Divers, alpha flag, US flag & DSMBs

[wonkywinch]

I learned to scuba dive this year and as a yottie already familiar with the alpha flag and the US red with white diagonal.

What I'd never seen before my PADI course but been using a lot this week is a DSMB. For those who don't dive, basically an inflatable red/orange/pink post about a metre high that you launch from about 5m below whilst you do your safety stop prior to surfacing.

I'd never seen one before and none of my RYA material for sailing or power mentions what it is.

I'm not sure I've ever seen one whilst sailing but would have certainly avoided it if I'd seen one but it got me wondering if the RYA shouldn't be including this important signal being used by other water users?

 

[ctva]

Whilst I suppose it shouldn’t surprise me that the Americans have a different ‘diver down’ flag, I’ve never seen it before or knew of its use.

Why are the Americans different to the rest of the world?

As to the marker, there are so many types that swimmers use, that most generally know they mean someone in the water.

 

[Boathook]

I've seen divers in shallow water have a float, normally orange, attached to indicate their position.

 

[LiftyK]

Good point. I sail and I dive but never noticed the lack of mention of a delayed surface marker buoy in sailing training. As our coast is surrounded by wrecks, I’m surprised I don’t see the inflatable buoys more often.

 

[B27]

Generally DSMBs occur close to support boats flying A flags.
Common enough around Swanage, Portland etc.
Swimmers towing floats are often seen around the coast.

The US Diver Down flag was of course an album cover for Van Halen.

 

[MontyMariner]

Even back when I learned to dive in '72, SMB's were coming in so that the pickup boat could keep track of the divers.
Over the years sport diving has changed, almost out of recognition with mixed gas diving!
For some types of diving I can see that a DSMB would be a good idea but for an average grot around in 20m from a boat, a flagged SMB is still good. Part of the safety boats duties is to ward off approaching boats.

 

[Alicatt]

As above, deployed as you are getting up to your safety stop, also used orange floats as a surface marker especially when doing drift dives where you are letting the current/tide carry you along so the safety boat can keep track of where you are

 

[michael_w]

Several years ago, heading east past St Adlhelm's Head, we came across a couple of divers on the surface. Their safety boat was nowhere to be seen. They had deployed one of those inflatable markers and were waving it about.

Cue for a rapid spinnaker douse and head back to see if we could help. As we got near, their dopey safety boat noticed and came hurtling over to pick them up.

 

[capnsensible]

Whilst I suppose it shouldn’t surprise me that the Americans have a different ‘diver down’ flag, I’ve never seen it before or knew of its use.

Why are the Americans different to the rest of the world?

As to the marker, there are so many types that swimmers use, that most generally know they mean someone in the water.

All over the Caribbean. Loadsa dive schools everywhere too.

 

[wonkywinch]

Search for any diving related floats, flags, patches etc and they all seem to use the red with white line flag. An instructor told me the alpha flag is for boats, the red/white for actual diver in water location but I've not seen a reference for that.

 

[vyv_cox]

The red and white flag is used exclusively in the eastern Mediterranean and even as far west as Mallorca.

 

[Ammonite]

I learned to scuba dive this year and as a yottie already familiar with the alpha flag and the US red with white diagonal.
View attachment 185601
What I'd never seen before my PADI course but been using a lot this week is a DSMB. For those who don't dive, basically an inflatable red/orange/pink post about a metre high that you launch from about 5m below whilst you do your safety stop prior to surfacing.

I'd never seen one before and none of my RYA material for sailing or power mentions what it is.

I'm not sure I've ever seen one whilst sailing but would have certainly avoided it if I'd seen one but it got me wondering if the RYA shouldn't be including this important signal being used by other water users?

View attachment 185602

In most situations you are better off deploying this type of SMB while on the seabed as its much harder to control your buoyancy during a safety stop and you risk getting dragged upwards. It also lets the boat know where you are before you drift away from the wreck, reef etc in the tide.