1、Designation: F2821 10F2821 15Standard Test Methods forBasket Type Rescue Litters1This standard is issued under the fixed designation F2821; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in pare
2、ntheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 These test methods will enable the user to determine if a rescue litter meets theirthe requirement for strength depending upontheir particular applic
3、ations and methods of use.1.2 The test methods described in this standard are designed to test several parameters under “manner of use” conditions.1.3 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversionsto inch-pound units that ar
4、e provided for information only and are not considered standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the appli
5、cability of regulatorylimitations prior to use.2. Terminology2.1 Definitions of Terms Specific to This Standard:2.1.1 basket type litter, na conveyance for the sick or injured usually consisting of a tubular metal frame enclosing a moldedplastic or wire shell. Also known as a basket stretcher.2.1.2
6、litter bridle, na manufactured or improvised system that attaches the litter to the raising or lowering system.2.1.3 horizontal lift, nrefers to the patient being in a horizontal position with the head and feet at approximately the samelevel. In this configuration the litter bridle attaches to the l
7、itter at four points.2.1.4 anchor plate, na device installed inside the litter that is used to attach the litter to the bed of the test apparatus. It mustbe of sufficient size and stiffness to distribute the forces on the litter shell or frame, thereby allowing the test of the attachmentpoints.point
8、s2.1.5 vertical lift, nrefers to the patient being in a head up and feet down position. In this configuration the litter bridle attachesto the litter at the head end only.3. Summary of Test Method3.1 Horizontal test method is designed to test the litter attachment points and the resistance of the li
9、tter to folding or curling.3.2 Vertical test method is designed to test the structural strength of the head end of the litter or the manufacturers designatedbridle attachment points or both, and for a two-piece litter, to also test the connection between the two sections of the litter.3.3 These test
10、s are destructive in nature and will require a new litter for each test.4. Significance and Use4.1 These test methods are intended to provide reproducible data from which acceptance criteria, design data, and specificationscan be developed for basket type rescue litters.5. Apparatus5.1 GeneralUse ca
11、librated electronic load measuring devices. The testing equipment shall have sufficient capacity to preventyielding of its components under the anticipated ultimate load, and shall have sufficient stiffness to ensure that the applied tensionloads remain parallel to the axis of the anchors.1 These te
12、st methods are under the jurisdiction of ASTM Committee F32 on Search and Rescue and are the direct responsibility of Subcommittee F32.01 on Equipment,Testing, and Maintenance.Current edition approved May 1, 2010Dec. 1, 2015. Published June 2010February 2016. Originally approved in 2010. Last previo
13、us edition approved in 2010 asF2821 10. DOI: 10.1520/F2821-10.10.1520/F2821-15.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequat
14、ely depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken
15、, PA 19428-2959. United States15.2 Anchor Plate(if used) Shall be installed in the litter in such a way that the force distributes equally and does notconcentrate on a single element. The purpose is to test the attachment points of the litter bridle, the connection points that holdthe halves of two-
16、piece litter together, and the litters ability to resist folding or bending both longitudinally and laterally. Theanchor plate size must be kept to a minimum so that it does not provide any increased resistance to the litter bending during a test.In cases where the litter does not have a frame, the
17、plate shall span any ribs or other structural elements within the shell in orderthat the forces are distributed over a wide enough area that unintentional damage does not occur.5.3 Sample OrientationThe litter subject to test can be loaded either horizontally or vertically depending upon the testapp
18、aratus being used.6. Hazards6.1 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations pr
19、ior to use.6.2 These tests are destructive in nature and there is the potential for injury from flying objects that are ejected during the tests.The person performing the tests shall wear appropriate safety equipment, the test apparatus shall be properly guarded, and the testsshall not be performed
20、alone.7. Procedure for Horizontal Litter Test7.1 Attach a 4 leg litter bridle to the litter at points designated by the litter manufacturer. Each individual bridle leg shall be ofa fixed length.7.1.1 The bridle shall be constructed of chain or cable 9.5-mm (38to -in.) cable. If using cable, the indi
21、vidually terminated bridlelegs shall be proof loaded to a force of 1.5 kN (350 lbf) pre-litter test to eliminate stretching or the potential for any adjuster buckleslippage or both.slippage during the litter test.7.1.2 The internal angle of the bridle legs attached to the head and foot ends of the l
22、itter shall be 90 6 2.litter bridleconfiguration shall allow the suspended litter to be at zero degrees to the horizontal 65.7.2 Rest the litter on a uniform surface (floor). Measure and record the height from the reference surface to the top of the toplitter rail of the litter assembly at the same
23、relative location 60.5 cm (2 6 0.2 in.) that the litter bridle used for testing is attached.This measurement shall take place at all four litter bridle connection points.7.3 Secure the litter to the bed of the test machine using an anchor plate of approximately 40 by 40 cm (16 by 16 in.) insidethe l
24、itter. The plate shall be centered in a manner that allows the litter to maintain a level orientation to the horizontal, betweenthe rails and ends of the litter, and shall span at least two rails (or ribs) and cross rails (or ribs) to distribute the forces in the litter.In cases where the litter doe
25、s not have a frame, or if the specified plate size does not span the frame rails, the size can be increasedto span structural elements in the shell or the frame. In the event that the plate comes into contact with the side elements, the platemay be narrowed accordingly to eliminate interference.7.3.
