1、Fall-ArrestSystems Practical EssentialsbyAndrew C. SulowskiFor information about updates and seminars for thisCSA publication, please contactCSA International178 Rexdale BoulevardToronto, OntarioM9W 1R31-800-463-6727www.salescsa-international.orgFall-ArrestSystems PracticalEssentialsby Andrew C. Sul
2、owskiPublished in January 2000byCSA International178 Rexdale BoulevardToronto, OntarioCanadaM9W 1R3AcknowledgementsThe author would like to express his gratitude to Mr. James W. Brinkley,Director, H.G. Armstrong Aerospace Medical Research Laboratory in Dayton,Ohio and to Dr. Jean Arteau of the Insti
3、tut de recherche en sant du travail(IRSST) in Montral, Qubec for their thorough review of the text and theirinsightful comments.The author would also like to thank the staff of CSA International, and inparticular Kim Emmerson, Manager, Seminars Program, Gary Burford,Managing Editor, and Samantha Coy
4、le, Editor.DisclaimerThe purpose and scope of this publication are limited to information about fallarrest equipment commonly used by people who are exposed to the hazard offalling when working. The information and advice contained in thispublication are not intended to replace training in fall prot
5、ection by acompetent person.CSA International and the author assume no responsibility for the use of thispublication or any information contained herein. Brand names andmanufacturers of equipment are mentioned only when it is necessary to do so. Endorsement of specific equipment is not implied.ISBN
6、1-894416-92-9Production Editor: On-line EditingManaging Editor: Gary BurfordAdministrative Assistant: Elizabeth Del RizzoDocument Processors: Hematie Hassan/Indira KumaralaganEditors: Maria Adragna/Samantha Coyle/Sandra Hawryn/Ann Martin/John McConnellGraphics Coordinator: Cindy KerkmannPublishing S
7、ystem Coordinators: Ursula Das/Grace Da Silva/Seetha RajagopalanSGML Project Manager: Alison MacIntosh Andrew C. Sulowski 2000All rights reserved. No part of this publication may be reproduced inany form whatsoever without prior permission.CSA International Fall-Arrest Systems Practical Essentials3J
8、anuary 2000ContentsPreface 60. Introduction 70.1 Background 70.2 Ten Essential Principles for Users of Fall-Arrest Systems 91. Ten Essential Principles: How to Follow Them 101.1 Inspection Before Use 101.1.1 General 101.1.2 Harnesses 101.1.3 Shock Absorbers 111.1.4 Lanyards 111.1.5 Self-Retracting L
9、ifelines (SRLs; Retractable Lifelines) 131.1.6 Self-Retracting Lanyards (Retractors) 161.1.7 Fall Arresters and Lifelines 171.1.8 Connecting Hardware and Anchorage Connectors 181.1.9 Anchorages 191.1.10 Horizontal Lifelines (HLLs) 201.2 Donning Harnesses 211.2.1 General 211.2.2 Donning Procedure 211
10、.2.3 Specific Procedures 221.3 Shock Absorbers and Shock-Absorbing Lanyards 231.4 Compatible Connecting Hardware 231.4.1 General 231.4.2 Assessing Compatibility 231.5 Suitable Anchorage 241.6 Fall Distance 241.7 Conditions of the Workplace 251.8 Care of Equipment 261.9 Post-Fall Rescue 261.10 Fall-P
11、rotection Training 272. Ten Essential Principles: Why Follow Them 282.1 Inspection Before Use 282.1.1 General 282.1.2 Harnesses 292.1.3 Shock Absorbers 30PLUS 1156 CSA International4January 20002.1.4 Lanyards 312.1.5 Self-Retracting Lifelines 342.1.6 Self-Retracting Lanyards 362.1.7 Fall Arresters a
12、nd Lifelines 372.1.8 Connecting Hardware and Anchorage Connectors 442.1.9 Anchorages 452.1.10 Horizontal Lifelines 462.2 Harnesses 472.2.1 General 472.2.2 Primary Functions 482.2.3 Secondary Functions 482.2.4 Harness Classification 482.2.5 General Design Features 492.2.6 Suspension 522.2.7 Special D
13、esign Features 522.3 Shock Absorbers and Shock-Absorbing Lanyards 532.3.1 General 532.3.2 Functions 552.3.3 Total Fall Distance (TFD) 552.3.4 Increasing Shock-Absorbing Capacity 562.3.5 Maximum Arrest Force 572.4 Compatible Connecting Hardware 602.4.1 General 602.4.2 Connections 622.4.3 Carabiners 6
14、32.4.4 Anchorage Connectors 642.4.5 Conclusions 652.5 Suitable Anchorage 652.5.1 General 652.5.2 Strength 662.5.3 Stability 692.5.4 Location 702.6 Fall Distance 722.6.1 General 722.6.2 Total Fall Distance (TFD) 732.6.3 Maximum TFD 752.6.4 Required Minimum Clearance (min CR) 762.6.5 Bottoming Out 772
15、.7 Conditions of the Workplace 782.7.1 General 782.7.2 Rain 782.7.3 Ice 792.7.4 Dust 79CSA International Fall-Arrest Systems Practical Essentials5January 20002.7.5 Grease 792.7.6 Chemicals 802.7.7 Electricity 802.7.8 Heat and High Temperature 802.8 Care of Equipment 802.9 Post-Fall Rescue 812.9.1 Ge
16、neral 812.9.2 Rescue Plans 812.9.3 Secondary Hazards 822.10 Fall-Protection Training 83Figures 86Appendix A Bibliography 110PLUS 1156 CSA International6January 2000PrefaceThis is the first edition of CSA Special Publication PLUS 1156, Fall-ArrestSystems Practical Essentials. There are very few books
17、 on fall protection, inspite of considerable interest in the subject. PLUS 1156 is intended to respondto this interest and to assist fall-arrest system users in making the best possibleuse of the equipment provided by employers for their workers safety. Userssafety was the main objective in the deve
