REALLY stupid questions about hard hat diving

[Gary D.]

There is a “Non Return” valve that screws onto the back of the hat. The air hose attaches to that valve so any interruption in airflow is stopped there.

Should the air hose be disconnected for some reason it shuts down giving the diver around 7-10 minutes of air depending on how they are breathing.

The diver has control of his own air. They can shut it down so there is no exhaust or let it blow like a ruptured hose. He also has control of the exhaust which in combination with air in makes you light or heavy. There is a chin dump inside as well as the manual valve on the outside for exhaust.

If a diver was at EXTREAM depths and the air hose was disconnected, at or near the surface, the divers body could be squeezed into the helmet and even up the hose.

The reason for this is the diver is being squeezed by the ambient pressure while the hose end is at the surface pressure. Like an air compressor or air tank. Air in the tank is at higher pressure that the surrounding air. Open the valve and the air escapes. Now if you’re inside any obstruction wants to come out.

The suit is NOT pressurized. The diver is experiencing the same pressures as a SCUBA diver. Now if your considering the air coming in to over ride the water pressure so the suit can be kept from squeezing the diver it is. But it is an ambient pressure suit just like a SCUBA dry suit.

Another thing to remember about them is, unlike scuba, the hat is connected to the suit. If your feet stink you’re going to smell them. If you spit out some liquid your feet are getting wet.

Very different diving than SCUBA, but in many ways still very similar.

Gary D.

 

[vertaqua]

A couple of things I think people missed, the reason the hats are made of metal or nowadays fiberglass is mainly for head protection. Remember your not down there to sightsee, your there to work. Sometimes things could be dropped(wrenches, bolts prybars) from the boat or barge your working from. They do make a soft helmet called a band mask that is basically a surfaced supplied full face mask with a neopene hood. However these ar only used for inspections/ light work.

Also commercial divers still wear hard hats some still use the MK5 rig, most divers however use a fiberglass or ligter brass helmet. They weigh about 30lbs and can be worn with a wetsuit or connected up to a drysuit.

 

[Ron Brandt]

Can you tell I watched "Men of Honor" tonight?

Just of the topic of the suit and on to that movie...I had the honor of being on a movie set last year for three days as a safty diver. The Director of Photography was
Anthony B. Richmond the same director of photography of Men of Honor. We talked and guess what we talked about?

Diving......He also mentioned he had a lot of fun working on Men of Honor.:14:


Ron

 

[Gary D.]

A couple of things I think people missed, the reason the hats are made of metal or nowadays fiberglass is mainly for head protection. Remember your not down there to sightsee, your there to work. Sometimes things could be dropped(wrenches, bolts prybars) from the boat or barge your working from. They do make a soft helmet called a band mask that is basically a surfaced supplied full face mask with a neopene hood. However these ar only used for inspections/ light work.

Also commercial divers still wear hard hats some still use the MK5 rig, most divers however use a fiberglass or ligter brass helmet. They weigh about 30lbs and can be worn with a wetsuit or connected up to a drysuit.

The metal hats, like the MK-5 and others and the newer hats, like the MK-17 are two different breeds which aren't really related.

I have already explained above how the metal hats work. The newer hats are totally different in that they seal around your neck and not the suit. Air ONLY goes into the hat and not the suit as the others do. That creats some problems and at the same time eliminates other problems.

The soft ones are full face masks and nothing more. Even with a soft hood attached, with or without a spider, they are still a full face mask.

Keep in mind that Men of Honor is a movie. There was a lot of factual stuff in it as well as a lot of Hollywood production.

Gary D.