1、Designation: F2436 14Standard Test Method forMeasuring the Performance of Synthetic Rope Rescue BelaySystems Using a Drop Test1This standard is issued under the fixed designation F2436; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revisio
2、n, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers drop test procedures to measurerope rescue belay system performance. It applies
3、 only to belaysystems consisting of an untensioned rope connecting the loadto an anchored belay device. This test method does not addressother types of belays, such as self-belays or belays for leadclimbing, nor does it test the rescuers belaying ability.1.2 This test method may be used to help meas
4、ure a rescuebelay systems performance under controlled drop testconditions, but it will not necessarily provide guidance as towhich belay method is most suited to a particular application.Other considerations, such as ease of handling, performance ondifferent types and diameters of rope, portability
5、, versatility,system safety factor, cost, and automatic operation that do notrequire the positive action of the belayer may influence theselection of a belay system and are not dealt with in this testmethod. See X1.1.1.3 The values stated in SI units are to be regarded asstandard.1.4 This standard m
6、ay involve hazardous materials,operations, and equipment. This standard does not purport toaddress all of the safety concerns associated with its use. It isthe responsibility of whoever uses this standard to consult andestablish appropriate safety and health practices and deter-mine the applicabilit
7、y of regulatory limitations prior to use.Additional precautions for this test method are given in 8.1 and8.2.2. Referenced Documents2.1 ASTM Standards:2D1776 Practice for Conditioning and Testing TextilesF2266 Specification for Masses Used in Testing RescueSystems and Components2.2 Other Document:CI
8、 1801-98 Low Stretch and Static Kernmantle Life SafetyRope33. Terminology3.1 Definitions:3.1.1 belay, na secondary system, or the systemcomponents, used to arrest the load in the event of a failure inthe system.3.1.2 belay, vin rope rescue systems, to operate an unten-sioned secondary rope (belay li
9、ne) so that it may be taken in orlet out as the load is raised or lowered, and then hold the loadin case of failure of the lifting line (working line) system.3.1.3 belay assembly, nall elements of the belay system,but not including the belay line and the belay anchor.3.1.4 belay assembly extension,
10、L, (cm),nthe increase inlength of the belay assembly, due to stretch or other extension,measured from the anchorage to the farthest gripping point ofthe belay assembly while statically tensioned, post-drop, ex-pressed in centimetres (cm).3.1.5 belay device, nthat element of the belay systemproviding
11、 a moveable connection point to the belay line, whichcan secure the belay line when necessary.3.1.6 belay line, nin rope rescue systems, a secondaryline, generally untensioned, acting as a back-up to the liftingline as distinguished from the lifting line (working line) thatactually raises, lowers, o
12、r transports the load.3.1.7 belay system, nthe belay assembly and the belayline, but for the purposes of this test method, not including thebelay anchor.3.1.8 belay system extension, L, (cm),nthe distance belowthe zero line (this excludes drop height) reached at themaximum extension during fall arre
13、st, prior to rebound; alsoknown as stopping distance, expressed in centimetres (cm).3.1.9 belay system failure, nwhen the test block hits theground.1This test method is under the jurisdiction of ASTM Committee F32 on Searchand Rescue and is the direct responsibility of Subcommittee F32.01 on Equipme
14、nt,Testing, and Maintenance.Current edition approved Dec. 1, 2014. Published January 2015. Originallyapproved in 2005. Last previous edition approved in 2011 as F243605 (2011).DOI: 10.1520/F2436-14.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service
15、at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from Cordage Institute, 994 Old Eagle School Rd., Wayne, PA19087,http:/.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohoc
16、ken, PA 19428-2959. United States13.1.10 drop height, L, (cm),nthe free-fall distance theblock falls before the belay system begins to arrest its fall.3.1.11 elongation classification, nin rope rescue systems,elongation of new rope as measured by CI 1801-98 at 10 % ofthe manufacturers rated breaking
17、 strength: static 6 % and 10 % elongation3.1.12 extension, L,nthe change in length of a material,device, or system due to a change in an applied force, usuallymeasured at some specified force, force rate, or duration offorce, or combination thereof.3.1.13 final rope length, L, (cm), nthe distance be
