1、Designation: F1446 12 An 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 partic
4、ular 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 sta
5、ndard 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
6、performance 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 accelerati
7、on during useand other selected parameters.1. Scope1.1 These test methods cover laboratory equipment,procedures, and basic requirements pertinent to testing protec-tive headgear. Deviations or additions, or both, to these testmethods will be specified, as required, in individual ASTMperformance stan
8、dards.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
9、headgear.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 theresponsibi
10、lity 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 Conduct
11、ing 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 forImpact TestsRequirements for Channel Class 10001These
12、 test methods are under the jurisdiction of ASTM Committee F08 onSports Equipment, Playing Surfaces, and Facilities and are the direct responsibilityof Subcommittee F08.53 on Headgear and Helmets.Current edition approved Nov. 15, 2012. Published January 2013. Originallyapproved in 1993. Last previou
13、s edition approved in 2011 as F1446 11a. DOI:10.1520/F1446-12.2For 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 website
14、.3Available from National Highway Traffic SafetyAdministration (NHTSA), 4007th St., NW, Washington, DC 20590.4Available from Society of Automotive Engineers (SAE), 400 CommonwealthDr., Warrendale, PA 15096-0001.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 1
15、9428-2959. United States13. 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 t
16、est methods is not the recommended method for refer-ence.4. Terminology4.1 Definitions:4.1.1 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 or
17、bit (the lowest point of thefloor of the eye socket). The headforms are marked with thebasic plane (see Figs. 1 and 2).4.1.2 coronal plane, nan anatomical plane perpendicularto both the basic and midsagittal planes and passing throughthe superior rims of the right and left auditory meatuses. Thetran
18、sverse plane corresponds to the coronal plane (see Figs. 1and 2).4.1.3 field of vision, nangle of vision as measured on thereference headform (upward, downward, and peripheral).4.1.4 headform size selection, nhelmets shall be tested onthe appropriate test headform size(s), as determined by thetestin
19、g laboratory. Helmets shall be tested on the largest andsmallest size test headforms on which they fit. When multipleheadform sizes are required, each test set of helmets willinclude at least one extent of coverage, vision test, retentiontest, and impact test on each specified headform size. “Fit”me
20、ans 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.4.1.5 helmet, na protective device worn on the head in aneffort to reduce or minimize injury to that portion of the headthat is with
21、in an area above the test line (as defined in theindividual performance standards).4.1.6 helmet position index (HPI), nthe vertical distancefrom the brow of the helmet to the basic plane, when thehelmet is placed on a reference headform. The manufacturershall specify the size of the headform and the
22、 vertical distance.4.1.7 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 line connecting the superior rimsof the right and left external audito
23、ry meatus. The longitudinalplane corresponds to the midsagittal plane (see Figs. 1 and 2).TABLE 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: ambi
24、ent, low temperature, high temperature, waterimmersionConfiguration 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
25、 defined: flat, hemispherical, cylindrical, triangular hazard, curb-stoneImpact Attenuation Test 12.8 Types defined: number of impact sites, impact velocity and theoreticaldrop height, and maximum peak g valueInternal Projections 12.5.1 Standard requirement definedLabeling 12.4 Standard labeling req
26、uirements definedMaterials 12.3 Standard requirement definedPeripheral 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)
27、12.7.2 Types defined: mass of drop weight, drop height, standard method ofpass/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 122
28、4.1.8 modular elastomer programmer (MEP), nacylindrical-shaped pad used as the impact surface for thespherical impactor.4.1.9 preload ballast, na “bean-bag” filled with shotplaced on the helmet to secure its position on the headform.The weight of the preload ballast shall be 5.0 6 0.1 kg unlessother
29、wise specified in the individual performance specification.4.1.10 projection, nany part of a helmet, internal orexternal, that extends beyond the faired surface and is likely tocause injury.4.1.11 protective headgear, nsee helmet.4.1.12 reference headforms, nmeasuring headforms con-toured in the sam
30、e configuration as the test headforms sizes A,C, E, J, M, and O, as defined in Specification F2220. Thereference headforms should include surface markings corre-sponding to the basic, coronal, midsagittal, and referenceplanes (see Figs. 1 and 2).4.1.13 reference plane, na plane marked on the headfor
31、msat a specified distance above and parallel to the basic plane (seeFig. 3).4.1.14 retention system, nthe complete assembly thatsecures the helmet, in a stable position, on the wearers head.4.1.15 shield, noptional equipment used in place ofgoggles to protect the eyes.4.1.16 spherical impactor, na d
32、evice 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 sphericallymachined impact face with a radius of 73 mm
33、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 center ofthe ball arm. The mass and center of g
34、ravity 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).4.1.17 test area, nthe area of the helmet on or above aspecified test line, subject to impact or penetration testing.4.1.18 tes
35、t headforms, ntest headforms that correspond tothe physical dimensions defined in Specification F2220 as sizesA, C, E, J, M, and O. The weight of the drop assemblyincluding the headform shall be 5.0 6 0.10 kg unless a variablemass drop assembly configuration is specified. If a variablemass configura
36、tion is specified, then the weight of the dropassembly shall comply with the weight specifications presentedin Table 2. The test headforms may include surface markingscorresponding to the basic, coronal, midsagittal, and referenceplanes (see Fig. Fig. 2).4.1.19 test line, na line drawn on the helmet
37、 as specifiedin the individual performance standards.4.1.20 visor (peak), noptional equipment for protectionagainst sun or glare, and sometimes used as a rock or dirtdeflector.FIG. 2 Test HeadformBasic, Reference, and Midsagittal PlanesHeadformLabelSize Designa-tion(circumference,mm)X,mm Y,mm Z,mmA
38、495 23.5 89.7 11.1C 515 24.5 92.7 11.5E 535 25.5 96.0 11.9J 575 27.5 102.4 12.7M 605 29.0 107.2 13.3O 625 30.0 110.2 13.7FIG. 3 Location of Reference LineTABLE 2 Test Headforms and Mass Specifications for VariableMass Drop Assembly ConfigurationHeadform Label Size Designation Drop Assembly MassA 495
39、 mm 3.1 0.10 kgC 515 mm 3.6 0.10 kgE 535 mm 4.1 0.12 kgJ 575 mm 4.7 0.14 kgM 605 mm 5.6 0.16 kgO 625 mm 6.1 0.18 kgF1446 1235. 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
40、test methods in conjunctionwith the specific individual performance 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 wor
41、n.6. Certification6.1 These test methods permit self-certification. 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 six headformsi
42、zes as identified in Specification F2220 (A, C, E, J, M, and O)for performing reference measurements, impact, roll-off, dy-namic retention, penetration, and other tests required by theindividual performance specification standards.7.1.2 Impact HeadformsThese headforms shall be madeof K1A magnesium m
43、aterial 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 during testing. They shall conform to the
44、 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-off anddynamic retention testing are shown in Figs. 4 and 5 respec-tively. The mass of the drop weigh
45、t 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 havingan elongation of no more than 18
46、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 comply with the dimension of the full
47、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 theheadform about its vertical axis and include a means to lock theheadform in the face-up and fac
48、e-down positions. The guiderod and hammer are similar to those in the dynamic retentionstrength test minus the simulated jawbone. This equipmentFIG. 4 Typical Apparatus for Roll-off (Stability) TestF1446 124shall allow a drop weight to slide in a guided free fall to impacta rigid stop anvil. The gui
49、de 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 (see 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 with stop, dropweight, and position measuring sy
