Ansi a14.3 Escaleras

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ANSI ALLi-3 84 M 2575532 OOOB35h h ANSI A14.3-I984 for ladders - fixed - safety requirements COPYRIGHT American National Standards Institute Licensed by Information Handling Services COPYRIGHT American National Standards Institute Licensed by Information Handling Services

Transcript of Ansi a14.3 Escaleras

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A N S I ALLi-3 84 M 2 5 7 5 5 3 2 OOOB35h h ANSI A14.3-I984

for ladders - fixed -

safety requirements

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A N S I A 1 4 . 3 8 4 m 2575512 0008157 8 m

American Approval of an American National Standard requires verification by ANSI that the re- quirements for due process, consensus, and other criteria for approval have been met by National the standards developer.

Standard 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. Sub- stantial agreement means much more than a simple majority, but not necessarily unanim- ity. Consensus requires that all views and objections be considered, and that a concerted effort be made toward their resolution.

The use of American National Standards is completely voluntary; their existence does noi in any respect preclude anyone, whether he has approved the standards or not, from man- ufacturing, marketing, purchasing, or using products, processes, or procedures not con- forming to the standards.

The American National Standards Institute does not develop standards and will in no cir- cumstances give an interpretation of any American National Standard. Moreover, no per- son 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 inter- pretations should be addressed to the secretariat or sponsor whose name appears on the 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CAUTION NOTICE: This American National Standard may be revised or withdrawn at any time.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 to reaffirm, revise, or withdraw this standard no later than five years from the date of approval. Purchasers of American National Standards may receive current infor- mation on all standards by calling or writing the American National Standards Institute.

hblished by

American National Standards Institute 1430 Broadway, New York, New York 10018

Copyright O 1984 by American National Standards Institute, Inc 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 States of America

A i %M584/7

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- ANSI A34.3 84 2575512 0008358 T =

ANSI@ A 1 4.3- 1 984

Revision of ANSI A14.3-1974

Secretariat

American Ladder Institute

Approved January 13, 1984

American National Standards Institute, I ne

American National Standard for Ladders -

Fixed - Safety Requirements

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A N S I A I l l . 3 8 l l W 2575512 0008159 I W

Foreword (This Foreword is not part of American National Standard ANSI A14.3-1984.)

This standard is a revision of American National Standard Safety Requirements for Fixed Ladders, ANSI A14.3-1974. It is one of a series of five standards prepared under the super- vision of American National Standards Committee on Safety in the Construction, Care, and Use of Ladders, A14. All five standards have been developed by subcommittees reporting to American National Standards Committee A14. The subcommittees are: A14-1, Portable Wood Ladders; A14-2, Metal Ladders; A14-3, Fixed Ladders; A14-4, Job-Made Ladders; and A14-5, Portable Reinforced Plastic Ladders.

Ail five standards derive from the original American National Standard Safety Code for Construction, Care, and Use of Ladders, A14, which was first approved in 1923. Revi- sions were approved in 1935, 1948, and 1952. Prior to the 1948 revision, the Code con- tained some treatment of metal and fured ladders. Requirements for these types of lad- ders were removed from the 1948 revision, which became American National Standard Code for Wood Ladders, ANSI A14.1-1948, because, in the opinion of the committee, the rapid development in the metal ladder field warranted special consideration and treatment of metal ladders and fured ladders (usually metal) in separate standards.

Subcommittee A14-3 was created for the purpose of reviewing the data on fixed ladders originally contained in the Code prior to the 1948 revision, and making any changes or additions necessary to conform to the requirements of all interested groups. The A14.3 standard was submitted to the A14 Committee for letter ballot in December 1955 and was approved in 1956. A revision was published in 1974.

The present revision was begun in 1979 and was approved in 1981. However, an appeal led to reconsideration by the A14 Committee, and the current version was finally ap- proved in 1984. Significant changes are in the statement of exceptions to the application of this standard and in the lengths of climbs as covered by this standard.

Suggestions for improvement of this standard will be welcome. They should be sent to the American Ladder Institute, 11 1 East Wacker Drive, Chicago, IL 60601,

This standard was processed and approved for submittal to ANSI by American National Standards Committee on Safety in the Construction, Care, and Use of Ladders, A14. Committee approval of the standard does not necessarily imply that all committee mem- bers voted for its approval. At the time it approved this standard, the A14 Committee had the foliowing members:

Lewis W. Berger, Chairman Norman R. Pugh, Secretary

Organization Represented Name of Representative Aiüance of American insurers. . . . . . . . . . . . . . . . . . . . . . . . . . . . .Thomas F. Bresnahan The Aluminum Association . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Edward E. Cooke

W. W. Pritsky (Ait) Robert I. Werner (Ait)

American Institute of Architects . . . . . . . . . . . . . . . . . . . . . . . . . . .Robert H. Lee American Insurance Association . . . . . . . . . . . . . . . . . . . . . . . . . . .David P. JVinger

Thomas E. Murray (Ait) American iron & Steel Institute. . . . . . . . . . . . . . . . . . . . . . . . . . . .Edward E. Wilkinson American Ladder Institute. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Henry W. Buschman, JI

Associated General Contractors of America, Inc . . . . . . . . . . . . . . . . . .Robert Sample

Association of American Railroads . . . . . . . . . . . . . . . . . . . . . . . . . .Paul V. Duffy Canadian Standards Association. . . . . . . . . . . . . . . . . . . . . . . . . . . .Robert Reid Edison Electric Institute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .David C. Norman

J. P. Markey (Ait) Electronic Industries Association . . . . . . . . . . . . . . . . . . . . . . . . . . .Gary Redman

James B. Dorenbusch (Alt)

Arthur L. Schmuhi (Ait)

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PAGE Contents 1 . General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

1.1 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1.2 Purpose . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1.3 Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1.4 Pitch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1.5 Exceptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1.6 Existing Installations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1.7 Interpretation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1.8 Mandatory and Advisory Rules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

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2 . Related Standards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 2.1 Related American National Standards . . . . . . . . . . . 1 . . . . . . . . . . . . . . 7 2.2 Other Related Standards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

3 . Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

1.9 Equivalent . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 1.10 Recognized Design Practice . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4 . General Design Criteria . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 4.1 Maximum Ladder Lengths and Protection Requirements . . . . . . . . . . . . . . 8 4.2 Design Loads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 4.3 Design Stresses and Fabrication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 4.4 Design Supervision . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

5 . Design Details for Fixed Ladders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 5.1 StepsandRungs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 5.2 Side Rails . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 5.3 Terminations at the Top of a Ladder . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 5.4 Clearances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 5.5 Grounding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 5.6 Moisture Resistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

6 . Design Details for Cages. Wells. and Platforms . . . . . . . . . . . . . . . . . . . . . . . . . . 12 6.1 Cages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 6.2 Wells . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 6.3 Platforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - 1 2

7 . Ladder Safety Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 7.1 General Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 7.2 Safety Factors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 7.3 Ladder Safety Devices Consisting of a Carrier. Safety Sleeve. and

Safety Belt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 7.4 Ladder Safety Devices of Other Designs . . . . . . . . . . . . . . . . . . . . . . . . . 13

8 . Protective Finishes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 8.1 Metal Ladders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 8.2 WoodLadders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 8.3 Combined Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

9 . Maintenance and Use of Ladders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 9.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 9.2 Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 9.3 Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

10 . Revision of American National Standards Referred to in This Document . . . . . . . 15

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A NSI AILI -3 8 4 H 2595512 0 0 0 8 1 b l T

Organization Represented Name of Representative Exchange Carriers Standards Association . . . . . . . . . . . . . . . . . . . . . .Jonathan L. Shaw

Peter J. Speronza (Alt) Industrial Safety Equipment Association . . . . . . . . . . . . . . . . . . . . . .J. Nigel Ellis

Ailen Neustater (Ait) Frank E. Wilcher, Jr (Ait)

International Brotherhood of Electrical Workers . . . . . . . . . . . . . . . . . .Robert L. Bieritz International Brotherhood of Painters and Allied Trades George J. Jones International Magnesium Association. . . . . . . . . . . . . . . . . . . . . . . . Clayton E. Larson International Union of Bricklayers and Allied Craftsmen . . . . . . . . . . . . .Merlin L. Taylor Metal Ladder Manufacturers Association, . . . . . . . . . . . . . . . . . . . . . .Richard L. Werner

Motor Vehicle Manufacturers Association ..................... .Kenneth E. Lauck

. . . . . . . . . . . .

