Sport Diving Vs. Professional Diving
I thought I would make a post explaining the differences of both Sport Diving and Professional Commercial Diving. There is a huge difference between them. I am not going into extreme detail but enough so that the average person will understand the use of the equipment and practices. First I guess I should tell a little about my background so as to you know where this information derives from. In my younger days I had a Dive Shop in the Florida Keys for years. In the Sport Diving area, I am a Licensed SCUBA Instructor, Dive Master, Dive Rescue, Search & Recovery and a Professional Speer Fisherman. I also held a United States Coast Guard Captains License for Ocean going Vessels. In my Professional Diving Background, I’m a Certified Commercial Deep Sea Diver, Saturation Deep Diving Systems, Underwater Burning (Cutting), NDT (Non-Destructive Testing) along with ROV’s (Remote Operaterated Vehicles) and Hyperbaric Medicine.
I should start off by explaining a little Physics. In diving we talk about Atmospheres. 1 Atmosphere is equal to 14.7 PSI. This is very important in keeping track of our depths due to the amount of pressure and the types of gases that we are breathing because they react differently as the pressure changes as you will see. For every 33 feet of depth in Saltwater is one Atmosphere, so at 99 feet deep were at 3 atmospheres and have 44.10 PSI around our body. You can also calculate per foot of water also, such as in Seawater the calculation is .445 PSI in Fresh Water its .447 PSI
If you hold your breath while snorkeling, you can dive down and come back up with no problem, if your breathing compressed gas (air) if you dive down and hold your breath, you will explode your lungs, get an embolism maybe even a subcutaneous embolism (Skin Tissues) This is very common. Or you could die. If I take a balloon that has been filled with 1 cubic foot of ambient air, if I take it down under water to 33 foot (1 Atmosphere it will decrease in size to half. If I bring the same balloon back to the surface the balloon is back to its original shape of having 1 cubic foot of air, this is how your lungs work. Now if I fill a balloon under water using compressed air to 1 cubic foot, then I slowly come to the surface the balloon will double its size and have 2 cubic feet of air inside. If you did this with your lungs and did not exhale your lungs would explode, but by breathing constantly while coming to the surface your lungs will be fine.
Ok, there are some major differences between the two areas of Diving. There is snorkeling which is mainly taken place on top of the water allowing you to view the undersea world making brief trips to the bottom if you so wish using a mask, snorkel weight belt and fins.
Then you also have Free Diving which also just use the natural atmospheric air, another words you just take a deep breathe and dive deep. You can find all kind of records in this sport, it is VERY Dangerous. You take the chance of shallow water black out, this is due to a large buildup of CO2 in your body which will result in drowning, this happens allot.
Then you have Speer fishing is done without tanks and uses “Free Diving” to shoot their fish. You snorkel on top of the water, pick out your fish and dive down to 130-150 feet using special types of fins which are about 3 feet long, shooting the fish then ascending back to the surface for another breath of air.
Then you have SCUBA Diving which is limited to 130 feet of depth using SCUBA (Self Contained Breathing Apparatus). This is due to breathing “Air” under pressure. The make up of the air that we breath is 21% O2 (Oxygen), 78% Nitrogen and 1 % varies rare gases such as Argon, Neon, etc. Have you ever wondered why CPR works? We as Humans only use a small percentage of the O2 that we breathe, this allows an excess of O2 be exhaled. That means there is still good O2 we breath out with every breath, this is why CRP works.
Lets take a quick look at the gases on an individual bases. Pure 100% Oxygen is used in burn victims to help re-oxygenate the damaged tissues. Most large Hospitals have Hyperbaric facilities on site to help treat burn victims, they insert them inside a Hyperbaric chamber under pressure then have them breath 100% oxygen for a predetermined amount of time. We call this treatment they follow are called “Medical Tables” that are used in the Industry to “treat” certain types of Diving related problems. It was the Deep Sea Diving Industry that gave the tech to the Hospitals to treat Burn victims.
In the Commercial Diving Industry we have to treat ourselves. This is manly due to most Doctors are not familiar with Diving related injuries and therefore don’t know the correct treatment or have the facilities to do so. The best Hyperbaric Facility in the Nation is at Duke University where over the last 60 years have been working with the Navy in the development and experimentation of Diving related injuries and the treatment their of.
