information on all standards by calling or writing the American National Standards Institute.Published byAmerican Ladder Institute 330 N. Wabas
8、h Avenue, Suite 2000, Chicago, IL 60611Copyright by ANSI Accredited Standards Committee (ASC) A14 All rights reserved.No part of this publication may be reproduced in any form, in an electronic retrieval system or otherwise, without the prior written permission of the publisher.Printed in the United
9、 States of AmericaAmerican National StandardiiForeword(This foreword is not part of the American National Standard A14.8-2013)This standard on Ladder Accessories is one of the many American National Standards prepared under the ANSI Accredited Standards Committee on Safety in Construction, Care, and
10、 Use of Ladders. A14 Subcommittees that report to the A14 Standards committee have developed the following A14 Standards: A14.1 Portable Wood Ladders; A14.2 Portable Metal Ladders; A14.3 Fixed Ladders; A14.4 Job-made Ladders; A14.5 Portable Reinforced Plastic Ladders; A14.7 Mobile Ladder Stands and
11、A14.9 Disappearing Attic Stairways.This standard on Ladder Accessories was prepared under the supervision of the American National Standards A14 Accredited Standards on Safety in Construction, Care, and Use of Portable Ladders.The A14.8 Ladder Accessories sub-committee was first formed in 1990 to de
12、velop a standard that includes the most commonly used and manufactured ladder accessories. The standard was written as a guide to both manufacturers and end users alike to guide them in the proper care, use and selection of these accessories.This first edition of the American National Standard draws
13、 from the work that was done in the existing standards. The standard prescribes both general design requirements and specific design verification test requirements for each type of accessory. The primary intent behind the design verification testing is twofold. One, to test for the strength and inte
14、grity of the accessory itself, and the other to ensure the installed accessory does not have a detrimental effect on the intended performance of the ladder it is installed to. In addition, labeling, marking and instruction requirements are covered in this standard.Suggestions for improvement for the
15、 standard are welcome. They may be sent to American Ladder Institute, 330 N. Wabash Ave., Suite 2000, Chicago, IL 60611. All comments must be sent on the Official Comment Form that can be found on the last page of this document. Each comment must include a rationale.This standard was proposed and ap
16、proved for submittal to ANSI by the American National Standards Committee on Safety in the Construction, Care, and Use of Portable Ladders. Committee approval of the standard does not necessarily imply that all the committee members voted for its approval. At the time it approved this standard, the
17、A14 had the following members:Eric Knox, ChairmanDave Plotner, Vice ChairJanet Rapp, SecretariatiiiOrganization Represented Name of RepresentativeAmerican Insurance Association George EarhartAmerican Ladder Institute Ron SchwartzMarc McConnell (Alt)American Society of Safety Engineers Michael Lorenz
18、oAssociated General Contractors of America .Charles E. BirdCanadian Standards Association . Oreste SimonettaCosco Home and Office Products Eric KruseTerry Emerson (Alt)Featherlite Industries Garry Turgeon Wolfgang Gelhard (Alt)Illinois Association of Building Maintenance Contractors .Carl Pedersen J
19、ames Weil (Alt)International Brotherhood of Electrical Workers James TomaseskiInternational Brotherhood of Painters and Allied Trades .Greg RenneDan Penski (Alt)International Union of Bricklayers first, with the leveler set at maximum adjustment (maximum difference in height between the side rails o
20、f the ladder) and second, with the legs on a level surface (see Figure 8). When testing on a surface requiring maximum adjustment, an elevated platform must be provided for the opposite side. When testing on a level surface, both legs of manual levelers shall be fully extended.The test unit shall be
21、 placed at a 75- degree working angle, as shown in Figure 4, with both locks engaged. For combination ladders, a slightly modified angle shall be used so that the tread portion of the steps is horizontal (level). A downward distributed load, in accordance with Table 2, shall be applied for a period
22、of 1 minute to the top fly rung on ladders with extendable section(s) and to the top rung of single ladders or articulating ladders without extendable sections. The load shall be applied equally to both side rails using two 3-1/2 inch straps, each located next to a rail and centrally loaded through
23、an equalizer bar below the climbing side of the ladder. The leveler shall withstand this test without ultimate failure. Permanent deformation in the leveler or in other parts of the ladder structure due to the test is not a test failure. However, the ladder shall still support the test load after th
24、e application of the load, even if the leveler or other parts of the ladder assumed permanent deformation (set).9.3.1.4 Static Leveler Cantilever Bending Test. The leveler shall be attached to the base section of the ladder test unit as specified in 9.3.1. Any swiveling American National Standard A1
25、4.8-201311be measured by applying a test load, in accordance with Table 1, for a minimum period of one minute, to the bottom step, over a standard loading block located as near the side rail as possible with the ladder in a fully open position. The ladder equipped with a ladder leveler(s) shall be t
26、ested with the leveler(s) set at maximum adjustment (maximum difference in height) as shown in Figure 8a. If levelers are used on both the front and rear sections, both the front and rear levelers on the same side of the ladder shall be set at maximum extension and the opposite ladder legs supported
27、 so that the steps of the ladder are horizontal as shown in Figure 8a.The load shall be applied twice; first, next to the side rail with the leveler at full extension and then the test repeated with the load placed next to the opposite side rail. When the load is removed after each test, the leveler
28、 and ladder shall show no indication of test failure in the fastening means attaching the leveler to the ladder side rail. Permanent deformation in other parts of the leveler or ladder structure due to the test is not a test failure. However, the ladder shall still support the test load after the ap
