1、Designation: F429 10An American National StandardStandard Test Method forShock-Attenuation Characteristics of Protective Headgearfor Football1This standard is issued under the fixed designation F429; the number immediately following the designation indicates the year of originaladoption or, in the c
2、ase of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.Asuperscriptepsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the determination of the shock-attenuation characteristics of protect
3、ive headgear for football.21.2 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this
4、 standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:3F717 Specification for Football Helmets2.2 SAE Document:J221 JUN 80 Instrumentation for Impact Tests, Require-ments for C
5、hannel Class 100042.3 ISO Standard:ISO/DIS 6220 Headforms For Use in the Testing of Protec-tive Helmets53. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 basic planean anatomical plane that includes thesuperior rims of the auditory meatuses (the upper edges of theexternal openin
6、gs of the ears) and the notches of the inferiororbital ridges (the bottom of the eye sockets). See Fig. 1.3.1.2 coronal planea vertical plane that is perpendicularto the median and reference planes and passes through thecrown of the headform (lateral plane).3.1.3 crowna point in the median plane whi
7、ch is equalchord lengths from the anterior and posterior intersections ofthe median and reference planes.3.1.4 drop heightthe vertical distance between the lowestpoint (impact point) of the elevated helmet and the apex of theimpact surface.3.1.5 gdimensionless ratio of the acceleration of theheadfor
8、m during impact to the acceleration due to gravity.3.1.6 gmaxthe maximum value of g encountered duringimpact.3.1.7 median planea vertical plane that passes through theheadform from front to back and divides it into right and lefthalves (mid-sagittal plane).3.1.8 protective headgearthe assembled devi
9、ce and ac-cessories as supplied by the manufacturer primarily intended toprotect the wearers head while participating in football.3.1.9 reference planea plane that is located at a specifieddistance above and parallel to the basic plane.1This test method is under the jurisdiction of ASTM Committee F0
10、8 on SportsEquipment and Facilities and is the direct responsibility of Subcommittee F08.53 onHeadgear and Helmets.Current edition approved Aug. 1, 2010. Published September 2010. Originallyapproved in 1975. Last previous edition approved in 2007 as F429 01 (2007).DOI: 10.1520/F0429-10.2Performance
11、requirements for football helmets are found in Specification F717.3For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM web
12、site.4Available from the Society of Automotive Engineers, 400 Commonwealth Dr.,Warrendale, PA 15096.5Available from American National Standards Institute, 11 W. 42nd St., 13thFloor, New York, NY 10036.FIG. 1 ISO HeadformBasic, Reference, and Median Planes1Copyright ASTM International, 100 Barr Harbo
13、r Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4. Summary of Test Method4.1 Aheadgear is mounted on a headform that is oriented indifferent positions and is dropped at a specific velocity onto animpact surface.Alinear accelerometer mounted at the center ofgravity of the headfo
14、rm monitors the acceleration and the timehistory of impact which are recorded with appropriate instru-mentation.5. Significance and Use5.1 Maximum acceleration and time duration data obtainedby the specified procedures are intended to determine the shockattenuation characteristics of a headgear.NOTE
15、 1These data can be used at a later date to assess the protectionafforded to the head when blows are delivered to the helmet.6. Apparatus56.1 Guide Assembly6The headform shall be attached tothe free-fall drop assembly carriage by an adjustable mountingwhich will allow impacts to be delivered to any
16、prescribedpoint on the helmet (see Fig. 2). The carriage shall be free toslide on vertical guides. If wires are used they must be placedunder at least 845-N tension (see 12.4 for guide assemblyspecifications and allowable weight of drop assembly).6.2 Recording Equipment6The recording equipment shall
17、meet the following criteria:6.2.1 Acceleration TransducerThe acceleration trans-ducer is mounted at the center of gravity of the combined testheadform and carriage assembly with the sensitive axis alignedto within 5 of the vertical when the helmet and headform arein the impact position. The accelera
18、tion data channel complieswith SAE Recommended Practice J211 JUN 80 (a low passfilter having a 4-pole Butterworth transfer function and acorner frequency of 1650 Hz meets this requirement). Digitalfiltering at 1650 Hz can be substituted.6.2.2 System AccuracyThe impact recording system shallbe capabl
19、e of measuring shocks of up to 500-g peak accelera-tion with an accuracy of 6 5%.6.2.3 Impact RecordingThe impact shall be recorded onsingle- or dual-trace storage oscilloscope with 0.1-mV to 20-Vdeflection factor, 1 to 5-ms sweep speed-division, and 500-kHzbandwidth.6.2.4 HeadformsStandard headform
20、s as described in 12.4will be used for helmet impact testing.6.2.5 Height Measuring RodAmetal rod accurate to 62.5mm shall be used for measuring drop heights.6.2.6 Impact SurfacesThe impact surface for the instru-ment system check (see Section 10) shall be a flat, ModularElastomer Programmer (MEP),6
21、152 mm in diameter and 25mm in thickness. The MEP shall have a durometer of 60 6 2Shore “A.” The MEP is mounted on an aluminum mountingplate with a minimum thickness of 5.59 mm after grinding. TheMEP (including aluminum mounting plate) shall be firmlyaffixed to the top surface of a flat metal anvil.
22、 The base shallconsist of a rigid slab weighing at least 136 kg. For helmetimpacts, the instrument system check MEP is replaced with aMEP 13 mm in thickness, 152 mm in diameter, and adurometer of 38 6 5 Shore “A.”6.2.7 Spherical Impactor6 A device made of low reso-nance material, for example, magnes
23、ium, aluminum alloy orstainless steel, that couples mechanically with the ball armconnector of the drop assembly in place of the impact testheadform. When mounted, the device presents a sphericallymachined impact face with a radius of 73 mm on its bottomsurface. All radii from the center of curvatur
24、e of the impactface to its outer edge shall form angles of no less than 40 withthe downward vertical axis. The center of curvature shall bewithin 5 mm of the vertical axis drawn through the center ofthe ball arm. The mass of the drop assembly including theimpactor shall meet the same requirements as
25、 those specifiedfor the drop assembly incorporated with the test headforms (seesection 12.4).7. Sampling7.1 Submit at least three specimen helmets, one for testunder the various conditions as described in Section 11.6The sole source of supply of the apparatus known to the committee at this timeis the Research or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).F429 105