There is a problem with 100% Oxygen, it cannot be breathed under extreme pressures, the molecular make up of Oxygen changes under pressure which is poisonous to us Humans. So, your wondering how do we dive at extreme depths if O2 turns to poison, we use small amounts in our breathing mixture. This reduces the poisonous nature of the gas but still allows our tissues to be oxygenated.
Nitrogen like I stated above takes up 78% of the air that we breath. Now you ask, so what does it do? It does very little but provide an inert carrier for the oxygen to get to our tissues. But allot of other inert gases could do the same thing, but in Nature the largest is Nitrogen. The only problem we run in to by using Nitrogen is when we put ourselves under extreme pressures, then the Nitrogen also changes at a molecular structure and it ends up becoming “toxic” as we breath it under pressure. Most of you have heard the term Nitrogen Narcosis. This is the term when diving breathing air at depths starting around 100 feet and deeper, you get the sensation of getting high or Narc’d. Now there is a way to lesson the narcotic effects of Nitrogen on the body by making bounce dives at a gradual deeper. Thus building up and having better motor control. I want to state that this is VERY Dangerous in SCUBA Diving. You should NEVER go deeper than 130 feet always monitoring your bottom time.
I am not a big fan of the Dive computers, I’m old school, I remember when they came out. Orca was the first to market one for sport diving industry. The problem with diving computers use a base line for calculations for 10 tissue samples. The problems with this is it does not take into account what you ate, what you drank your weight, body fat, etc. I don’t like anything that would tend people to “PUSH” the limits, when you do this, bad things happen.
There is also Cave Diving, which is also very popular from where I’m from in Florida. It is also very dangerous unless thoroughly trained on how to do it along with the specialized equipment that is used.
Then we move in to a very specialized area of diving which is very close to the Commercial Diving realm as you will see. I’m talking about re-breathers. This is a piece of equipment that was first designed and developed for the NAVY in the Spec Op community. I’m talking about the Teams (SEALS). I’m sure my friend Larry (uphill) will help me out in this area. The basics are; it allows you to breathe without having exhausting bubbles come to the surface. This is very important when trying to move undetected to an objective. The systems are a “Closed Circuit System” which has an onboard “Scrubber” which scrubs the excess CO2 buildup by using certain types of scrubbing mediums such as Soda Sorb. This type of system is great when trying to remain undetected in a hostile environment.
There are some problems when using a closed circuit system, they are very DANGEROUS! These are to be used by only HIGHLY SKIILED EXPERTS. You can and will Die if not using extreme caution when using these types of systems. Even being highly skilled Experts have died using these systems when having an equipment malfunction. I have known divers that have gotten an O2 hit and have died. The maximum depth for these types of systems is 33 feet or 1 Atmosphere. Unless using a Nitrox mix which allows you to go deeper.
Then we move into Commercial Deep Sea Diving which is on the other end of the spectrum. I’ll first start off saying that you cannot just wakeup one day and say I want to be a Deep Sea Diver and try to go to work off shore or for an inland Dive company. This is a very “Close & Closed” community. You have to go to one of the very few certified Commercial Diving Schools in the World. There are five here in the United States one in Scotland. I myself went to the College Of Oceaneering located in LA in Wilmington, CA. My Instructor came in from the Offshore and wanted to give back to the industry by teaching. He was a retired NAVY SEAL named John, I am leaving his last name off due to I don’t know if he would want his name out their on the net. Anyways, I’m getting off topic on my own thread here.
Once you go to school you become and a Dive Tender until you “Break-Out”, which means you become a diver. During this learning time, you tend other divers, perform rigging, getting tools ready to go down, change out soda sorb canisters, get meals, fix equipment, change out gas bottles, run Hyperbaric chambers, etc.
In commercial diving we wear what is referred to as a Hard Hat (Helmet) the ones that are used today are called a Superlite 17. They weigh around 27 lbs. The old day they used the old brass hat (Mark VI), these were very heavy, I think all of you have seen them used in movies before. They had canvas suits along with lead boots and a 150 pound lead weight belt. They have communication inside the helmet that allows the diver direct communications with “Topside”. The diver has an umbilical attached to the helmet and himself that goes all the way to the surface or “Dive Bell” (I’ll explain this in a minute) The diver also wears a “Bailout Bottle” which is inverted and worn on his back that has a hose that also goes to his helmet in case of an emergency. This should give him a couple of minutes of breathing gas.
