ASTM F429-2001(2007) Standard Test Method for Shock-Attenuation Characteristics of Protective Headgear for Football《橄榄球运动用防护头盔的减冲击性能的标准试验方法》.pdf

1、Designation: F 429 01 (Reapproved 2007)An American National StandardStandard Test Method forShock-Attenuation Characteristics of Protective Headgearfor Football1This standard is issued under the fixed designation F 429; the number immediately following the designation indicates the year oforiginal a

2、doption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the determination of the shock-attenuation c

3、haracteristics of protective headgear for football.21.2 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 standard to establish appro-priate safety and health practices and determine the applica-bility of

4、 regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:3F 717 Specification for Football Helmets2.2 SAE Document:J221 JUN 80 Instrumentation for Impact Tests, Require-ments for Channel Class 100042.3 ISO Standard:ISO/DIS 6220 Headforms For Use in the Testing of Protec-tive He

5、lmets53. 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 openings of the ears) and the notches of the inferiororbital ridges (the bottom of the eye sockets). See

6、 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 which is equalchord lengths from the anterior and posterior intersections ofthe median and reference

7、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 theheadform during impact to the acceleration due to gravity.3.1.6 gmaxthe maximum value of g encountered du

8、ringimpact.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 device and ac-cessories as supplied by the manufacturer primarily intended toprotect the wearers head

9、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 F08 on SportsEquipment and Facilities and is the direct responsibility of Subcommittee F08.53 onHead

10、gear and Helmets.Current edition approved May 1, 2007. Published August 2007. Originallyapproved in 1975. Last previous edition approved in 2001 as F 429 01.2Performance requirements for football helmets are found in SpecificationF 717.3For referenced ASTM standards, visit the ASTM website, www.astm

11、.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.4Available from the Society of Automotive Engineers, 400 Commonwealth Dr.,Warrendale, PA 15096.5Available from American Natio

12、nal Standards Institute, 11 W. 42nd St., 13thFloor, New York, NY 10036.FIG. 1 ISO HeadformBasic, Reference, and Median Planes1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4. Summary of Test Method4.1 Aheadgear is mounted on a headf

13、orm that is oriented indifferent positions and is dropped at a specific velocity onto animpact surface.Alinear accelerometer mounted at the center ofgravity of the headform monitors the acceleration and the timehistory of impact which are recorded with appropriate instru-mentation.5. Significance an

14、d Use5.1 Maximum acceleration and time duration data obtainedby the specified procedures are intended to determine the shockattenuation characteristics of a headgear.NOTE 1These data can be used at a later date to assess the protectionafforded to the head when blows are delivered to the helmet.6. Ap

15、paratus56.1 Guide Assembly6The headform shall be attached tothe free-fall drop assembly carriage by an adjustable mountingwhich will allow impacts to be delivered to any prescribedpoint on the helmet (see Fig. 2). The carriage shall be free toslide on vertical guides. If wires are used they must be

16、placedunder at least 190-lbf (845-N) tension (see 12.4 for guideassembly specifications and allowable weight of drop assem-bly).6.2 Recording Equipment6The recording equipment shallmeet the following criteria:6.2.1 Acceleration TransducerThe acceleration trans-ducer is mounted at the center of gravi

17、ty 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 acceleration data channel complieswith SAE Recommended Practice J211 JUN 80 (a low passfilter having a 4-pole Butterworth trans

18、fer 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 capable of measuring shocks of up to 500- g peakacceleration with an accuracy of 6 5%.6.2.3 Impact RecordingThe impact shall

19、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 headforms as described in 12.4will be used for helmet impact testing.6.2.5 Height Measuring RodA metal rod accurate to 60.10 in.

20、 (6 2.5 mm) 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),6152 mm in diameter and 25mm in thickness. The MEP shall have a durometer of 60 6 2Shore “A.” The MEP is m

21、ounted on an aluminum mountingplate with a minimum thickness of 0.220 in. after grinding. TheMEP (including aluminum mounting plate) shall be firmlyaffixed to the top surface of a flat metal anvil. The base shallconsist of a rigid slab weighing at least 136 kg. For helmetimpacts, the instrument syst

22、em 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, magnesium, aluminum alloy orstainless steel, that couples mechanically with the ball armconnector of the drop

23、 assembly in place of the impact testheadform. When mounted, the device presents a sphericallymachined impact face with a radius of 2.875 in. (73 mm) on itsbottom surface. All radii from the center of curvature of theimpact face to its outer edge shall form angles of no less than40 with the downward

24、 vertical axis. The center of curvatureshall be within 5 mm of the vertical axis drawn through thecenter of the ball arm.The mass of the drop assembly includingthe impactor shall meet the same requirements as thosespecified for the drop assembly incorporated with the testheadforms (see section 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).F 429 01 (2007)5