Jerrold F. Hilton (Ait)

Joseph A. Calcaterra (Alt) Richard J. Carpenter (Ait)

Robert J. Lyons (Alt) National Association of Architectural Metal Manufacturers. . . . . . . . . . . .Philip B. Neilson

National Association of Government Labor Officials. . . . . . . . . . . . . . . .Howard Williams National Fire Protection Association. . . . . . . . . . . . . . . . . . . . . . . . .Samuel C. Cramer

National Retail Merchants Association. . . . . . . . . . . . . . . . . . . . . . . .Harold W. Stillman, JI National Safety Council . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Bernie Enfield Steel Plate Fabricators Association, Inc . . . . . . . . . . . . . . . . . . . . . . .Earl A. Bratton

Underwriters Laboratories. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Edward Killoren

U.S. Consumer Product Safety Commission* . . . . . . . . . . . . . . . . . . . .Roy Deppa US. Department of the Army, Corps of Engineers* . . . . . . . . . . . . . . . .Ronald J. Larch U.S. Department of Labor, OSHA*. . . . . . . . . . . . . . . . . . . . . . . . . .Roy Gurnham

Ronald Bennett (Ait)

Thurmond Yost (Ait)

Wiiliam R. Hooper (Ait)

Individual Member John E. Johnson

Subcommittee Al 4-3 on Fixed Ladders, which developed this standard, had the follow- ing members:

Bernie Enfield, Chairman Ronald Bennett Thomas F. Bresnahan D. Engh R. A. Kleine Hugh McRae Harold Wincheii Thurmond Yost

*Nonvoting advisory member.

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SECTION PAGE

Figures Fig . 1 Pitch of Fixed Ladders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - 1 5

Length of Climb 24 ft or Less - Cage. Well. or Ladder Safety Device Not Required . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Length of Climb 24 ft or Less with Elevated Access - Cage or Ladder Safety Device Required . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Single Length of Climb Greater Than 24 ft but Not Exceeding 50 ft - Cage. Well, or Ladder Safety Device Required . . . . . . . . . . . . . . . 17 Total Lengths of Climb Greater Than 50 ft - Platforms and Cages.

Support and Ladder Dimensions and Side Clearances . . . . . . . . . . . . . . . 19

Fig . 2

Fig . 3

Fig . 4

Fig . 5

Fig . 6 Wells, or Ladder Safety Devices Required ....................... 18

Fig . 7 Individual Rung Ladders - Suggested Design of Rungs . . . . . . . . . . . . . . 20 Fig . 8 Termination a t Floor or Platform ............................ 20 Fig . 9 Terminations at Roof . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Fig . 10 Grab Bars . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Fig . 11 General Arrangements for Ladders in Wells ...................... 22

Fig . 13 Counterbalanced Hatch Cover at Roof . . . . . . . . . . . . . . . . . . . . . . . . . 24 Fig . 14 Minimum Ladder Clearances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Fig . 16 Example of the General Construction of Cages .................... 27 Fig . 17 Example of a Cage Plan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

Fig . 12 Deflector Plate for Hatch Opening with Reduced Clearance . . . . . . . . . . . 24

Fig . 15 Through Ladder Clearances - Ladder Placed Far from Wall . . . . . . . . . . . 26

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American National Standard for Ladders - Fixed - Safety Requirements

1. General

1.1 Scope. This standard prescribes minimum require- ments for the design, construction, and use of fixed ladders, and sets forth requirements for cages, wells, and ladder safety devices used with fixed ladders, in order to minimize personal injuries. Au parts and ap- purtenances necessary for a safe and efficient ladder shall be considered integral parts of the design.

1.2 Purpose. The purpose of this standard is to provide safety for life, limb, and property by establishing mini- mum standards for the design and installation of fixed ladders.

1.3 Application. The methods employed to ensure compliance with this standard shall be determined by the proper regulatory or administrative authority.

1.4 Pitch. This standard covers fixed ladders within the pitch range of 60 to 90 degrees from the horizontal.

1.4.1 Preferred Pitch. The preferred pitch of fixed ladders shail be considered to be within the range of 75 to 90 degrees from the horizontal (see Fig. 1).

1.4.2 Substandard Pitch. Fixed ladders shall be con- sidered substandard if they are installed within the sub- standard pitch range of 60 to 75 degrees from the hori- zontal. Substandard fixed ladders shall be permitted only where it is found necessary to meet installation conditions (see Fig. 1). This substandard pitch range shall be considered a critical range, to be avoided if possible.

1.4.3 Pitch Greater Than 90 Degrees. Ladders hav- ing a pitch in excess of 90 degrees from the horizontal shall not be permitted.

1.5 Exceptions 1.5.1 This standard is intended for application to

the types of structures depicted and described in the standard (i.e., buildings, wells, and shafts). It sets forth the criteria (what is needed) necessary to build a fixed ladder in a certain way and manner (how to build). The standard does not contemplate special or unique (as to where and when) applications of the require- ments, although individual requirements, or a combina- tion of requirements, may apply universally.

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1 S .2 This standard establishes requirements for fixed ladders in order to promote a greater degree of standardization. In cases where difficulty is encountered in complying with the standard, or where there are special service conditions, it is expected that the ad- ministrative authority will grant exceptions from the literal requirements of the standard, or will permit the use of alternative designs or features, if equivalent safety is thereby secured (see 1.9).

1.6 Existing Installations

apply to existing installations, provided they meet one of the following conditions:

a state, federal, or consensus standard that was in existence and applicable at the time of instaliation, and documentation is available to substantiate this.

(2) The installation differs from the design mea- surements of this standard by a degree, determined by an individual competent in structural design, such that its performance will not substantially deviate from the requirements of this standard.

1.6.2 If the existing installation is subsequently modified or replaced, or if repairs on more than 25 per- cent of the total unit are required, the installation shall be made to conform to the requirements of this standard.

1.6.1 The requirements of this standard shall not

(i) The installation was made in compliance with

1.7 Interpretation 1.7.1 This standard is designed to serve as a guide

for regulatory bodies or administrative agencies in the formulation of laws and regulations. It is also intended for voluntary use by establishments that use or de- sign fixed ladders, or manufacture them for installa- tion.

1.7.2 To secure uniform application of this stan- dard, it is recommended that suggestions involving changes in the requirements or disputes over their interpretation be referred to the organization holding the secretariat of this standard:

American Ladder Institute, 11 1 East Wacker Drive, Chicago, IL 60601.

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1.8 Mandatory and Advisory Rules. Mandatory re- quirements of this standard are indicated by the word “shall.” If a requirement is of an advisory nature, it is indicated by the word “should” or is stated as a recommendation.