18、lopment of this book. As well,employers who encourage their workers to study this book should benefit fromimproved workers safety through a reduction in injuries and fatalities, as wellas the associated reduction in legal liability.PLUS 1156 was designed to assist workers who have been trained in fa
19、llprotection and are applying their newly acquired knowledge at work. It is not areplacement for, or an alternative to, proper training provided by a personcompetent in fall protection. A typical fall-arrest system consists of a variety ofdevices made of several different materials. Proper fall-prot
20、ection trainingdeals with many aspects of handling ropes and materials; it is crucial forcompetent fall protection. For people who have already mastered thesesubjects, PLUS 1156 may serve as a refresher course and as a reference manual.The format of this book was designed to provide both practical a
21、ndtheoretical information on fall- arrest systems. Clause 1 briefly describes theten essential principles and their application; Clause 2, numbered in parallelwith Clause 1, discusses the importance of the principles in more detail andprovides background information and examples.January 2000Notes:(1
22、) Use of the singular in this publication does not exclude the plural (and vice versa)when the sense allows.(2) CSA publications are subject to periodic review, and suggestions for theirimprovement will be referred to the appropriate committee.(3) All enquiries regarding this publication should be a
23、ddressed to CSA International,Standards Development, 178 Rexdale Boulevard, Toronto, Ontario M9W 1R3.CSA International Fall-Arrest Systems Practical Essentials7January 2000PLUS 1156Fall-Arrest Systems Practical Essentials0. Introduction0.1 BackgroundFall protection has developed during the past twen
24、ty-five years into anindependent, cohesive, and relatively complex field of safety engineering. Thiscomplexity is especially apparent in fall-arrest systems. These systems, whenused correctly, arrest accidental falls by workers in situations where preventingfalls is not feasible.The fall event is dy
25、namic in nature. Therefore, all the phenomena that takeplace during the arrest of an accidental fall by a fall-arrest system (FAS) arealso dynamic. During the fall-arrest action, every component of the fall-arrestsystem is subject to momentary shock load, including the users harness, shockabsorber,
26、lanyard, fall arrester, vertical lifeline, or self-retractinglifeline/lanyard. So too is a horizontal lifeline, an anchorage, and all theconnecting hardware. Each and every component of the fall-arrest system mustbe able to withstand the dynamic forces occurring in the FAS with the requiredmargin of
27、 safety.These dynamic forces are always greater than the weight of the personfalling. This is because of the sudden deceleration of the falling mass. Theforces involved are much greater than the static weight of the fall victim,increasing by a factor as low as two when free-fall distance is negligib
28、le, to fourif a shock absorber has been employed, to thirty and higher for some horizontallifelines. The most common standard mass for a fall victim is 100 kg or 220 lb. The permissible shock load acting on the fall victim is limited by fall protectionregulations in the United States and Canada to 8
29、 kN (1800 lb).A fall-arrest system is the very last line of defence against fall hazards. Thefirst and best defence is to eliminate the hazards, if at all possible. Unfortunately, in many cases this is prohibitively expensive and therefore notfeasible. The second defence is to prevent a fall, throug
30、h the construction ofbarriers, guardrails, covers, and so on. This method is widely practised,relatively inexpensive, and quite efficient.The third defence, fall arrest, becomes necessary when the first two approachesare not feasible. In such a case, it is accepted that a fall may occur, andemployer
31、s provide an FAS to catch a falling worker in mid-air and bring theindividual safely to a complete stop. The task is not always simple, particularlywhen safety nets are not practical and only a personal fall-arrest system may beused.PLUS 1156 CSA International8January 2000Detailed knowledge about fa
32、ll events tends to be highly specialized. Thecourse of studies in technical colleges does not yet deal with the engineeringissues related to dynamic forces in fall-arrest systems and to the plastic(permanent) and elastic (temporary) deformation of FAS components. Therehas been quite a bit of researc
33、h on and documentation of the medical aspects ofthe exposure of the human body to transitory deceleration, as these matters aredirectly related to the safety of flying personnel. However, these matters aretaught only as specialty courses at medical schools and in the field ofbiomechanics. Regulation
