BS EN 960:2006 pdf download

BS EN 960:2006 pdf download.Headforms for use in the testing of protective helmets.
Partly because of the impossibility of assigning these smaller heads code letters less than A (the other end of the alphabet was considered and disrrwssed), it was decided to abandon the code letter system of identification. Further, the concept of internal circumference of a helmet’ was removed. Instead, headfomis have now been classified only according to a size designation, which corresponds to their circumference.
During this revision the opportunity Wd5 taken to correct obvious errors present in the existing tab4es. which evidence themselves on the headforrns as spurious bumps and depressons. Also, the data points were smoothed where obvious discontinuities occurred and the protruding chin was removed
Whilst. ideally, the dimensions of headforms already in existence, which satisfy’ EN 960:1994, should comply with the dimensions given in this revision, because of the preceding paragraph, there are a few points which fall outside of the tolerances specified.
The spherical coordinates of head sizes 445 to 645 are given in the normative Annex A. The equations, which define the radii of the spherical coordinates in terms of headform circunilerence and vertical and horizontal angles, ace given in the informative Annex B.
The first international draft standard for headforms was ISOIR151 1:1970, followed many years later by ISO1DIS 6220:1983. Both of these documents were based upon the British Standard, BS 1869:1960, which Itself was developed from the first set of test headlorms produced by the UK Transport and Road Research laboratory in the 1950s. The TRRL headlorms were designated solely by their size, given in inches. The increment between each size was one eighth of an inch
During the drafting of BS 1869, the concept of code letters was introduced, but unfortunately, errors of transposition from the TRRL data were made, which resulted in incorrect dimensions being specified and the Inclusion of headform code letter H, circumference 565 mm. This headfomi was also specified In R151 1. but subsequently dropped from ISOIDIS 6220 and EN 960:1994. The dimensional errors however, were carried forward through R151 1, ISO/DIS 6220 and EN 960:1994.
A summary of this brief history is tabulated in informative Annex C.
li) a facility (or attaching an accelerometer shall be incorporated within the headform or its means of support, such that, with the headform in any angular orientation, the respective sensitive axes of the accelerometer shall pass within 10mm of point A.
NOTE 1 For this type of test, full and three-quarter headforms may be specified in the respective helmet standard. NOTE 2 The geometry ol the half headforrn does not facihiale Its use for this type of test.
NOTE 3 Care should be taken to ensure that the total mass of the headform, when fitted with the accelerometer and its means of attachment, rails within any tolerances specified in either this standard or the respective helmet standard, as appropriate
3.1.2 Headforms for shock absorption and penetration tests, with rigidly mounted (not falling) headformlhelmet assembly
The headforms shall be made of a ngid material which does not affect the measurements of shock absorption or penetration (e.g. wood). The headforms, together with their means of support, shall exhibit no resonance below a frequency o12 000 Hz.
NOTE For this type of lest, fua, three-quarter and half headforms may be specified lithe respective heitnet standard.
3.1.3 Headfocrns for geometric examination or positional marking of the helmet
The headforms shall be made of any suitable materiaL
3.1.4 Headforms for other tests
When a test requires the headform to be made from a specific material or to possess s(,eciflc material characteristics (e.g. thermal or electncal conductivity, thermal capacity etc.). these materials and characteristics shall be as speafied in the relevant helmet standard.
3.2 Dimensions
The outer surface of each headtorm shall lie within the locus of the coordinates given in Annex A. Between
coordinate points, the outer surface of the headfom’i shall be curved and smooth.
NOTE The exact geometry of the swface between the specified coordinates may be determined, for example, by a 3” spliw fiaidion.
3.3 Marking
3.3.1 Headfomis for geometric examination or positional marking of the helmet shall be marked with:
a) size designation of the headlorm:
b) reference plane;
C) basic plane;
d) vertical longitudinal plane;
e) vertical transverse plane.
3.3.2 All other headforms shall be marked, at least, witti the size designation of the headform.
NOTE Other marking may be required by specific helmet standards.