239. Killing methods currently in use are: exsanguination without prior stunning, manual percussive stunning, with or without subsequent bleeding, and carbon dioxide narcosis followed by exsanguination. The chosen method of killing is at present dictated by a variety of factors including the volume of fish being handled and different demands on fish farmers by their customers. This latter factor may include details of how fish should be handled and slaughtered and whether or not they should be bled. However, there is an increasing awareness in the industry of the need to ensure that slaughter takes place under humane conditions and that fish should be stunned prior to slaughter by a method which causes immediate loss of consciousness which lasts until death.