OSL's websites says:

"If you wish the search to be carried out by a person of your own gender, please inform the security officer."

http://www.osl.no/en/osl/baggageandc...ty_Checkpoint/


I am guessing that Europeans are less concerned with these gender issues than Americans are, so they figure that providing this option is sufficient. Similarly, Europe also has more co-ed hostel rooms and nude beaches than the US.