Swansea lost the second leg of their Europa League play-off 2-1, but a healthy first-leg advantage ensured they prevailed 6-3 on aggregate to set up group stage meetings with Valencia, Kuban Krasnodar and St Gallen.
During the game, a green light from a laser pen could be seen on Tremmel on several occasions when Petrolul had a set-piece near the Swansea goal.
It is not the first time a Premier League side has faced similar problems in Romania; Chelsea's Frank Lampard and David Luiz were also targeted during their Europa League last-16 tie against Steaua Bucharest in March.
"I wouldn't want to say people should be banned for it, but something like this should not happen," said the 34-year-old German.
"It should not be in the stadium. UEFA need to find some way to deal with it, whatever that is. It is meant to be a football game, not a laser shooting game."
But he believes it should be possible to identify those responsible for using the banned devices through video footage.
"It has not really happened to me before, maybe once or twice," he added.
"It seems like it is getting more popular over the last few years, but people are being found out because you have so many cameras in stadiums.
"You can see who does it and you get charged for it, simple as that.
"It has never happened to me in the Premier League because the supporters know they would be caught and charged."
Tremmel believes he was being targeted by more than one fan, and admitted it had an effect on his ability to keep his focus on the game.
He said: "I think there were two or three different ones, from both stands. Once it hits your eyes you just can't see anything. They are powerful.
"I would see them flash across and then it would hit directly. It was bad. Obviously as soon as you move it stops because they would have to be pretty sharp to keep up with you moving. But it is in your head.
"You are trying to organise your defence at a corner, but you notice it happening and it is distracting. It is annoying as you are trying to concentrate."