18、tweenthe inside of the bowline where it contacts the shackle of thetest block and the lowest gripping portion of the belayassembly after the test block has rebounded and come to rest.3.1.14 lifting line, nthe line that lifts the test block andfrom which a quick disconnection is made to drop the test
19、block (working line).3.1.15 maximum arrest force, MAF, (N), nthe peak forcemeasured during the fall arrest.3.1.16 pre-grip slippage, L, (cm), nrope movementthrough the belay device before gripping stops movement.3.1.17 rope rescue system, na system using fiber ropes toraise, lower, or transport a lo
20、ad.3.1.18 zero line, nthe level of the contact between theinside of the bowline and test block shackle when it is 3 mbelow the lowest gripping portion of the belay assembly, priorto the drop.4. Summary of Test Method4.1 A rigid test block of the correct mass simulates a rescueload. A rope of given l
21、ength connects the test block to a belayassembly that is in turn connected to a suitably rigid overheadanchor point. The test block is raised a given distance with aseparate lifting system and is then released. After the block hasfree-fallen to its starting point, the belay system (the rope andbelay
22、 assembly) begins to arrest its fall. Among other things,maximum arrest force and belay system extension are mea-sured. The belay system may or may not be successful instopping the falling test block.5. Significance and Use5.1 The types of rope rescue systems to which this testmethod apply use a ten
23、sioned mainline and untensioned belayline. If a fall occurs because of a mainline system failure ormisuse, considerable energy must be absorbed by the belay fora successful arrest. This drop test method simulates a “worstcase” condition when systems are operated as designed, and isdesigned to help e
24、valuate and compare the performance ofvarious rope rescue belay systems under such conditions. (SeeNote 1.) The successful catching of a load does not imply thatthe tested system is suitable for any and all belaying. See X1.2.NOTE 1Higher forces may be encountered under some circumstances,such as th
25、e belay being operated with excessive slack.6. Interferences6.1 The method used to release the test block could affectthe results by imparting motion to the block, in addition to thestraight fall caused by gravity.6.1.1 Residual magnetism of an electromagnetic releaseshall be guarded against.6.1.2 T
26、he use of a light cord between the test block and thehoist line, which is cut by a heated nichrome wire or stickmounted knife, is also satisfactory.6.1.3 Any release buckle, latch, or device that might imparta sideways force to the suspended mass shall not be used.6.1.4 Any restriction imposed on th
27、e test block, such as theuse of guide rails to contain and control the blocks fall, or theuse of a linear motion transducer, shall be constructed andmaintained so that the combined effect shall not reduce thevelocity of the mass more than 2 % from the velocity of a freefalling block of similar mass.
28、 Velocity measurements shall bemade and recorded at the beginning of each test day whenguide rail type test rigs are to be used.6.2 If the lifting lines system uses a twisted cable, theremay be difficulties with the test block turning and twisting therope. This can be prevented by light “anti-twiste
29、r” cordsrunning off to the side of the block that are released at the sametime as the lifting line connection.6.3 Inconsistency in the tightening of knots shall beavoided.7. Apparatus7.1 The test facility shall be a structure with less than 1 mmof immediate elastic deformation at a force of 50 kN at
30、 theanchor point and having a natural frequency above 200 Hz.7.1.1 Failing this, a distinct cautionary note should be madein all reports generated at the test facility regarding the anchorrigidity or natural frequency.7.2 The test block shall have an appropriate mass and, ifmade from a collection of
31、 plates, bars, or ingots, shall be joinedin a fashion that prevents play or relative movement of partsduring the testing. It shall be provided with a shackle for theattachment of the belay line and the lifting line (through thequick-disconnect fitting) from which it hangs in symmetry. Theshackle sha
32、ll have less than 1 mm of immediate elasticdeformation at a force of 50 kN.7.2.1 The mass of the rigid test block shall be Type II (100kg), Type IV (200 kg), or Type V (280 kg) 6 1 %, includingattachment hardware, for the testing of equipment intended foruse with various rescue systems, in accordanc
33、e with Specifi-cation F2266. The user should select the most appropriate massto the intended application. Adequate attachment point,rigidity, and symmetry shall be maintained. The mass usedshall be included in the report.7.3 The belay line shall be tied directly to the test blockusing a bowline knot
34、. Use of a setup where the rope is tied toa platen (catch plate) upon which the falling test block impactsshall not be permitted.F2436 1427.4 The test block lifting system shall be able to position thetest block to a tolerance of 60.5 cm and when stopped, sustainthe test block for a 5 min period at
