ASTM F1446-2011 Standard Test Methods for Equipment and Procedures Used in Evaluating the Performance Characteristics of Protective Headgear.pdf

1、Designation: F1446 11An American National StandardStandard Test Methods forEquipment and Procedures Used in Evaluating thePerformance Characteristics of Protective Headgear1This standard is issued under the fixed designation F1446; the number immediately following the designation indicates the year

2、oforiginal adoption or, in the case of revision, 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.INTRODUCTIONThese test methods specify equipment and procedures used

3、for testing protective headgear.Individual ASTM performance standards (standard specifications) will use these procedures andequipment. Test conditions, pass-fail criteria, and other performance requirements will be specified inthe individual performance standards, tailored to the needs of a particu

4、lar activity (for example,bicycling, skateboarding, skiing, etc.).These test methods were developed using resources in medical, scientific, mechanical engineering,human factors, and biomechanical fields. However, it is recognized that it is not possible to write aprotective headgear performance stan

5、dard that will result in headgear that can protect against injuryor death in all accidents. It is also recognized that serious injury or death can result from both low-and high-energy impacts, even when protective headgear is worn.These test methods incorporate aspects of other recognized headgear p

6、erformance standards. Theydraw from work done by others where appropriate for these test methods. These standards arereferenced within this standard test method. It should be noted that these test methods specifylaboratory tests of completed headgear to measure its ability to reduce head acceleratio

7、n during useand other selected parameters.1. Scope1.1 These test methods cover laboratory equipment, proce-dures, and basic requirements pertinent to testing protectiveheadgear. Deviations or additions, or both, to these testmethods will be specified, as required, in individual ASTMperformance stand

8、ards.1.2 RequirementsThe protective headgear is to be testedunder specified environmental conditions for the following:1.2.1 Impact attenuation (the limiting of head acceleration)of the protective headgear, and1.2.2 Strength and stability of the retention system and itsattachment to the protective h

9、eadgear.1.2.3 Special tests for particular protective headgear useswill be specified in the individual performance standards to beused in conjunction with these test methods.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibil

10、ity of the user of this 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 Standard:2E177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE691 Practice for Conducti

11、ng an Interlaboratory Study toDetermine the Precision of a Test MethodF2220 Specification for Headforms2.2 Federal Motor Vehicle Safety Standard:3218 S7.1.8 Motorcycle Helmets2.3 SAE Standard:4SAE J211 Recommended Practice for Instrumentation for1These test methods are under the jurisdiction of ASTM

12、 Committee F08 onSports Equipment and Facilities and are the direct responsibility of SubcommitteeF08.53 on Headgear and Helmets.Current edition approved March 1, 2011. Published May 2011. Originallyapproved in 1993. Last previous edition approved in 2008 as F1446 08. DOI:10.1520/F1446-11.2For refer

13、enced 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 website.3Available from National Highway Traffic SafetyAdministration (NHTSA),

14、4007th St., NW, Washington, DC 20590.4Available from Society of Automotive Engineers (SAE), 400 CommonwealthDr., Warrendale, PA 15096-0001.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.Impact TestsRequirements for Channel Class 100

15、03. Reference Table3.1 For references to these test methods, the standard termsfor reference are listed in bold type in Table 1 with the items toconsider for each method. For conditions and anvils, use thestandard term listed in Table 1. Referring to section numbers inthese test methods is not the r

16、ecommended method for refer-ence.4. Terminology4.1 basic plane, nan anatomical plane (Frankfort Hori-zontal Plane) that includes the superior rim of the externalauditory meatus (upper edge of the external openings of theear) and the inferior margin of the orbit (the lowest point of thefloor of the e

17、ye socket). The headforms are marked with thebasic plane (see Figs. 1 and 2).4.2 coronal plane, nan anatomical plane perpendicular toboth the basic and midsagittal planes and passing through thesuperior rims of the right and left auditory meatuses. Thetransverse plane corresponds to the coronal plan

18、e (see Figs. 1and 2).4.3 field of vision, nangle of vision as measured on thereference headform (upward, downward, and peripheral).4.4 headform size selection, nhelmets shall be tested onthe appropriate test headform size(s), as determined by thetesting laboratory. Helmets shall be tested on the lar

