The safety assessment process FAQs
Learn how SHARP tests helmets, including impact scenarios, methods, and how results are evaluated.
SHARP appears to be mainly concerned with linear impacts, isn’t rotational acceleration also very important?
Yes. SHARP includes a test for rotational acceleration in the same way that UN-ECE Regulation does. Detailed information about these tests and how they relate to real world road accidents can be found in the report ‘Technical Response to the Unpublished Paper by NJ Mills‘ which can be found in the SHARP library section of this website.
Why do you only strike helmets once in each impact site when some standards strike the same site twice?
We do not have any evidence to suggest that in a motorcycle crash, helmets suffer repeated impacts on the same site. However, real world data does tell us that helmets can receive multiple impacts in a crash, and that is why the SHARP assessment does involve more than one impact on a single helmet, but at different points.
Why does SHARP carry out impact tests at specific points on a helmet?
The kind of brain injury that can happen in a crash depends on what part of your head is bashed inside the helmet. To ensure that we accurately assess helmet performance, it is important that our impact conditions are representative of real-world crashes. The in-depth investigations into crashes carried out by COST 327 confirmed a direct correlation between the location of damage to a helmet and head injury. It considered the UN-ECE Regulation impact locations to be appropriate and SHARP therefore uses the same impact points – to the front, rear, crown, left and right sides.
In addition to this however, for every helmet model that is rated, a sample is dismantled to check whether there is any localised reinforcement that could lead to an inappropriately high rating. If this is considered likely, SHARP retains the right to test at any other point on the helmet (within the extent of protection specified in Annex 4 to UN-ECE Regulation 22.05).
How does SHARP assess the chin bar?
SHARP makes no assessment of the chin bar that covers the lower half of the face, only the locking system to keep it in place. We believe the mandatory chin bar assessment of the British Standard or UN-ECE Regulation 22.05 and 22.06 are adequate – we have no measure by which we can objectively rate their safety beyond compliance with these requirements. We do however check each helmet that we assess to ensure that these tests have been conducted, given that Regulation 22.06 approvals can be given to a full-face helmet even when the chin bar has not been shown to satisfy the specific chin bar requirements. When we find this case, we indicate it on our website by use of a helmet symbol having a red cross over the chin bar.
