Auto send email timeouts

Hi there

I have a script that send out emails to specific email addresses held
in a csv file which goes something along the lines of:

parse csv file for email conent
for each csv line{
if (data check meets requirements){
send the email(data)
}
}

ok, there are lots of checks, formatting & so on.

Now, this does work they way it is expected to do so, until the number
of emails to send exceeds the time out limit.

I have used set_time_limit(xxx) to set the timeout to the server
limit, but this is only delaying the problem.

Ideally I would like to have the script just keep going until it has
reached the end of the csv file, no matter if it takes 1 minutes or 20
minutes to do so.

Does anyone have any ideas where to start such a thing?

Thank you for your help
Ice