1.9 Equivalent. The word “equivalent” in this stam dard shall be interpreted to mean an alternative de- sign, feature, construction, connection, or material providing equal performance.

1.10 Recognized Design Practice. The term “recog- nized design practice” in this standard shall be inter- preted to mean the use and application of those specifications contained in the standards cited in Section 2 and 4.3.

2. Related Standards

2.1 Related American National Standards. This stan- dard is intended for use with the following American . National Standards (see Section 10).

American National Standard Requirements for Safety Belts, Harnesses, Lanyards, Lifelines, and Drop Limes for Construction and Industrial Use, ANSI A10.14- 1975

American National Standard Safety Requirements for Floor and Wall Openings, Railings, and Toeboards, ANSI A12.1-1973

American National Standard Safety Code for Ladders - Portable Wood - Safety Requirements, ANSI

American National Standard Safety Code for Eleva- tors and Escalators, ANSI/ASME A17.1-1981

American National Standard Lightning Protection Code, ANSI/NFPA 78-1983

2.2 Other Related Standards Specification for the Design, Fabrication and Erection of Structural Steel for Buildings, AISC S31O-198O1

Specification for Structural Steel, ASTM A36-8 la2

Al 4.1-1 982

.

Construction Manual Series, Section 1, Specifications for Aluminum Structures, AA SAS-30-19823

Available from American Institute of Steel Construction, P.O. Box 4588, Chicago, IL 60680. *Available from ASTM, 1916 Race Street, Philadelphia, PA €9103. 3Available from The Aluminum Association, 818 Connecti- cut Avenue, NW, Washington, DC 20006.

2595512 0008Lbl l 5 m

AMERICAN NATIONAL STANDARD A14.3-1984

National Design Specification for Wood Construc- tion, 19824

3. Definitions

cage. A barrier, which may be referred to as a cage guard OK basket guard, that is an enclosure mounted on the side rails of the fixed ladder or fastened to the structure to enclose the climbing space of the ladder in order to safeguard the employee climbing the ladder.

carrier. The track of a ladder safety device consisting of a flexible cable or rigid rail, which is secured to the ladder or structure by mountings.

fastening. Attaching a ladder to a structure, building, or equipment.

ladder. A device incorporating or employing steps, rungs, or cleats on which a person may step to ascend or descend.

ladder safety device. A vertical support system, other than a cage or well, used in conjunction with a ladder, which will limit a person’s fall from the ladder without that person having to continually manipulate the de- vice or any part thereof.

landing. Any area such as the ground, roof, or plat- form that provides access/egress for a fixed ladder.

length of climb. The total vertical distance a person could climb in traveling between the extreme points of access/egress for a fxed ladder, whether the lad- er is of an unbroken length or consists of multiple sections. This total vertical distance is determined by including all spaces between all ladder steps or rungs and all other vertical intervening spaces between the extreme points of access/egress.

mounting. A means for attaching a cage or a ladder safety device to a ladder.

pitch. The included (acute) angle between the hori- zontal and the ladder, which is measured on the op- posite side of the ladder from the climbing side. The pitch is usually expressed as H/L, which is the hori- zontal distance, H , from the base of the ladder to the supporting surface divided by the working length, L , of the ladder.

platform. A landing surface that is used as a working or standing location.

‘Available from National Forest Products Association, 1619 Massachusetts Avenue, NW, Washington, DC 20036.

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A N S I A L 4 9 3 Bi-I 2575532 000Blb5 7

AMERICAN NATIONAL STANDARD A14.3-1984

rail. The side members jointed at intervals by either rungs or steps.

rail ladder. A fixed ladder consisting of side rails joined at regular intervals by rungs and fastened full length or in sections to a building, structure, or equipment.

safety belt. A high-strength belt or harness attached to a fall-limiting device that is worn by individuals working at elevated locations and specifically designed to secure, suspend, or retrieve the user.

safety sleeve. That part of a ladder safety device con- sisting of the moving component with locking mechan- ism that travels on the carrier and makes the connec- tion between the carrier and the safety belt.

side-step ladder. A rail ladder that requires a person getting off at the top to step sideways from the ladder in order to reach a landing.

step surfaces. The clear portions of steps or rungs on which a person may step while ascending or descend- ing a ladder.

through ladder. A rail ladder that requires a person getting off at the top to step through the ladder in order to reach a landing.

toeboard. A barrier erected along the exposed edges of a platform or landing surface to prevent falls of ma- terials or tools that would create hazards to persons below.

well (shaft). A walled enclosure around a fixed ladder that provides the person climbing the ladder with the same protection as a cage.

4. General Design Criteria

4.1 Maximum Ladder Lengths and Protection Requirements

4.1.1 A cage, well, or ladder safety device shall not be required where the length of climb is 24 feet or less above or below ground level, or above or below a floor or roof with accesslegress from ground level, floor, or roof (see Fig. 2).

4.1 .i A cage or ladder safety device shall be pro- vided where the length of climb is less than 24 feet but the top of the ladder is at a distance greater than 24 feet above ground level, floor, or roof (see Fig. 3).

4.1.3 A cage, well, or ladder safety device shall be provided where a single length of climb is greater than 24 feet but does not exceed 50 feet (see Fig. 4).

4.1.4 Ladders having a length of climb greater than 50 feet (see Fig. 5a) shall be provided with a cage, well,. or ladder safety device and shall meet the requirements in 4.1.4.1 or 4.1.4.2, whichever is applicable.

4.1.4.1 Where cages or wells are used: (1) The ladder shall consist of multiple sections. (2) Each section shall be horizontally offset from

(3) A landing platform shall be provided at least adjacent sections.

every 50 feet within the length of climb. 4.1.4.2 Where ladder safety devices are used, the

length of climb may be continuous, but rest platforms shall be provided at maximum intervals of 150 feet (see Fig. 5b).

tions shall be free of sharp edges, burrs, or other de- tails that may be hazardous to the person using the ladder.

4.1.5 All parts and surfaces of fixed ladder installa-

4.2 Design Loads. All ladders, platforms, appurtenances, and fastenings shall be designed to meet the load re- quirements described in 4.2.1 through 4.2.3,

4.2.1 Live Loads for Ladders 4.2.1.1 Live Loads Imposed by Persons, Live

loads imposed by persons shall be as follows: (1) The minimum design live load shall be two

loads of 250 pounds each concentrated between any two consecutive attachments. Each step or rung in the ladder shall be designed for a single concentrated live load of 250 pounds minimum.

(2) The number and position of additional concen- trated live load units of 250 pounds each, determined from anticipated usage of the ladder, shall be consid- ered in the design.

4.2.1.2 Other Live Loads. The following live loads shall be considered in the design, where appli- cable :

(1) A uniform coating of ice on all parts of the ladder

(2) A wind load on all parts of the ladder (3) The weight of rigging attached to the ladder,

.

including the load to be lifted

use of ladder safety devices 4.2.1.3 Live Load Concentration. All live loads

shall be considered to be concentrated at such a point or points as will cause the maximum stress in the struc- tural member in question.

4.2.2 Live Loads for Platforms. All platforms shall be designed for a uniform minimum live load of 100 pounds per square foot over the entire platform area; for the live loads resulting from ladders secured direct- ly to the platforms; and for other live loads as indi- cated in 4.2.1.2.

. (4) Anticipated impact loads resulting from the

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A N S I A L 4 - 3 B Y 25755112 000BLbb 7 U

4.2.3 Dead Loads 4.2.3.1 Ladders. The weight of the ladder and

attached appurtenances shall be considered simultane- ously with the live loads in the design of rails, supports, and fastenings.

