A pattern of two breaths per diver should be established as soon as possible and then terminate the dive and start the ascent as soon as possible, as air consumption while buddy breathing is usually more than double the normal rate. Most demand valves will only drain correctly if the hose is to the user's right, and in these cases the divers should align themselves to allow convenient movement of the demand valve from donor to recipient and back. When the divers need to ascend or swim horizontally, it requires co-ordination and some skill, which is best practiced in a low hazard environment.