35、a given height with the sametolerance.7.4.1 The lifting line shall pass not more than 10 cmhorizontally in distance from the anchor point for the belayassembly.7.5 If a pit of loose material such as sand is used, careshould be taken so that the test block does not increase its massby picking up mate
36、rial from the pit after impact.7.6 For belay assemblies that require an active grippinghand for operation, an artificial hand shall be substituted toprevent staff injuries.7.6.1 The artificial hand shall be constructed as pictured inFig. 1.7.6.2 The artificial hand shall be spring pressure plates th
37、atprovide a constant belay rope tension. The user shall select theappropriate tension. See X1.3. The tension used shall beincluded in the report.FIG. 1 Artificial HandF2436 1437.6.3 When an artificial hand is used, it is considered to bean integral part of the belay assembly.7.6.4 Hanging a mass on
38、the belay rope in place of anartificial hand is not permitted.7.6.5 The point where the rope leaves the artificial hand(when required) shall be within 40 cm of the point where therope enters the belay assembly. There shall be no slack in therope between the artificial hand and the belay assembly.7.6
39、.6 Various anchor points for the artificial hand, each withan immediate elastic deformation of less than 1 mm under theapplication of a 500 N force, shall be provided so that theposition relative to the belay assembly can duplicate theposition of function in actual use.7.7 The test facility shall ha
40、ve a rope flaking area, whereadditional rope can be loosely flaked out. The test block shallbe able to reach the ground without using up this additionalrope.7.7.1 The flaking area shall be a flat horizontal surface onthe testing facility with no roughness or irregularities to impedethe free flow of
41、the rope.7.7.2 The rope (belay line) shall be flaked at an angle lessthan 15 of directly in line with the devices intended mannerof use for braking, and the flaking area shall be positioned toprovide1m(610 cm) of unsupported rope between the flakingarea and the belay device being tested.7.8 The maxi
42、mum arrest force (MAF) shall be measured bya system, which is accurate to 61 % of the MAF, free fromartifact, and whose calibration is traceable to a recognizedsource. It is preferable that the recording device also be able togenerate a force/time curve.7.8.1 MAF measurements are obtained by samplin
43、g of anelectronic load cell or other suitable device. Its physicalcharacteristics and all associated electronics shall allow sam-pling at a minimum of 2000 times per second. The minimumresonant frequency of the load cell shall be 4 kHz.7.9 To determine the belay extension, the lowest pointduring the
44、 drop shall be read by using a suitable device capableof measuring to an accuracy of 61 cm. Care shall be exercisedthat extension measuring system causes no significant cush-ioning or retarding effect on the test block. The total velocitydifference from a free falling mass and a mass with or without
45、guide rails and an extension measuring system shall be lessthan 2 %. The system used shall be clearly described andillustrated in the report.8. Safety Hazards8.1 PrecautionsThis test method involves a falling mass,moving rope, numerous possible pinch points, and the potentialfor flying debris if a c
46、omponent fails during a drop test. Avoidcontact with any of the test materials or the apparatus duringoperation and provide shielding for workers. Place hazardwarning signs in a conspicuous place. The development ofsafety procedures, both general and specific to the particulartest facility, is stron
47、gly recommended.8.2 Precautions should also be taken to protect anyinstrumentation, such as force transducers, electrical leads,distance measurement devices, and so forth, from possibledamage from rope snapback or flying debris in the event of afailed component during a drop test.9. Sampling9.1 If t
48、he belay assembly is intended for use on variousdiameters of ropes, tests shall be done on both the largest andsmallest and, if the range exceeds 2 mm, on representativediameters in between. If the belay assembly is intended for usewith various brands and designs of ropes, each rope brand andconstru
49、ction should be tested. (See Note 2.)NOTE 2Different rope brands of same diameter can have unexpecteddifferences in performance, apparently, due to fairly small differences inrope construction. It should be clearly stated which rope brands, sizes andconstructions were tested and the condition they were in at the start oftesting.10. Conditioning10.1 While different conditions of temperature and humiditymay affect impact forces and other test results, conditioning ofropes is not feasible for most testing. If conditioning is feasible,stan