4.2.3.2 Platforms. The weight of the platform and attached appurtenances, including the dead load of any portion of the ladder supported by the plat- form, shall be considered simultaneously with the live loads in the design of platform framing supports and fastenings.

4.3 Design Stresses and Fabrication 4.3.1 Steel

4.3.1.1 Ladders and Platforms. Steel ladders and platforms shall be designed and fabricated in ac- cordance with the applicable requirements of AISC S310-1980. Portable steel ladders may be adapted for use as fured ladders provided they mee€ all the requirements of ANSI A14.3-1984.

4.3.1.2 Materials. Materials conforming to ASTM A36-81a or the equivalent shall be used. Higher strength steels may be used, subject to the require- ments of AISC S310-1980:

conform to all applicable requirements of AISC S310- 1980.

4.3.1.3 Welding. Welding for steel ladders shall

4.3.2 Aluminum 4.3.2.1 Ladders and Platforms. Aluminum lad-

ers and platforms shall be designed and fabricated in accordance with the applicable requirements of AA SAS-30-1982. Portable aluminum ladders may be adapted for use as fixed ladders provided they meet all the requirements of ANSI A14.3-1984.

priate temper (as defined by AA SAS-30-1982) shall be used. Other aluminum alloys may be used subject to the requirements of AA SAS-30-1982.

shall conform to all applicable requirements of AA

4.3.2.2 Materials. Alloys 6061 or 6063 of appro-

4.3.2.3 Welding. Welding for aluminum ladders

SAS-30-1 982. 4.3.3 Wood

4.3.3.1 Wood ladders shall be designed and fabricated in accordance with applicable requirements of ANSI A14.1-1982, with the following additional restrictions :

1982 shall be used as fixed wood ladders. (i) Only single ladders as prescribed in ANSI A14.1-

(2) The design loads shall be as specified in 4.2

(3) The minimum clear width between side rails a t of ANSI A14.3-1984.

any point shall not be less than 16 inches, and side rails shall be parallel at all points.

(4) Fastenings meeting the design load requirements

AMERICAN NATIONAL STANDARD A14.3-1984

shaU be used for the permanent attachment of wood ladders to structures, buildings, or equipment.

cordance with the allowable stresses and fabrication practices of National Design Specification for Wood Construction, 1982.

4.3.4 Other Materials. Materials other than steel, aluminum, and wood may be used provided the design, fabrication, and erection are in accordance with recog- nized design practice.

4.4 Design Supervision. The design of fured ladder systems shall be under the general supervision of a qualified registered (licensed) structural or professional engineer or architect.

4.3.3.2 Wood platforms shall be designed in ac-

5 . Design Details for Fixed Ladders

5.1 Steps and Rungs

and rungs shall not exceed 12 inches on centers, and this spacing shall be uniform in the same length of climb (see Fig. 6)

5.1.2 Width. The minimum inside clear width of step surface for steps and rungs shall be 16 inches, and this width shall be uniform in the same length of climb (see Fig. 6) .

5.1.1 Vertical Spacing. The vertical spacing of steps

5.1.3 Minimum Size of Steps and Rungs 5.1.3.1 General. The following are general re-

quirements for the minimum size of steps and rungs: (i) The minimum size (cross section) requirements

of steps and rungs specified 5.1.3 are based on sec- tion properties adequate to support the design loads specified in 4.2 and on the minimum clear width speci- fied in 5.1.2.

(2) For additional load concentrations or attach- ment of ladder safety devices, and for clear widths ex- ceeding 16 inches, the minimum size (cross section) of steps and rungs shali be increased in accordance with recognized design practice.

of steps and rungs be less than 314 inch, as specified in 5.1.3.2(1), regardless of the material used.

be uniform in the same length of climb.

sections) of steps and rungs fabricated of steel con- forming to ASTM A36-81a shall be as follows:

(1) For ladders subject to normal atmospheric ex- posures, 3/4-inch-diameter solid bar, or the.equivalent in strength for square, rectangular, or other solid or hollow shapes, is required.

(3) In no case shall the minimum size (cross section)

(4) The size (cross section) of steps and rungs shall

5.1.3.2 Steel Ladders. The minimum sizes (cross

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ANSI A1493 8 4 = 2575512 0008Lb7 O W

AMERICAN NATIONAL STANDARD A14.3-1984

( 2 ) For ladders subject to unusually corrosive atmo- spheric exposures, 1-inch-diameter solid bar, or the equivalent in strength for square, rectangular, or other solid or hollow shapes, is required.

5.1.3.3 Aluminum Ladders. The minimum size of aluminum structural components shall be determined in accordance with the provisions of AA SAS-30-1982. In cases where the ladders are subjected to corrosive atmospheric exposure or placed in contact with dis- similar materials, the aluminum shall be treated in ac- cordance with the requirements of AA SAS-30-1982.

5.1.3.4 Ladders of Other Metals. The minimum size (cross section) as specified in 5.1.3.2 may be modi- fied (subject to the requirement of 5.1.3.1(3)) by a factor that shall be the ratio of the allowable unit stress for steel conforming to ASTM A36-8 1 a to the allowable unit stress for the type and shape of the other metal(s) used.

wooden steps and rungs shall be as specified in ANSI 5.1.3.5 Wood Ladders. The minimum size of

A14.1-1982. 5.1.4 Rung Ends

5.1.4.1 Step- and Rung-vpe Ladders. Step- and rung-type ladders of steel, aluminum, and other metals shall have each step or rung end securely fastened to the side rails so as to fully develop the strength of the step or rung, and so as to securely lock each step or rung to the side rails.

5.1.4.2 Individual Rung Ladders 5.1.4.2.1 Rungs Attached to Metals. The

ends of each rung shall have the proper configuration and sufficient means of attachment to the supporting structure to fully develop the design loads imposed on the rung.

Masonry. The ends of each rung shall have proper con- figuration and sufficient embedment in the supporting wall to fully develop the design loads imposed on the rung (see Fig. 7).

5.1.4.3 Wood Ladders. Rung ends shall be in accordance with the requirements of ANSI A14.1-. 1982.

5.1.4.2.2 Rungs Embedded in Concrete or

5.2 Side Rails 5.2.1 Shape

5.2.1.1 Any shape may be used that provides a uniform gripping surface for the hands of persons using the ladders, as long as that shape provides a power grip.

maintained for all ladders in the same length of climb.

power grip shall not be used.

5.2.1.2 The same shape of side rails shall be

5.2.1.3 Side rail shapes that fail to provide a

5.2.2 Minimum Size 5.2.2.1 General. The following are general re-

quirements for the minimum size of side rails: (1) The minimum size (cross section) of side rails

recommended in 5.2.2 is based on section properties adequate to support the design loads specified in 4.2 and on the maximum spacing of supports specified in 5.2.4. Variations in size (cross section) shall be per- mitted provided the section properties are adequate to support the design loads and are consistent with the maximum spacing of supports.

(2) For additional load concentrations or attach- ment of ladder safety devices, and for spacing of sup- ports that exceeds the maximum spacing recom- mended, the minimum size of side rails shall be in- creased in accordance with recognized design practice.

(3) The same size (cross section) of side rails shall be maintained for ail ladders in the same length of climb.

mum sizes (cross section) of side rails fabricated of steel conforming to ASTM A36-81a are as follows:

posures, flat solid bar stock, 2-1/2 inches wide by 318-inch thick, or the equivalent in strength in solid or hollow shapes, is required.

