The Mariner Lounge at Hammad International Airport is operated by Qatar Airways for the benefit of its seafarer and offshore passengers.
Seafarers or offshore workers may avail of the lounge's amenities while they are in transit and waiting for their connecting flight to the final destination or when signing off from the vessel or a rig. All passengers need to do is present a Qatar Airways boarding pass for the connecting flight as well as valid identification or a supporting document that will confirm passenger's eligibility as a seafarer or offshore crew.
Check out this document for the frequently asked questions about the Mariner Lounge.