Retention system

Retention system is the complete assembly that secures the helmet in a stable position on the wearer's head.

Source

16 CFR § 1203.4


Scoping language

Basic plane means an anatomical plane that includes the auditory meatuses (the external ear openings) and the inferior orbital rims (the bottom edges of the eye sockets). The ISO headforms are marked with a plane corresponding to this basic plane (see Figures 1 and 2 of this part).

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