EN 14052-2012 pdf download.High performance industrial helmets.
6.3.2 Selection of size
Five size designations of headfomi are specified for use in this European Standard, 495, 535, 575. 605 and 625 (EN 960:2006 — these are equivalent to codes A, E, J, M and 0, respectively, EN 960:1994).
Helmets shall be tested on the headforms of appropriate size (from size designations 495. 535, 575, 605 and 625), as selected by adjusting any size adjustment facility of the helmet to the largest size and the smallest size of its adjustment range.
6.4 Shock absorption
The procedures specified in EN 13087-2 shall be employed.
In addition, the following pre-requisites apply:
a) for crown impacts, the falling mass method with the hemispherical striker shall be used;
b) for off-crown impacts, the falling mass method with the hemispherical striker shall also be used, but with the modifications given in 6.4 C) and e) below;
c) the guidance system shall provide only guided fall. Free fall is not permitted. A single axis accelerometer shall be firmly attached to the striker and arranged so that its sensitive axis coincides with the vertical axis passing through the central vertical axis of the headforrn when erect and the central vertical axis of the striker, The accelerometer shall be capable of withstanding a maximum deceleration of 5 000 g without damage. The headform shall be rigidly mounted at the required angle of inclination, such that the axis of the striker passes through the point G of the full headform or point A of the % headform (see EN 960:2006). The rigidity of the headform mounting shall be deemed to be adequate if, when the appropriate validation test detailed in 6.4 e) is performed, the maximum deceleration measured for the inclined headform is within 10 % of that obtained for the erect headiorm assembly;
d) the headforms shall be either full headlorms (typically mounted by the base of the neck) or % headforrns (typically mounted on a centrally located ball joint arrangement). In either case, the shape of the headform shall comply with the relevant clauses of EN 960:2006 (size designations 495, 535, 575, 605, 625). In the case of % headforms, additional means shall be provided to secure the chinstrap of a helmet (if provided) in the manner intended by the helmet manufacturer. For the off.crown impacts, the headforrn shall be able to be inclined at least at angles of 15°, 30°. 45°, and 60° to the vertical;
e) in the validation test for each of the two headforms assemblies an MEP (modular elastomeric programmer) or similar interface (to protect the headforrn) shall be filled to the striker carriage, instead of the hemispherical striker element. An impact shall be made on to the erect headform assembly to give a nominal deceleration of 300 g. A further impact, using the same parameters, shall be made on to the inclined headform assembly at 60° to the vertical. The two deceleratioris shall be compared. For the assembly that incorporates the ¼ headform the comparison tests are to be conducted with the headform orientated in such a way that in the two tests the striker impacts the same site on it. For the assembly that incorporates the full headform the comparison tests are to be conducted with a dummy headform that has the same contour at the point of impact for both the headform erect and headfocm inclined configurations;
NOTE 1 A spherical radius of nominally 65 mm. would be suitable for the dummy headfomi. This would present an impact surface with a contour approximating that of the top of a size A headlorm.
f) there shall be two impacts per helmet and two helmets per condition. There shall be one impact on the crown of the helmet and one off-crown impact The axis of impact shall pass through point G of the full headiorm (see EN 960:2006) or point A of the ¼ headfom, (see EN 960:2006). The off-crown sites shall be determined by the angle of inclination of the headform’s central vertical axis about point G (or point A). The headform inclination shall be between 15 and 60° to the vertical;
g) the impact energy for crown impacts shall be (100,0 ± 0.5) J. The impact energy for off-crown impacts shall be (50,0 ± 0.25) J. Impact sites shall be separated by no less than 75 mm,
h) the impact site for off-crown impacts shall be at a different point on each of the eight helmets tested under the mandatory conditioning (hot, cold, wet, artificial ageing);
NOTE 2 For example: front, left side, rear and tight side.
I) the impact site for off-crown impacts shall include at least one impact at 60° to the vertical, and
one impact as close as possible to the crown.
6.5 Resistance to penetration
The procedure specified in EN 13087-3 using the flat blade striker shall be employed, except that the mass of the flat blade striker shall be (1 000 ± 15) g.
In addition, the following pre-requisites apply:
a) two impacts per helmet, two helmets per condition;
b) on each helmet, one impact on the crown plus one impact at any one other site, This other site shall be between 15° and 60° to the verticaL The axis of impact shall pass through point G of the headform;EN 14052-2012 pdf download.