Helmet and brain injury - Lecture 19 Flashcards
Hockey helmet certification standard
-Construction and coverage
-shock absorption
-penetration
retention system properties (how well the helmet stays on the head)
-field of vision (measures how well you can see)
-marking and information (to prevent being sued)
Biomechanics of brain injury
Where you get hit matters
-side of the head is more vulnerable
Laurence of Arabia
aka T.E Lawrence
His motorcycle was a gift from his friend
George Bernard Shaw
Requirements and the corresponding test methods, where appropriate, are given for the following:
- Construction and coverage
- shock absorption
- penetration
- retention system properties
- field of vision
- marking and information.
Shock absorbing capacity
When tested in accordance with Clause 5.4, no single impact shall exceed a peak acceleration of 275g or 1500 GSI under all test conditions. The outer covering (shell) shall remain intact, with no cracks visible through its thickness.
Biomechanics of Brain Injury
- Accident events (sport) resulting in concussions: Falls, collisions, punches and projectiles.
- Impact Event Characteristics: Location, Velocity, Duration, Mass, Impact Direction.
- Dynamic Response Characteristics: linear acceleration, rotational acceleration, duration, direction of impact.
- Brain tissue trauma: strain, stress, pressure, strain rate.