The stock market nosedived on Monday, Feb. 5. The Dow Jones Industrial Average dropped 1,175 points, or 4.6%, in its largest single-day point drop ever. The S&P 500 declined 4.1% and the Nasdaq tumbled 3.8%. 

These are the details you need to know about trading halts put in place to protect against market crashes. 

Per NYSE Rule 80B, a 15-minute circuit-breaker trading halt kicks in for a Level 1 decline when the S&P 500 falls 7% before 3:25 p.m. EST. In the case of an early scheduled close, the decline has to take place before 12:25 p.m. EST.

A Level 2 decline occurs when the S&P 500 falls 13% during that time frame -- it also results in a 15-minute trading halt. A Level 3 decline requires a 20% fall on the S&P 500 -- in that case, trading would be halted for the remainder of the day.

A Level 1 or Level 2 halt can only occur once per trading day, according to the NYSE's rules. 

"For example, following the reopening of trading after a Level 1 Market Decline halt, the NYSE would not halt the market again unless a Level 2 Market Decline was to occur. Likewise, following the reopening of trading after a Level 2 Market Decline, the NYSE would not halt trading again unless a Level 3 Market Decline were to occur, at which point, trading in all stocks would be halted until the primary market opens the next trading day," the exchange writes. 

More from Stocks

Lotteries Are for Losers: Kick the Habit and Become a Millionaire

Lotteries Are for Losers: Kick the Habit and Become a Millionaire

Bearish Bets: 2 Well-Known Stocks You Should Consider Shorting This Week

Bearish Bets: 2 Well-Known Stocks You Should Consider Shorting This Week

Alphabet's Waymo Is Moving Toward Self-Driving Semi Trucks

Alphabet's Waymo Is Moving Toward Self-Driving Semi Trucks

This 'Modern' Stock Market Needs to Change

This 'Modern' Stock Market Needs to Change

What to Expect From the Markets in 2019 According to an Abbott Downing Executive

What to Expect From the Markets in 2019 According to an Abbott Downing Executive