19、gest andsmallest size test headforms on which they fit. If a smaller sizeof the same model fits the smaller headform, the larger helmetwill be tested on the larger headform only. When multipleheadform sizes are required, each test set of helmets willinclude at least one extent of coverage, vision te

20、st, retentiontest, and impact test on each specified headform size. “Fit”means that it is not physically difficult to put the helmet on thelarger headform and that the helmets comfort or fit-foam ispartially compressed on the smaller headform.4.5 helmet, na protective device worn on the head in anef

21、fort to reduce or minimize injury to that portion of the headthat is within an area above the test line (as defined in theindividual performance standards).4.6 helmet position index (HPI), nthe vertical distancefrom the brow of the helmet to the basic plane, when thehelmet is placed on a reference h

22、eadform. The manufacturershall specify the size of the headform and the vertical distance.4.7 midsagittal plane, nan anatomical plane perpendicu-lar to the basic plane and containing the midpoint of the lineconnecting the notches of the right and left inferior orbitalridges and the midpoint of the l

23、ine connecting the superior rimsTABLE 1 Table for ReferenceTerms for Reference Section Items to Consider for Each MethodChin Bar Rigidity 12.9 Types defined: impact velocity, nominal drop heightConditioning Environments 10 Types defined: ambient, low temperature, high temperature, waterimmersionConf

24、iguration 12.2 Standard requirement definedDynamic Retention Test 12.7.1 Types defined: mass of drop weight, drop height, extension pass/failcriteriaHeadforms 7.1 Headforms to be used in all tests in Test Methods F1446Impact Anvil 7.3.1 Types defined: flat, hemispherical, cylindrical, triangular haz

25、ard,curbstoneImpact Attenuation Test 12.8 Types defined: number of impact sites, impact velocity andtheoretical drop height, and maximum peak g valueInternal Projections 12.5.1 Standard requirement definedLabeling 12.4 Standard labeling requirements definedMaterials 12.3 Standard requirement defined

26、Peripheral Vision 12.6.1 Standard method of pass/fail for horizontal vision definedReference Marking 12.1 Standard method of marking defined, define test linesReporting 13 Standard report format definedRoll-Off Test (Helmet Stability Test) 12.7.2 Types defined: mass of drop weight, drop height, stan

27、dard methodof pass/fail definedSamples for Testing 8 Criteria to be considered in selecting number of samplesSelecting the Correct Headform 7.1.1 Method definedTest Schedule 11 Standard test schedule definedFIG. 1 Anatomical PlanesF1446 112of the right and left external auditory meatus. The longitud

28、inalplane corresponds to the midsagittal plane (see Figs. 1 and 2).4.8 modular elastomer programmer (MEP), nacylindrical-shaped pad used as the impact surface for thespherical impactor.4.9 preload ballast, na “bean-bag” filled with shot placedon the helmet to secure its position on the headform. The

29、weight of the preload ballast shall be 5.0 6 0.1 kg unlessotherwise specified in the individual performance specification.4.10 projection, nany part of a helmet, internal or exter-nal, that extends beyond the faired surface and is likely tocause injury.4.11 protective headgear, nsee helmet.4.12 refe

30、rence headforms, nmeasuring headforms con-toured in the same configuration as the test headforms sizes A,E, J, M, or O, as defined in Specification F2220. The referenceheadforms should include surface markings corresponding tothe basic, coronal, midsagittal, and reference planes (see Figs.1 and 2).4

31、.13 reference plane, na plane marked on the headformsat a specified distance above and parallel to the basic plane (seeFig. 3).4.14 retention system, nthe complete assembly that se-cures the helmet, in a stable position, on the wearers head.4.15 shield, noptional equipment used in place of gogglesto

32、 protect the eyes.4.16 spherical impactor, na device made of low reso-nance material (for example, magnesium), 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 spherica

33、llymachined impact face with a radius of 73 mm on its bottomsurface. All radii from the center of the curvature of the impactface to its outer edge shall from 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

34、center ofthe ball arm. The mass and center of gravity of the dropassembly including the impactor shall meet the same require-ments as those specified for the drop assembly incorporatedwith the test headforms (see 7.3.2).4.17 test area, nthe area of the helmet on or above aspecified test line, subjec

35、t to impact or penetration testing.4.18 test headforms, ntest headforms that correspond tothe physical dimensions defined in Specification F2220 as sizesA, E, J, M, and O. The weight of the drop assembly includingthe headform shall be 5.0 kg unless otherwise specified in theindividual performance sp

