Seeing as they eliminated the 80A collar rule, and short uptick rule right before all of this occured (since their thorough research demonstrated it would have absolutely no effect on volatility), I'm surprised to see if they still even have circuit breakers in place. Welcome to the second biggest one day drop since 87 (at least on S&P) and you can say you lived through it (hopefully).
"In the event of a 3600-POINT decline in the DJIA (30 percent), regardless of the time, MARKET CLOSES for the day." **Tip: Go Long if Dow drops ~3500 points in one day.