Random testing of food items by Seven Sharp for traces of shellfish has returned 100 per cent negative results, a big relief for people with a shellfish allergy.
Martin Dickson has a life-threatening allergy to shellfish and has come close to dying due to cross-contamination.
He told the programme he discovered a note on a hot chicken saying it may contain traces of crustaceans and wondered "how do you get prawns in a chicken?"
Mr Dickson said there can also be cross contamination of "crackers, chips, chicken stock, onion soup that you put in the old fashioned dip. Cross contamination by oil is obviously a really big thing".
For the experiment, Seven Sharp targeted eight food outlets along one stretch of road for lunch food, reporter Carolyn Robinson pretending to have a shellfish allergy.
She said two of the shops couldn't guarantee her a safe meal and were really careful to let her know, so she left them.
Items from the other six were taken to a lab for testing for traces of crustaceans.
A burger, sandwich, brownie, salad, curry and fries - plus some supermarket cooked chicken - all came back negative for shellfish.
Mr Dickson says when eating out he's always careful to explain he has a severe allergy, and he wants restaurants to have accurate information on whether food contains shellfish.
Earlier this month, Delmaine had to recall a batch of its fresh chicken chowder amid fears it might contain hoki and mussels.
Testing food for different allergens of late, Seven Sharp found four out of the seven supposedly dairy-free items tested contained milk.
But there was a 100 per cent pass rate on traces of peanuts.
The programme will be testing for other allergens.