29、plication of the load, even if other parts of the leveler or ladder assumed permanent deformation (set).9.3.2.3 Compression Test. A load test of the entire ladder equipped with a ladder leveler(s) shall be made with the leveler(s) set at the maximum adjustment (maximum difference in height). If leve
30、lers are used on both the front and rear sections, both the front and rear levelers on the same side of the ladder shall be set at maximum extension and the opposite ladder legs supported so that the steps of the ladder are horizontal as shown in Figure 8a.A uniformly distributed load, in accordance
31、 with Table 1, shall be applied for a minimum period of 1 minute to the top cap or platform (see Figure 3). A combination ladder shall be tested in its stepladder position, with the test load applied uniformly to the top cap, or to the top step when no top cap is used. Trestle ladders, articulated l
32、adders which permit their use as a double front stepladder, and the base section of extension trestle ladders shall be subjected to twice the test loads in Table 1, by applying the test load simultaneously to both sections of the ladder, at the top cap of each section, or to the top step when no top
33、 cap is used. The leveler and ladder shall withstand the load without test failure.9.3.2.4 Rail Cantilever Bending Tests.9.3.2.4.1 Front Rail Static Cantilever Bending Test. The front rail cantilever bending strength of a ladder equipped with a ladder leveler shall be A dead load of 200-lbs shall be
34、 applied centrally with a standard loading block (Figure 5) to the third highest rung of the test unit. A horizontal pulling force, statically applied equally to the bottom of the leveler legs at a distance at one inch above the test surface, shall not cause movement in excess of 1/4 inch across the
35、 test surface.9.3.1.6 Test Requirements for Levelers Requiring Replacement or the Addition of a Rung. Levelers that require the removal and replacement or the addition of a ladder rung as part of its installation or has a rung cross-section or means of attachment that differs from that of the ladder
36、 to which it is attached shall comply with the Rung Bending Test, Rung Shear Test and Rung Torque Test Requirements of the appropriate ANSI A14.2 or A14.5 standards.9.3.2 Ladder Leveler Tests For self-Supporting Ladders. The ladders used as test units for self-supporting ladder tests shall be a Ladd
37、er of the same duty rating (type IAA, IA, I, II or III), same type (step, trestle, combination, articulated), same material (wood, metal, reinforced plastic), and similar construction/design (box rail, solid shapes, riveted connections, other fastening means) for which the leveler is intended.The te
38、st unit for step, trestle and combination ladders shall be a 6ft. ladder size and for articulated ladders a 12ft. ladder size.9.3.2.1 Leveler Cantilever Bench Test. Dual Leg or Single Leg Levelers for self-supporting ladders shall be subjected to the Cantilever Bench Test as described in 9.3.1.1 and
39、 shown in Figures 6a the load attachment point on the C-clamp shall not be more than two inches below the underside of the leveler leg being tested. The weight shall be suspended so that it is acting through the vertical neutral axis of the leveler leg. The maximum allowable permanent deformation (s
40、et) of the test unit at the end of upper side rail is 1/4 inch.The test load shall then be applied to the extreme bottom end of the leveler leg attached to the lower side rail, in a like manner (see Figure 10). The maximum allowable permanent deformation (set) of the leveler leg attached to the lowe
41、r side rail is 1/4 inch.Provided the ladder continues to support the test load, permanent deformation (set) or ultimate failure of any ladder or leveler component as a result of the tests, except for the limitation on the maximum allowable permanent deformation (set) of the test unit upper and lower
42、 side rails, shall not constitute test failure.9.3.2.5 Foot Slip Test. Self-supporting ladders shall be tested for skid resistance as shown in Figure 2. The leveler shall be attached to a ladder test unit as specified in 9.3.2. The leveler shall be adjusted for use on a flat surface as shown in Appe
43、ndix A, Figures 8B or 8C, and tested on a plywood test surface as defined in Section 4.The plywood surface shall be sanded with new 320 grit sandpaper (garnet or aluminum oxide) and the dust removed with dry compressed air or a clean dry broom. Tests shall be conducted with all ladder feet placed on
44、 a clear area of the plywood face (i.e. NOT placed on areas of defects e.g. pin knots, patches, etc.) The ladder feet to be tested shall be cleaned with soap and water, rinsed clean of soap residue, and dried before testing.measured by applying an edgewise load to the bottom end of a leveler leg tha
45、t has been fully extended. Use appropriate means, prior to testing, to ensure that the test load is applied to the lower end of the leveler leg such as removing feet extending below the end of the leveler leg, or using special purpose test fixtures to load the leveler leg appropriately. The test uni
46、t shall be opened and placed on its side with the steps perpendicular to the ground as shown in Figure 10. Combination ladders shall be opened to their stepladder position. The lower side rail shall be clamped to a support and shall be unsupported from the bottom end of the leveler leg to the top of
47、 the bottom step. The top surface of the step shall be parallel to the edge of the support. Guides shall be used which have a nominal clearance between the front section rails to limit lateral movement of the section when the test load is applied.The test load shall be applied by means of a weight,
48、in accordance with Table 4, for a minimum period of one minute, to the extreme bottom end of the leveler leg attached to the upper side rail. The load shall be centrally applied to a 2-inch long block resting on the full width of the leveler leg and held in place by a C-clamp; the load attachment po
49、int on the C-clamp shall not be more than 2 inches below the underside of the leveler leg being tested. The weight shall be suspended so that it is acting through the vertical neutral axis of the leveler leg. The maximum allowable permanent deformation (set) of the test unit at the end of the upper side rail is 1/4 inch. The test load shall then be applied to the extreme bottom end of the leveler leg attached to the lower side rail in a like manner as shown in Figure 10. The maximum allowable permanent deformation (set) of the test unit at the end of the lower side rail is 1/4 inch.Provid
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