36、ecifications. The test headformsshould include surface markings corresponding to the basic,coronal, midsagittal, and reference planes (see Fig. 2).4.19 test line, na line drawn on the helmet as specified inthe individual performance standards.4.20 visor (peak), noptional equipment for protectionagai

37、nst sun or glare, and sometimes used as a rock or dirtdeflector.5. Significance and Use5.1 The purpose of these test methods is to provide reliableand repeatable tests for the evaluation of various types ofprotective headgear. Use of these test methods in conjunctionwith the specific individual perf

38、ormance standards is intendedto reduce the likelihood of serious injury and death resultingfrom impacts to the head sustained by individuals participatingin sports, recreation, and other leisure activities in whichprotective headgear is worn.6. Certification6.1 These test methods permit self-certifi

39、cation. It is recom-mended that each manufacturer employ an independent testlaboratory at least annually to test each model and size ofprotective headgear.7. Apparatus7.1 Test Headforms:7.1.1 GeneralThese test methods specify five headformsizes as identified in Specification F2220 (A, E, J, M, and O

40、)FIG. 2 Test HeadformBasic, Reference, and Midsagittal PlanesFIG. 3 Location of Reference LineF1446 113for performing reference measurements, impact, roll-off, dy-namic retention, penetration, and other tests required by theindividual performance specification standards.7.1.2 Impact HeadformsThese h

41、eadforms shall be madeof K1A magnesium material and shall conform to the externaldimension requirements of each particular headform size, asspecified in Specification F2220.7.1.3 Other HeadformsThese headforms should be madeof material of sufficient strength and stiffness to maintain theirgeometry d

42、uring testing. They shall conform to the externaldimension requirements of each particular headform size, asspecified in Specification F2220. Full-chin headforms will beused as necessary.7.2 Retention SystemThe test apparatus for the roll-offand dynamic retention testing are shown in Figs. 4 and 5re

43、spectively. The mass of the drop weight and drop height arespecified in the individual performance specification standards.7.2.1 Roll-Off Cable and HookA flexible strap or cableand attaching hook connect the guide rod to the far edge of thehelmet. The flexible strap or cable shall be of a material h

44、avingan elongation of no more than 18 mm/m when loaded with1000 N. The cable and hook shall weigh less than 200 g.7.2.2 Roll-Off Test ApparatusThe test apparatus shall beused to apply a shock load to a helmet secured to the headformby its own retention system. The geometry of the test headformshall

45、comply with the dimension of the full chin referenceheadforms. The headform shall be secured in a test fixture withits vertical axis pointing downward at 45 to the direction ofgravity (see Fig. 4). The test fixture shall permit rotation of theFIG. 4 Typical Apparatus for Roll-off (Stability) TestFIG

46、. 5 Typical Apparatus for Retention System Strength andExtension TestF1446 114headform about its vertical axis and include a means to lock theheadform in the face-up and face-down positions. The guiderod and hammer are similar to those in the dynamic retentionstrength test minus the simulated jawbon

47、e. This equipmentshall allow a drop weight to slide in a guided free fall to impacta rigid stop anvil. The guide shall weigh 0.9 to 1.4 kg.7.2.3 Dynamic Retention Test ApparatusThe retentionsystem test equipment shall allow a drop weight to slide in aguided free fall to impact a rigid stop anvil (se

48、e Fig. 5). Thegeometry of the test headform shall comply with the dimensionof the reference headforms. The headform shall be secured ina test fixture with its vertical axis pointing upward in thedirection of gravity (see Fig. 5). The guide rod and hammershall consist of a simulate jawbone, guide rod

49、 with stop, dropweight, and position measuring system(s). The entire dynamictest apparatus hangs freely on the retention system. The entiremass of the support assembly, excluding drop weight, must be7kg6 5%.7.2.3.1 Simulated Jaw BoneThis stirrup shall consist oftwo metal bars that spin freely, each with a diameter of 12.5 60.5 mm, that have a center distance of 76.0 6 1 mm.7.3 Impact AttenuationThe impact attenuation test appa-ratus shall allow determination of the impact attenuationcharacteristics of helmet (see Fig. 6).7.3.1 Impact AnvilsTh