(2) For ladders subject to unusually corrosive at- mospheric exposures, flat solid bar stock 2-1/2 inches wide by 1/2-inch thick, or the equivalent in strength in solid or hollow shapes, is required.

5.2.2.3 Aluminum Ladders. The minimum size of aluminum structural components shall be deter- mined in accordance with the provisions of AA SAS- 30-1 982. In cases where the ladders are subjected to corrosive atmospheric exposure or placed in contact with dissimilar materials, the aluminum shall be treated in accordance with requirements of AA SAS-30-1982.

side rails for wood ladders shall be as required in ANSI

5.2.2.2 Steel Ladders. The recommended mini-

(1) For ladders subject to normal atmospheric ex-

5.2.2.4 Wood Ladders. The minimum size of

A14.1-1982. 5.2.2.5 Ladders of Other Materiais. The mini-

mum size recommended for steel may be modified by a factor that shall be the ratio of the allowable unit stress for steel conforming to ASTM A36-81a to the allowable unit stress for the type and shape of other metal(s) used.

5.2.3 Splices 5.2.3.1 AU splices shall be designed so as to en-

sure full structural continuity of the side rails. Splices shall be made at intermediate supports only if the type of material used requires that location.

tions with the main side rails so as to afford minimum interference with the gripping surface for the hands

5.2.3.2 Au splices shall provide smooth transi-

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of each person using the ladder. Sharp or extensive projections shall not be permitted.

5.2.3.3 Provisions for expansion due to thermal changes shall be made at splices if these provisions are required to prevent buckling or buildup of stresses in the side rails.

5.2.4 Maximum Spacing of Supports 5.2.4.1 Steel Ladders. The maximum spacing of

supports for fastening the side rails to the structure, building, or equipment shall be 10 feet O inches for the size of side rails recommended in 5.2.2, and for the clear widthof steps or rungs specified in 5.1.2. For additional design loads or attachment of ladder safety devices, or for variations in size (cross section) of side rails, the maximum spacing of supports shall be ad- justed in accordance with recognized design practice (see, e.g., Fig. 6 and 15).

Wood, and Other Materials. The maximum spacing of supports for fastening the side rails to the structure, building, or equipment shall be as required to ade- quately support the loads, subject to the same require- ments specified for steel in 5.2.4.1.

5.2.4.2 Ladders Constructed of Aluminum,

5.3 Terminations at the Top of a Ladder

of a ladder shall be level with the top of the access/ egress level or landing platform served by the ladder (see Fig. 8,9 , and lo), except as required by 5.3.4.2 or as permitted in 6.2.1 -2.

5.3.1 Top Step or Rung. The top of a step or rung

5.3.2 Extensions for Side-Rail Ladders 5.3.2.1 The side rails of throughor side-step

ladders shail extend 3 feet 6 inches above the top of the access/egress Ievel or landing platform served by the ladder (see Fig. 8 ,9 , and 10). For a parapet ladder, the accesslegress level shall be the roof if the parapet is cut to permit passage through the parapet; if the parapet is continuous, the access/egress level shall be the top of the parapet (see Fig. 9).

5.3.2.2 For through ladder extensions, the steps or rungs shall be omitted from the extension and tlfe extension of the side rails shall be flared to provide not less than 24 inches, or more than 30 inches, clearance between side rails. Where ladder safety devices are pro- vided, the maximum clearance between side rails of the extensions shall not exceed 36 inches (see Fig. 8).

the steps or rungs shall be continuous in the extension (see Fig. 6).

5.3.3 Extensions for Individual Rung Ladders

tended for manholes (see Fig. 11) and terminations with hatches (see 5.3,4), shall be extended above an accesslegress level or landing platform either by the

5.3.2.3 For side-step ladders, the side rails and

5.3.3.1 Individual rung ladders, except those in-

2595512 00081b4 2 = AMERICAN NATIONAL STANDARD A14.3-1984

continuation of the rung spacings as horizontal grab bars or by providing vertical grab bars that shall have the same lateral spacing as the vertical legs of the rungs (see Fig. 10).

5.3.3.2 Grab bars shall extend at least 3 feet 6 inches above the accesslegress level or landing plat- form served by the ladder.

grab bars shall be the same as for ladder rungs (see 5.1.3). 5.3.3.3 The minimum size (cross section) of the

5.3.4 Terminations with Hatches 5.3.4.1 Hatches shall meet the minimum in-

side clearances specified for wells in 6.2.2. In the case of unusual hatch condi€ions, the clearance on the climbing side may be reduced to 24 inches from the centerline of the steps or rungs if the underside of the hatch opening is fitted with a deflector plate (see Fig. 12).

5.3.4.2 Counterbalanced hatch covers shall open at least 70 degrees from the horizontal. The springs or other counterbalance mechanisms for the hatch may project into the hatch opening provided they do not reduce the clear width of access/egress to less than 24 inches. The top rung of the ladder may also be located below the top of the hatch to provide required clearance for the hatch cover (see Fig. 13).

5.4 Clearances 5.4.1 Climbing Side of Ladders

5.4.1.1 Ladders without cages or wells shail have a minimum perpendicular distance of 30 inches from the centerline of the steps and rungs to the nearest permanent object on the climbing side (see Fig. 14).

5.4.1.2 Ladders with cages or wells shall have clearances as specified in Section 6.

5.4.1.3 When unavoidable obstructions are en- countered, the minimum clearance may be reduced to 24 inches if deflector plates are provided (see Fig. 14).

5.4.2 Back Side of Ladders 5.4.2.1 The perpendicular distance from the cen-

terline of the steps and rungs, or grab bars, or both, to the nearest permanent object in back of the ladder shall be not less than 7 inches (see Fig. 8 and lo), ex- cept in elevator pits complying with clearance require- ments as specified in ANSIIASME A17.1-1981.

5.4.2.2 For a through ladder, the step-across distance from the centerline of the steps or rungs to the nearest edge of the structure, building, or equip- ment shall not be less than 7 inches or more than 12 inches. If the normal step-across distance exceeds 12 inches, a landing platform shall be provided toxeduce the distance to between 7 and 12 inches (see Fig, 15).

5.4.3 Width or Side Clearances 5,4.3.1 Ladders without cages or wells shall have

a minimum clear width to the nearest permanent ob-

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AMERICAN NATIONAL STANDARD A14.3-1984

ject of at least 15 inches on each side of the centerline of the ladder (see Fig. 6).

5.4.3.2 Side-step ladders at the point of access/ egress to a platform shall have a step-across distance of 15 inches minimum and 20 inches maximum from the centerline of the ladder (see Fig. 6).

clearances as specified in Section 6. 5.4.3.3 Ladders with a cage or well shall have

5.5 Grounding. Lightning protection, bonding, and grounding of metal ladders and attachments shall be in accordance with ANSI/NFPA 78-1983.

5.6 Moisture Resistance. All fixed ladders shall be de- signed to minimize the accumulation of moisture so as to help reduce corrosion on metal ladders or rot of wood ladders.

6. Design Details for Cages, Wells, and Platforms

2 5 9 5 5 1 2 0 0 0 B l b ï 4 =

6.1 Cages 6.1.1 General Design

6.1.1.1 The general construction of cages shall consist of horizontal bands or supports and vertical bars. An example of cage construction is shown in Fig. 16 and 17, but equivalent construction may be used.

side rails of rail ladders, or directly to the structure, building, or equipment for individual rung ladders.

