erc-accidental-paste-threshold-seconds

erc-accidental-paste-threshold-seconds is a variable defined in `erc.el'.
Its value is

nil

Documentation:
Minimum time, in seconds, before sending new lines via IRC.
If the value is a number, `erc-send-current-line' signals an error
if its previous invocation was fewer than this many seconds ago.
This is useful so that if you accidentally enter large amounts of text
into the ERC buffer, that text is not sent to the IRC server.

If the value is nil, `erc-send-current-line' always considers any
submitted line to be intentional.

You can customize this variable.

This variable was introduced, or its default value was changed, in version 24.4 of Emacs.