26、1 The anchor plate shall have an integral center connection point. It is recommended that this attachment point have theability to swivel independent of the anchor plate.7.3.2 The anchor plate shall be connected to a suitable anchorage point on the text fixture or floor using chain or cable allowing
27、for a vertically straight pull.7.3.3 Reconfirm that the litter is at 0 6 5 to the horizontal.7.4 Apply a pulling force of 11kn (2,473 lbf) to the bridle at the rate of 30 6 2.5 cm (12 6 1 in.) a minute. The test concludeswhen any part of the litter fails or when any part of a structural element is d
28、eformed more than 560.5 cm (260.2 in.).per minute.7.4.1 Failure of the litter prior to reaching the prescribed force shall constitute a failure.7.4.2 After the load specified in 7.4 has been applied and released, remove the litter from the test apparatus and situate on thesame uniform surface. Repea
29、t the measurements at the same locations. Permanent deformation of the top rail or part of the mainstructural elements in excess of 5 6 0.5 cm (2 6 0.2 in.) shall constitute a failure.8. Procedure for Vertical Litter Test8.1 Rest the litter on a uniform surface (floor). Measure and record the overal
30、l length and width of the top litter rail of the litterassembly, 60.5 cm ( 0.2 in.).8.2 Attach test apparatus to the head end of the litter at points designated by the litter manufacturer. If the litter is equipped withdesignated connection points then those connection points shall be used. If the m
31、anufacturer suggests that the litter be attached witha system using rope or webbing wrapped around the frame rails, then those instructions shall be followed.8.2.1 The bridle shall be constructed of chain or cable 9.5 mm (38to in.) cable. If using cable, the individually terminated bridlelegs shall
32、be proof loaded to a force of 1.5 kN (350 lbf) pre-litter test to eliminate stretching or the potential for any adjuster buckleslippage or both.slippage during the litter test. If rope or webbing is used it shall be of sufficient strength to minimize elongationand to insure that the litter is tested
33、 and not the attachment method or material.F2821 1528.3 The internal angle of the bridle shall be as small as possible. If manufactured connections on the litter are in such a locationthat the bridle contacts the shell of the litter, the bridle shall be extended just enough to eliminate contact with
34、 the litter shell.8.4 Secure the litter to the bed of the test machine using an anchor plate of approximately 40 by 40 cm (16 by 16 in.) insidethe litter. The plate shall be centered between the rails (or ribs) at the end of the litter opposite of the bridle. The plate shall spanany rails or cross r
35、ails to distribute the load on the litter frame or shell. In cases where the litter does not have a frame, or if thespecified plate size does not span the frame rails, the size can be increased to span structural elements in the shell or the frame.In the event that the plate comes into contact with
36、the side elements, the plate may be narrowed accordingly to eliminateinterference.8.5 Apply a pulling force of 11kN (2,473 lbf) to the bridle at the rate of 30 6 2.5 cm (12 6 1 in.) a minute. The test concludeswhen any part of the litter fails or when any part of a structural element is deformed mor
37、e than 5 6 0.5 cm (2 6 0.2 in.)per minute.8.5.1 Failure of the litter prior to reaching the prescribed force shall constitute a failure.8.5.2 Upon reaching the specified pulling force, release the load and return the litter to the uniform surface. Record the overalllength and width of the top litter
38、 rail of the assembly 5 6 0.5 cm (2 6 0.2 in.). Permanent deformation is the difference betweenthe final litter measurements and initial litter measurements. Permanent deformation of the top litter rail or part of the mainstructural elements in excess of 5 6 0.5 cm (2 6 0.2 in.). shall constitute a
39、failure.9. Report9.1 Report the force on the litter at the time any structural element fails to the nearest 0.1 kN (23 lbf).9.2 Report the amount of permanent deformation of any structural element to the nearest 0.5 cm (0.2 in.).9.3 Report the force on the litter at the time any structural element f
40、ails or the deformation of any structural element exceeds5 60.5 cm (2 6 0.2 in.). Report the attachment points used, location of the failure, the dimensions of the bridle before and afterthe test, the internal angle of the bridle before and after the test, and any special concerns observed.10. Preci
41、sion and Bias10.1 Insufficient information is currently available to characterize the precision and bias Precision of the test method describedhere. As the test method is more widely used, the precision and bias will be characterized.procedures can be affected bydissymmetry in individual bridle leg
42、length resulting in one section seeing higher loads than others.11. Keywords11.1 lifting bridle; rescue litter; rescue stretcher; stretcherAPPENDIX(Nonmandatory Information)X1. Sample Test SetupsX1.1 Horizontal Litter TestX1.1.1 Fig. X1.1 shows a suggested schematic of a test setup. The key point to
43、 remember is that the reaction plate shall be largeenough to span frame members or structural elements in the shell but not so large as to inhibit bending or curling of the frame,especially on the horizontal test.X1.2 Vertical Litter TestX1.2.1 Fig. X1.2 shows the bridle attached to a frame down tub
44、e but depending upon the litter and the manufacturers instructionsit may be connected to designated attachment points or other locations on the frame.F2821 153This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revis
45、ed, either reapproved or withdrawn.Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may
46、attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United State
47、s. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ X1.1 Schematic of Test SetupFIG. X1.2 Bridle Attached to a Frame Down TubeF2821 154