6.1.1.3 Vertical bars shall be on the inside of the horizontal bands and shall be fastened to them.

6.1.1.4 Cages shall be designed to support the live loads and dead loads specified for ladders in 4.2.1 and 4.2.3.

6.1.1.2 Horizontal bands shall be fastened to the

6.1.2 Cage Size 6.1.2.1 Cages shall extend not less than 27

inches, or more than 30 inches from the centerline of the step or rung (excluding the flare at the bottom of .

the cage), and shall not be less than 27 inches in width. The inside of the cage shall be clear of projections.

6.1.2.2 Horizontal bands shall be spaced not more than 4 feet on center vertically for the size and spacing of vertical bars recommended in the example shown in Fig. 16 and 17. For variations in size (cross section) and spacing of vertical bars, the maximum spacing of horizontal bands shall be in accordance with recognized design practice.

6.1.2.3 Vertical bars shall be spaced at intervals not more than 40 degrees on center around the circum- ference of the cage. This will give a maximum spacing, center to center, of approximately 9-1/2 inches (see Fig. 17).

12

6.1.2.4 The bottom of the cage shall be at a level not less than 7 feet or more than 8 feet above the point of access/egress to the bottom of the ladder. The bot- tom of the cage shall be flared not less than 4 inches all around within the distance between the bottom hori- zontal band and the next higher band (see Fig. 16).

w e r e practical difficulties are encountered, cages may start at 10 feet above the point of access/egress.

of 3 feet 6 inches above the top of the platform, or the point of access/egress at the top of the ladder, with provision for access/egress to the platform or point of access/egress (see Fig. 16).

6.1 -2.6 Any portion of the cage above the plat- form or above the point of access/egress that cannot be fastened to the side rail shall be fastened to the guard- rail, or directly to the structure, building, or equipment.

6.2 Wells

6.1.2.5 The top of the cage shall be a minimum

6.2.1 General Construction 6.2, l . l Wells shall consist of a wall or walls, or

equivalent construction, completely encircling the lad- er. The inside of the well shall be clear of projections (see Fig. 11).

6.2.1.2 The top rung or step of the ladder shall meet the requirements specified in 5.3.1, except that individual rung ladders may have the top step or rung located not more than 6 inches below the top of the well or access/egress point.

6.2.1.3 The top of the well shall have railings and toeboards in accordance with ANSI A12.1-1973, and arranged as to provide safe access/egress for the well.

6 . 2 2 Well Size 6.2.2.1 The inside face of the well on the climb-

ing side of the ladder shall extend not less than 27 inches or more than 30 inches from the centerline of the step or rung. The inside clear width of the well shall be a nominal 30 inches (see Fig. 11).

6.2.2.2 The bottom of the wall on the access side shall start at a level not less than 7 feet or more than 8 feet above the.point of access to the bottom of the ladder (see Fig. 11).

6.3 Platforms 6.3.1 General Construction

6.3.1.1 Platforms shall consist of a horizontal area on which a person may step while climbing a lad- der, either for rest purposes or for access to another section of the ladder.

6.3.1.2 All platforms shall be provided with railings and toeboards, in accordance with ANSI A12.1- 1973.

6.3.2 Platform Size, The total depth of the plat- form shall provide a minimum space of 30 inches from

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the centerline of the ladder on the climbing side. The width of the platform shall be not less than 30 inches.

7. Ladder Safety Devices

7 , l General Design 7.1.1 AU components of ladder safety devices shall

meet the design requirements of Section 7. 7.1.2 The ladder safety device shall allow at least

two persons, but not more than four, averaging 250 pounds each (including equipment), to ascend or descend simultaneously; however, oníy one person at

. a time (except in rescue operations) shall use the same portion of carrier between intermediate mountings for rigid carriers or cable guides for flexible carriers.

7.1.3 The ladder safety device shall be designed to absorb the impact load of a solid object weighing at least 500 pounds in a free fall of 18 inches.

reduce the design safety factors of the fixed ladders.

safety devices.

7.2 Safety Factors 7.2.1 Flexible components such as webbing and

fabric shall have a safety factor of not less than 5 for the designed static load.

7.2.2 Flexible carriers shall have a safety factor not less than 10 times the designed static load.

7.2.3 Ductile material shall have a safety factor of not less than 5 times the designed static load.

7.3 Ladder Safety Devices Consisting of a Carrier, Safety Sleeve, and Safety Belt

be operated entirely by the person using the ladder safety device. It shall permit the person using the lad- der safety device to ascend or descend without having to continually manipulate the safety sleeve.

7.3.2 The maximum length of movement of the safety sleeve, in an accidental fall, shall be not more than 6 inches.

7.3.3 The maximum length of the connection be- tween the centerline of the carrier and the point of attachment to the safety belt shall not exceed 9 inches.

7.3.4 Mountings for rigid carriers shall be attached at each end of the carrier with intermediate mountings spaced along the entire length of the carrier in accor- dance with the manufacturer’s recommendations. Intermediate mountings shall be installed within 1 foot below each splice on the carrier, and not less than one every 25 feet.

7.3.5 Mountings for flexible carriers shall be at- tached at each end of the carrier. Cable guides utilized

7.1.4 Design and installation of mountings shall not

7.1.5 Brittle materials shall not be utilized in ladder

7.3.1 The safety sleeve shall be of a type which can

.AMERICAN NATIONAL STANDARD A14.3-1984

with a flexible carrier shall be installed at a minimum spacing of 25 feet and a maximum spacing of 40 feet along the entire length of the carrier.

7.4 Ladder Safety Devices of Other Designs. Ladder safety devices utilizing other designs shall meet the de- sign requirements of this standard, including the re- quirements of 7.1 and 7.2.

8. Protective Finishes

8.1 Metal Ladders 8.1.1 If carbon-steel rail ladders and carbon-steel

individual rung ladders attached to metal are exposed to the elements, to minimize corrosion they shall re- ceive a prime coat of paint and one (or more) field finish coat(s) of paint; or shall be hot-dip galvanized; or shall receive equivalent methods of metal protec- tion. -

8.1.2 Carbon-steel individual rung ladders em- bedded in masonry or concrete shall be hot-dip gal- vanized as protection against corrosion at the critical points where the rung metal enters the masonry or con- crete. Equivalent protective methods may also be used.

8.1.3 For all carbon-steel ladders exposed to con- tinuously moist conditions, hot-dip galvanizing is rec- ommended as protection except where the moisture condition is also corrosive to galvanizing, in which case special coatings shall be provided or a noncorrosive metal used.

or other noncorrosive metals do not require painting, except that those portions of the ladders in contact with dissimilar metals or embedded in masonry or con- crete shaii be painted or otherwise protected in ac- cordance with recognized maintenance practice.

8.2 Wood Ladders. Wood ladders shall normally be treated with a nonirritating preservative suitable for the service. Wood ladders may be painted, after the preservative treatment, in accordance with the require- ments of ANSI A14.1-1982.

8.3 Combined Materials. When different types of ma- terials are used in the construction of fixed ladders, the materials used shall be treated at their interfaces with suitable protective materials, as necessary, to prevent any deleterious effects of one material on the other.

8.1.4 The exposed portions of ladders of aluminum

9. Maintenance and Use of Ladders

9.1 General 9.1.1 The guidelines discussed in this section do not

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AMERICAN NATIONAL STANDARD A14.3-1984

constitute every proper or improper procedure for the maintenance and use of ladders.

9.1.2 Proper use of the fixed ladder systems will contribute significantly to safety. Haste, sudden move- ments, lack of attention during use, ladder condition (worn or damaged), and user’s age and physical condi- tion contribute to falls. The footwear employed by the user may also contribute to falls. The likelihood of falls is not increased by the user’s excessive weight or size. However, improper climbing posture creating user clumsiness on the ladder may cause falls.

