In cases such as the Flash Crash and the failure of Facebook shares to launch for public trading smoothly, exchanges need to “come together” to prevent repeats of breakdowns, said the top technology officer of BATS Global Markets.

"Clearly we need to come together and help fix the market" in cases like this, said Chris Isaacson, the chief technology officer for BATS.

He was referring to the delayed opening of Facebook shares a month ago and failure by the Nasdaq Stock Market to confirm orders placed that morning on its crossing system for the initial offering. The disruption of that much-watched IPO, themost visible and highly subscribed of the year, gave the industry a black eye.

Isaacson suggested that the listing market, in this case Nasdaq, give all exchanges an “all-clear” warning, before continuous trading in new shares begins. Typically, he noted, the greatest amount of liquidity comes from the listing market and if it’s not functioning properly, orderly trading will be affected.

BATS had its own technical disruption that prevented its own shares from going public this year. Opening of trading in BATS shares, listed on its own BATS Exchange, was delayed and a software bug impaired pricing and trading of its shares.

BATS decided to halt trading, he said, on March 23 because trading would not be orderly.

Bryan Harkins, the chief operating officer of the Direct Edge exchanges, suggested a “hot line” be put in place to bring together exchange operators in time of crisis to address a market-wide problem jointly.

“Our main job is to be stewards of investor confidence," he said. “ The Faceboook disruption represented “a major lesson learned," in that regard.

While not recommending a recurrence, “sometimes, you need a May 6 type of event to force the industry to come up with a market-wide contingency plan,’’ said Joe Mecane, Executive Vice President and Co-Head of U.S. Listing and Cash Execution at NYSE Euronext.

Eric Noll, Executive Vice President, of Transaction Services U.S., for Nasdaq OMX Group, originally was scheduled to participate on the panel, but did not.