Chicago-based Cboe Global Markets, Inc. will close its trading floor and shift to all-electronic trading after Friday.

Following a similar move by CME Global, Chicago’s other major derivatives exchange, Cboe said it will temporarily close the Cboe Options Exchange trading floor “as a precautionary measure” to prevent the potential spread of Covid-19.

The exchange said that the suspension of open outcry trading is preventative and not due to any confirmed positive tests for the virus.

“Cboe is closely monitoring developments around Covid-19 and is following guidance provided by governmental and public health agencies to evaluate reopening of its trading floor,” it said.

Trading will be electronic-only until further notice.