The Divers umbilical attaches to a mixing board on the deck of the ship or barge. There is always a Diving Supervisor, a gas rack man (Diver) and Standby Diver on Deck along with two diver tenders and rigging crew at a minimum. If we are diving gas, we use a mixture of Helium and Oxygen. Helium is used to replace the gas Nitrogen. Helium is another inert gas that can be used to help deliver the Oxygen to the tissues of the body. There is a side effect of Helium, it makes you sound like Donald Duck but 10 times worse. We use Radio De-scramblers; this allows people on deck to better understand what the diver is saying.
The gas racks that are used are huge, they are the size of tractor trailers, the tubes are 40 feet long. We use many tubes during the course of a job. We do different types of jobs, some are shallow, then we use regular AIR, then we have midwater jobs like repairing a Riser, which we might be using Mixed gas in the 250 feet + level or we might be doing a repair job on the Ocean floor in the 500 – 750 foot range using SAT (Saturation)
Depending on the depths will require different mixtures of gases for the divers to work. In mix gas, we use like I stated a mix of Helium, a small % of Oxygen then maybe 10% Nitrogen. The Human body is just like a sponge. In Saturation Diving in essences means being “Saturated by Gases” if you take a sponge and run water over it, once it can’t take anymore, it becomes saturated, this holds true with the tissues in the human body when dealing with gases. A large person with a high fat content will take on heavy gases slower than someone with a lean body. Just the opposite is true when “Off Gassing”. A lean person will off gas quicker than a heavy person.
Saturation diving is used when large jobs that are going to take time to finish is when this type is used. Smaller jobs can get by using an open bell (a steel Platform that the diver stands inside and is lowered and retracted from the surface). In saturation the divers climb inside a pressurized container where they will live, work, eat and sleep in until the end of the job and decompression. In Sat everything is damp, your bedding, towels, sheets, pillows, etc. This is because your living under pressure, sometime extreme pressures depending on the depths. Lets look at how much pressure a diver lives under. Let’s say we are working on a pipeline at 785 feet. The living quarters are normally pressurized at 25 foot over bottom. So this means the divers are living at a depth in SAT around 760 feet. 760 x .445 PSI = 338.20 PSI that the diver is working, eating and sleeping around their body the whole time. I’m no going to get into explosive decompression, but just to say, it’s not very pretty.
In SAT, you have an army of people that do everything for you, they turn the water on, they flush the toliet, they prepair your food, they control your breathing gases 24 hrs a day 7 days a week. This is done until you break the seal and complete your decompression. It may take two weeks just to come back to the surface before you can exit the sat system. The area is so small inside, you take turns standing up and walking down the isles. Normally there are six man sat teams.
There is what is called a Diving Bell, this is a round large ball heavy reinforced for pressures that it will endure. (2) men get inside, then lock out from the main living chamber, then a hydraulic system moves the bell to the moon pool (A Large Hole in the deck of the ship) the bell is then lowered to the bottom where, one diver crawls out from the bottom hatch while the other diver remains inside the bell tending the divers umbilical, then they switch out.
I thought I would post some pics in my younger days.
These are pre digital.
SCUBA Diving at Seal Rock in CA. I'm on the far right.
Doing a Fiber Optic Cable Inspection across a river. I'm wearing a Superlite 17 here.
I'm doing a bridge Inspection on the Ohio River.
This is a Ship I lived on for 3 months working. It's called the Ocean Builder, it's 850' feet long. It has a 2,000 ton Rotary Crane.
A tug towing a barge with a new oil Platform we have to set.
This is a view of the Platform tied up next to the ship, you get the idea of the size were talking about.
Here we are getting ready to jump a diver to flood the legs to sink the platform.
A pic of the Saturation system on board, the bell is under water.
Here is a pic of the Diving Bell locked on to the system, you can see the water splashing up from the moon pool.
Inside the SAT System living quarters.
This is a 20,000 PSI Water Blaster we use to remove barnacles.
High Explosives getting ready to be set so we can remove an old platform
The Platform to be salvaged.
BOOM...go the charges...
Laying three pipelines at the same time in Mobile Bay, AL...They said it couldn't be done, and we did it.
See Ya, I'm out here!