surface marker buoy (SMB) throughout the dive. This allows the boat to follow the group effectively in most conditions. If any of the divers need to surface early they can ascend on the SMB line, and surface at the buoy, which is where they will be most easily seen by the boat crew. If anyone is separated from the group they can deploy a DSMB to notify the boat thet they will be surfacing away from the float. Recovery of divers Divers may be picked up by a small tender or the dive boat may have a low enough freeboard for divers to climb over the side unaided, or with a bit of assistance from the crew. In this case it is usual to pass up heavy equipment such as weightbelts, and leave on the fins to help boost the diver out of the water. This is easiest with inflatable boats, particularly if provided with conveniently sited handles or ropes along the sides. For higher freeboards and easier boarding, mechanical aids may be provided: Ladders may be provided for boarding from the water.It is easier to climb a standard ladder or stairs if fins are removed first. They can be handed up to an attendant on the boat, clipped to the diver's harness, or carried by sliding the fin straps over the forearm. Christmas tree ladders can be climbed with the fins on the feet, and should stand off the side of the boat far enough for the fins to have clearance. Stern and side platforms may be used in conjunction with ladders or low freeboard decks. Passerelles or gangways are ramps which are lowered at one end to provide a path to walk from the deck to a dock or tender, and can also be used to walk to the water level. Diver lifts are platforms attached to the boat on which the diver stands while being lifted to deck level or lowered a short distance into the water. Stages and baskets are platforms which are lowered into and under the water and are hoisted back on board with the diver or divers standing on them. They are not attached to the boat except by the lifting cable. Boarding stirrups can be used on low freeboard boats, particularly rigid hull inflatables. They are straps with a loop, rung or hook at the lower end attached to the side of