;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;;;;Chat clear;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;;;;;;;;;;;;;;;;;;;;;;;; by xbox_gamer1;;;;;
on *:TEXT:!chatclear:#:{
if ($nick isop #) {
msg $chan /clear
msg $chan $nick Has Cleared the chatroom!
else { .notice $nick you are not authorized to use this command } halt
}

i beleive that should do it or you could add a user list to it and have one person set in it at first so they can add the people they want using it to the user list