9.1.3 The safe useful life of the fixed ladder sys- tems is dependent on its proper in-service maintenance. While ladders are designed for extended service, it is necessary to provide periodic in-service maintenance to ensure their continued safe use. Ladders are not de- signed or intended to possess an infinite safe useful life.

9.2 Use 9.2.1 When ascending or descending, the climber

shall face the ladder and shall maintain a firm hold on the ladder with both hands.

or otherwise secured so as not to create a hazard while climbing.

9.2.3 Heavy objects shall be hoisted aloft and so lowered.

9.2.4 Users shall report any defects or deteriora- tion promptly to their supervisors.

9.2.5 Ladders should be free of oil, grease, or slippery materials on climbing or gripping surfaces. Shoes and footwear should be kept clean.

9.2.2 Hand tools shall be carried in a pouch, holster,

9.3 Maintenance 9.3.1 Ail fixed ladder systems should be maintained

in a safe condition. Inspections for rust, corrosion, and deterioration should be made at least annually, with more frequent inspections to be made as determined by use and exposure.

before a ladder is used, and no ladder should be used if any fastenings or welds are missing, or if the joints be- tween the rungs and the side rails are not tight.

9.3.3 Where structural damage or defects make a ladder hazardous, the ladder shall be taken out of ser- vice and either repaired by a competent individual or blocked, fenced, or removed so that it cannot be used.

9.3.4 When repairs are made to fixed ladder sys- tems, the materials used should be at least the equiva- lent of the original constrúction.

regularly scheduled inspections and maintenance to fixed ladder systems.

9.3.2 All bolts and welds shall be in place and secure

9.3.5 Records should be maintained of annual or

9.3.6 If grounding protection has been provided for

14

the ladder, then the ground connection (or connec- tions) to the ladder shall be inspected for continuity at least annually.

be inspected in accordance with the manufacturer’s recommendations.

9.3.8 Depending on the geographical location of the ladder and the amount of ultraviolet rays (sun- light) to which a glass-fiber-reinforced plastic ladder is subjected, periodic maintenance to overcome deteriora- tion may be required. As a result of the abovementioned conditions, some degree of glass fiber prominence may be apparent. If this condition is evident, it is suggested that the following procedure be used to cover the ex- posed glass fiber.

The ladder should be washed with a suitable com- merical solvent or liquid detergent solution compatible with its composition and allowed to air dry, Safety procedures involving adequate ventilation, no smoking, and proper personnel protective equipment shall be employed when using these substances, Handling of the ladder after it has been washed should be kept to a minimum. The ladder rail should be brushed or sprayed with a good commercially available grade of acrylic lacquer, polyurethane coating, or other suitable ma- terial. Depending on the degree of glass fiber promi- nence, one or two coats may be required. It is ím- portant to read and use the directions supplied by the various material manufacturers of any substance used in a maintenance program.

9.3.9 If a glass-fiber-reinforced plastic fixed ladder is to be installed out-of-doors, it is recommended that a coat of good commercially available slip-resistant paste wax or other suitable material be used on the fiberglass side rails of the ladders. This will greatly de- crease the possibility of glass fiber prominence. It is further suggested that a semiannual coating program be carried out to ensure longevity of the ladder. It is important to read the instructions supplied by the vari- ous material manufacturers of any substance used in a maintenance program. Glass-fiber-reinforced plastic ladders that are used in areas of high humidity, such as the seacoast atmosphere, should be coated with one of several commercially available materials, which will significantly enhance the life and the appearance of the ladder. The ladder supplier should be contacted for recommended practices to be followed in this field (in-service) maintenance program.

9.3.10 Ladders of wood or wood components may be coated with a nonconductive finish such as varnish, shellac, or a clear or tinted preservative. Lad- ders shall not be coated with any opaque covering ex- cept for a minimum amount needed for identification or warning, and then only on one face of the side rails.

9.3.7 If a ladder safety device is provided, it should

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Page 17: Ansi a14.3 Escaleras

A N S I A34 .3 4 4 W 2 5 7 5 5 3 2 0 0 0 8 3 7 2 i.I = AMERICAN NATIONAL STANDARD A14.3-1984

10. Revision of American National Standards Referred to in This Document

When the American National Standards referred to in this document are superseded by a revision ap- proved by the American National Standards Institute, Inc, the revision shall apply.

t

- FIXED LADDER RANGE -7

O0

Fig. 1 Pitch of Fixed Ladders

15

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Page 18: Ansi a14.3 Escaleras

A N S I A311-3 8Ll W 2575532 0008373 b W

AMERICAN NATIONAL STANDARD A14.3-1984

n- -3 f t 6 in MIN

-ASCENT 24 ft OR LESS

GROUND LEVEL, FLOOR, OR ROOF

P A S E E FIG.11 FOR I - I

DESCENT 24 f t OR LESS

Fig. 2 Length of Climb 24 ft or Less - Cage, Well, or

Ladder Safety Device Not Required

-3 f t 6 in MIN

- 24 f t OR LESS

CAGE OR LADDER SAFETY DEVICE

-GREATER THAN 24 f t

7 f t MIN 8 f t MAX I t

Fig. 3 Length of Climb 24 ft or Less with Elevated Access -

Cage or Ladder Safety Device Required

16

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Page 19: Ansi a14.3 Escaleras

GREATER THAN 24 f t NOT TO EXCEED 50ft

GROUND LEVEL, FLOOR, OR ROOF

EXCEED 50ft

Fig. 4 Single Length of Climb Greater Than 24 ft but Not Exceeding 50 ft -

Cage, Well, or Ladder Safety Device Required

17

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Page 20: Ansi a14.3 Escaleras

A N S I A34.3 8 4 = 2575532 0008375 T m

AMERICAN NATIONAL STANDARD A14.3-1984

- 50 f t M A X EACH SECTION

-50 f t MAX

- 5 O f t MAX

- ASCENT DESCENT

(a) Multiple Sections, 50 f t Max Each Section When Cages or Wells Are Provided

(Ladder Safety Devices May Also Be Used)

LADDER SAFETY DEVICE-

- 150 f t

- i50ft MAX

GROUND LEVEL, FLOOR, OR ROOF

ELEVATION SIDE VIEW

(b) 'Continuous Length of Climb 150 f t Max

between Platforms When Ladder Safety Device Is Provided

Fig. 5 Total Lengths of Climb Greater Than 50 ft - Platforms and Cages,

Wells, or Ladder Safety Devices Required 18

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Page 21: Ansi a14.3 Escaleras

12-in MAX CENTERS, ALL RUNGS

16-in CLEAR WIDTH MIN BETWEEN SIDE RAILS

IO f t O-in NOMINAL MAX SPACING OF SUPPORTS (SEE 5.2.4)

MIN CLEARANCE TO ANY PERMANENT OBSTRUCTION FOR LADDER WITHOUT CAGE OR WELL

4 SUPPORT SPACING, LADDER

3 f t 6 in MIN

15

7 i n MIN 12 in MAX

SIDE CLEARANCES FOR SIDE-STEP LADDERS DIMENSIONS AND SIDE CLEARANCES

Fig. 6 Support and Ladder Dimensions and Side Clearances

19

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Page 22: Ansi a14.3 Escaleras

ANSI Al4.3 84 = 2575532 0008177 3

AMERICAN NATIONAL STANDARD A14.3-1984

MIN

CROSS SECTION

Fig. 7 Individual Rung Ladders - Suggested Design of Rungs

DEVICE IS USED

R PLATFORM __ _ _ .~

WALL ANCHOR

STEPS OR RUNGS

GRATING PLATFORM rFLOOR FASTENER

FLOOR OR Il,,/ PLATFORM L I N E 7

-7 in MIN ___I

: . . . ... , , . .. .. -9 . Q .,

: d . + , '

Q. v .

. . ..Y ..y . ? . . . . . . . . .

