After a motorcycle helmet has sustained a significant impact in a crash or a hard drop onto concrete, what should be done with it?

1. Repaint the scratched area and continue using it indefinitely
2. Replace it immediately, as the internal EPS impact-absorbing liner crushes permanently upon first impact
3. Soak it in hot soapy water to restore the crushed foam
4. Use it for another 10 years as long as the outer shell shows no visible cracks