An IRC server will automatically kill a connection if the client fails to respond to the ping message, so no need for the channel manager to worry about that. People that are set to "away" will be reported as such by the server when whoissed. So truth be told I really can't think of a reason why you'd need to ping people in this instance.

If you *really* want to ping people you could use ctcp ping as implemented on top of the irc protocol. Most clients will respond to these pings, although some might not, that's the downside.