:p 0:. .'

' 4 ., .q.' . . . Q . .

EL EVA? I

Fig. 8 Termination at Floor or Platform

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Page 23: Ansi a14.3 Escaleras

A N S I A1Li.3 8 4 m 2575512 0008178 5 m

AMERICAN NATIONAL STANDARD A14.3-1984

MIN - 3 f t

I -3 f t 6 in MIN

TOP OF RUNG

FLUSH WITH ROOF3

ACCESS OVER PARAPET

ACCESS THRU PA RA PET

Fig. 9 Terminations at Roof

7T

1 r f t 6 i n p

FLUSH WITH STOP

ACCESS OVER GRAVEL STOP

I ' I

Fig. 10 Grab Bars

VERTICAL

21

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Page 24: Ansi a14.3 Escaleras

ANSI A34.3 8 4 W 2575532 0 0 0 8 3 7 7 7 W

AMERICAN NATIONAL STANDARD A14.3-1984

$ LADDER AND WELL II 7 i n MIN

5 in

LADDER 7 in M I N 1 , AND WELL

NOMINAL-

RAIL LADDER IN DIViDUAL RUNG LADDER

ia) Horizontal Sections Rectangular Wells

i I

22

-3

RAIL LADDER

'4 -h MIN, 37- in MAX ' 4 -h MIN, 37- in M WELL DIAMETER T WELL DIAMETER

(b) Horizontal Sections

Circular Wells

Fig. 1 1 General Arrangements for Ladders in Wells

INDIViDUAL RUNG LADDER

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Page 25: Ansi a14.3 Escaleras

23

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Page 26: Ansi a14.3 Escaleras

A N S I A 3 4 . 3 8 4 2575532 0008383 5 W

AMERICAN NATIONAL STANDARD A14.3-1984

24-in MIN REDUCED CLEARANCE (SEE FIG.11 FOR NORMAL CLEARANCES) r 1 f CURB

o

Fig. 12 Deflector Plate for Hatch Opening with Reduced Clearance

CLEARANCE AS

~ U T O M A T I C HOLD-OPEN

AND OPERATING ARMS, ONE EACH SIDE

HATCH WIDTH

FACE-FACE OF 24 in

OPERATING ARMS

24

Fig. 13 Counterbalanced Hatch Cover at Roof

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Page 27: Ansi a14.3 Escaleras

A N S I A L 4 - 3 A4 a 2575532 0008382 7

AMERICAN NATIONAL STANDARD A14.3-1984

o *

(5

NORMAL CLEARANCE REDUCED-CLEARANCE DEFLECTOR PLATE FOR

H E A D HAZARDS

Fig. 14 Minimum Ladder Clearances

25

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Page 28: Ansi a14.3 Escaleras

I AMERICAN NATIONAL STANDARD A14.3-1984

-10 ft O in MAX

-10 f t O in MAX (SEE 5.2.4)

Fig. 15 Through Ladder Clearances - Ladder Placed Far from Wall

26

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A N S I A1'4.3 8'4 2575512 O008184 O W

AMERICAN NATIONAL STANDARD A14.3-1984

A" 2 x -in HORIZONTAL BANDS/ 18 in M I N 7

I t 1 T

15 in MIN3 u 27 in MIN

IZ r 3 0 i n MAX 20 in MAX

.- a .I- Yi

Po

ACCESS THROUGH ACCESS LATERALLY LADDER FROM LADDER

Fig. 16 Example of the General Construction of Cages

1 3 2 16 I- X- -in

VERTICAL BARS7

EXAMPLE F CAGE ELEVATION

27

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Page 30: Ansi a14.3 Escaleras

ANSI A14.3 84 2595512 0008185 2

AMERICAN NATIONAL STANDARD A14.3-1984

-7 in MIN-1 f t 2 i n _I_I f t 3 in RADIUS- I III I...,.

I

3 I

r L

-

I

I

2 x 4 - i n HORIZONTAL i

I 1 3 12x16 - in VERTICAL

Fig. 17 Example of a Cage Plan

28

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Page 31: Ansi a14.3 Escaleras

American National Standards

The standard in this booklet is one of 8000 standards approved to date by the American National Standards Institute.

The Standards Institute provides the machinery for creating voluntary stan- dards. it serves to eliminate duplication of standards activities and to weld conflicting standards into single, nationally accepted standards under the designation "American National Standards."

Each standard represents general agreement among maker, seller, and user groups as to the best current practice with regard to some specific problem. Thus the completed standards cut across the whole fabric of production, distribution, and consumption of goods and services. American National Standards, by reason of Institute procedures, reflect a national consensus of manufacturers, consumers, and scientific, technical, and professional orga- nizations, and governmental agencies. The completed standards are used widely by industry and commerce and often by municipal, state, and federal governments.

The Standards institute, under whose auspices this work is being done, is the United States clearinghouse and coordinating body for voluntary standards activity on the national level. It is a federation of trade associations, techni- cal societies, professional groups, and consumer organizations. Some 1 O00 companies are affiliated with the Institute as company members.

The American National Standards Institute is the United States member of the International Organization for Standardization (IS01 and the Interna- tional Electrotechnical Commission (I EC). Through these channels U.S. stan- dards interests make their positions felt on the international level. American National Standards are on file in the libraries of the national standards bodies of more than 60 countries.

American National Standards Institute, Inc 1430 Broadway

New York, N.Y. 10018

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Ready Access to the World's Standards through ANSI

Are you seeking a standard vital to your interests? Turn to the American National Standards Institute, which performs a unique function as America's clearinghouse and information center for national, international, regional, and foreign standards.

ANSI is the sole source of all approved American National Standards. In addition, the institute is the U.S. source for al l international standards and drafts of the International Organization for Standardization (ISO), International Electrotechni- cal Commission (IEC), and of the publications of I S 0 member bodies. And that's not all . . .

Here's a capsule summary of the wealth of materials available from ANSI -

STANDARDS

O Al l approved American National Standards in print. A standing order service is available to standards users who wish to receive new and revised standards automatically.

O IS0 and IEC International Standards O IS0 Draft International Standards e IEC Six Months' Rule Drafts O CEN Proposals - Draft European Standards developed and issued for preliminary vote by the European Committee for Standardization ICEN).

e CENEL EC/CECC Proposals - Draft specifications issued by CECC, the Electronic Components Committee of the European Committee for Electrotechnical Stan- dardization (CENEL ECI

~Standards of 89 national standards organizations that belong to IS0 O English translations of thousands of foreign standards

CATALOGS

O Annual Catalog of American National Standards. Supplements are published

O Latest catalogs issued by /SO, IEC, and 55 members o f IS0 e Foreign catalogs in English translation specialized listings o f American National Standards in fields ranging from in for- mation processing to safety and health

several times a year,

Available in Microform

American National Standards are available in microform from: Information Han- dling Services, Inverness Business Park, 15 Inverness Way East, P.O. Box 1154, Englewood, Colorado 801 IO; te l (303) 779-0600: and from Information Mar- keting, Inc, 13251 Northend Street, Oak Park, Michigan 48237; te l (313) 546-6706. All I S 0 and IEC standards may be obtained in microform from Information Han- dling Services.

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