34、s and technical standards for fall protection are alsovery complex, even for safety personnel, as anybody would agree who tries todigest ANSI Standard Z359.1 or the Subpart M Safety Standards for FallProtection in the Construction Industry (1926.500503) issued by the U.S.Department of Labor.Even tho
35、ugh the regulations require that users of fall arrest systems beproperly trained and periodically retrained, few users will be fall-protectionspecialists. PLUS 1156 is written with these non-specialists in mind. If FASusers follow the ten essential principles presented in this guide, their fall-arre
36、stsystems will safely stop most falls. As well, their employers fall-protectionprogram will prove itself appropriate and efficient.The rules presented in this guide are simplified. They provide adequatedirection for a person trained in fall protection, but they are not the only rulesin fall-protecti
37、on engineering for safety professionals. FAS designers andstructural engineers who evaluate the strength of available anchorages must befamiliar with a vast array of technical, legal, medical, and other rules.CSA International Fall-Arrest Systems Practical Essentials9January 20000.2 Ten Essential Pr
38、inciples for Users of Fall-Arrest SystemsHere are ten simple and basic rules for using an FAS. Youshould follow them at all times.1. Inspect your equipment before every use.2. Don and adjust your harness properly.3. Use your shock absorber or your shock-absorbing lanyardwhenever possible.4. Connect
39、all components of your FAS using only compatibleconnecting hardware.5. Attach your FAS only to a suitable anchorage.6. Keep your fall distance to a minimum.7. Consider the conditions of your workplace when choosingyour equipment.8. Care for your equipment as you would care for yourself.9. Know the r
40、escue procedure and equipment in case youshould fall.10. Be properly trained to use any fall protection equipment.PLUS 1156 CSA International10January 20001. Ten Essential Principles: How to Follow Them1.1 Inspection Before Use1.1.1 GeneralBefore-use inspection is crucial to the safe, effective use
41、of fall-arrest systems. The following discussion is organized according to individual FAS components.1.1.2 HarnessesBefore you don your harness (Figure 1), visually inspect all straps and allstitched connections for cuts, excessive abrasion damage (such as fraying),damaged stitching with cut or pull
42、ed out threads, and missing straps (forexample, the waist strap and the chest strap).Look for burns, either complete or partial, and for chemical damage, whichmay appear either as localized discoloration of the webbing or as a local changein its pliability. Webbing affected this way may be either le
43、ss pliable and stifferthan the rest of the strap or more flexible. If you find any of the above problems,do not don the harness, but return it to your supervisor.Note that a used but still usable harness may have some dirt stains and mayshow some fraying on the straps. As long as there are no cuts o
44、r thinning of thestrap, such minor damage is acceptable. One pulled thread in a length ofstitching is not enough to cause rejection, unless the stitching comes undonewhen you pull on the protruding thread. Normally, the lock-stitch sewingemployed on harnesses does not allow the stitched connection t
45、o come undonewhen one broken thread is pulled.Visually inspect the harness hardware, including all buckles, D-rings, O-rings,and their strap attachment parts, such as plastic sliders for the D-ring and metalholders of the side D-rings. Look for cracks, bends, nicks, any corrosion inexcess of surface
46、 discoloration, and any other damage that could affect strengthor performance. Do not use the harness if you find any of these problems.Check grommets on all straps that are connected with tongue buckles. Damaged or missing grommets are not permissible in priority-one straps that areessential for th
47、e containment of the users body during a fall arrest. Somedamage, however, may be allowed on priority-two straps, the presence of whichis beneficial but not essential to the safe fall-arrest performance of the harness(see Clause 2.1.2.2 for more information about these priority categories).If your h
48、arness has free-sliding-bar buckles (Figure 2(a), make sure that allstrap keepers are present and capable of holding the free tails of straps. Thesebuckles may loosen up when the mating straps are not tensioned. For thisreason, free-sliding-bar buckles are not recommended on priority-one straps.If y
49、our harness is of the type that does not have a waist strap, ensure that theback D-ring is prevented from sliding too far down the shoulder straps, in caseCSA International Fall-Arrest Systems Practical Essentials11January 2000you have a head-first fall. Ask a qualified person for advice if there are nostoppers or other means to prevent such sliding (Figure 3).1.1.3 Shock AbsorbersVisually inspect the shock absorber (Figure 4) for pouch damage, such aspartially opene
