How is a false start penalised?

Q: How is a false start penalised?

Under World Athletics TR 16.8 and 16.9, except in combined events, any athlete responsible for a false start is disqualified by the starter. There's no warning first. The starter's assistant raises a red and black (diagonally halved) card in front of the athlete. If lane markers allow it, the matching indication is shown on the lane marker. When one athlete false starts, others often follow. Only the athlete or athletes who, in the starter's opinion, were responsible are disqualified, which can be more than one athlete. If a recalled or aborted start wasn't caused by any athlete, no warnings are given and a green card is shown to all athletes. The starter or any recaller who thinks a start wasn't fair (including blocks slipping or something interfering with an athlete) must recall the athletes with a gun or other audible signal. ASA's domestic rules don't add a separate false start rule for youth age groups.

Question

Accepted Answer

Under World Athletics TR 16.8 and 16.9, except in combined events, any athlete responsible for a false start is disqualified by the starter. There's no warning first.

The starter's assistant raises a red and black (diagonally halved) card in front of the athlete. If lane markers allow it, the matching indication is shown on the lane marker.
When one athlete false starts, others often follow. Only the athlete or athletes who, in the starter's opinion, were responsible are disqualified, which can be more than one athlete.
If a recalled or aborted start wasn't caused by any athlete, no warnings are given and a green card is shown to all athletes.

The starter or any recaller who thinks a start wasn't fair (including blocks slipping or something interfering with an athlete) must recall the athletes with a gun or other audible signal.

ASA's domestic rules don't add a separate false start rule for youth age groups.