Deploying an SMB From Depth: Why, When and What Goes Wrong

You're at your first stop. In open water. No line, no bottom, no wall.

A boat engine gets louder.

Does the boat know you're there? Does your team have anything to hold a stop against besides their own buoyancy?

That's why the buoy goes up before you do.

Why deploy an SMB from depth?

Sending the buoy up before the ascent, not at the surface, does three things:

• It marks your position for the whole ascent, so a boat knows divers are coming up underneath.
• It gives the team a visual reference while you hold your stops in open water.
• It lets a live boat follow the team on a drift dive.

It's part of the exit. And like the rest of the exit, it's planned before the dive. See How to Plan a Dive: Start With the Exit.

What do you need?

UTD's minimum equipment is an SMB and a spool with at least 70 feet of line. We carry 100 feet. Stow it where you can reach it without rolling, and rig the buoy on the spool before the dive.

Use a spool, not a reel. A spool is small, has almost nothing to jam and can be dropped instantly. Reels belong to guideline work, where you need long lengths of line.

Who deploys, and when?

The dive plan decides. In UTD's pre-dive plan, the team names a leader who leads the ascent and deploys the SMB. The others hold position close by and watch.

On a drift dive with a live boat, the team may send the buoy up before leaving the bottom. On other dives, it usually goes up at or before the first stop. Agree on it in the briefing, not at depth.

What does a good deployment look like?

Unhurried. The deploying diver is neutral, horizontal and stable before touching the buoy. The team is set. The line stays clear of everyone's gear. The buoy goes up, the diver stays put, and the team starts its ascent together.

Simple to describe. Not simple to do while holding a stop in mid-water. That's why it's taught and practiced in the water, not learned here.

How do deployments go wrong?

Every one of those is a control or team problem, not an equipment problem. The fix is practice, with an instructor watching, until the deployment looks boring.

Here's the reality check.

The comfortable belief: I've shot a buoy before. It's easy.

The truth: it's easy when you're on the bottom with your knees down. In mid-water, holding a stop, with a team waiting, it's a skill.

Learn it properly

Our SMB Extension is built around this one skill. SMB deployment is also part of Essentials of Recreational Diving. For how the team supports the deployer, see Team Diving vs Buddy Diving.

Can you deploy your buoy in mid-water without moving a foot? How do you know?