• Welcome to ScubaBoard


  1. Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.

    Benefits of registering include

    • Ability to post and comment on topics and discussions.
    • A Free photo gallery to share your dive photos with the world.
    • You can make this box go away

    Joining is quick and easy. Login or Register now by clicking on the button

Diving and Seamanship

Discussion in 'Basic Scuba Discussions' started by Akimbo, Jun 12, 2014.

  1. Rich Keller

    Rich Keller Solo Diver

    # of Dives: 5,000 - ∞
    Location: Long Island NY
    3,354
    1,233
    113
  2. Storker

    Storker Divemaster

    # of Dives: 100 - 199
    Location: close to a Hell which occasionally freezes over
    12,579
    8,973
    113
    *shudder*

    Another not uncommon error is someone looping the rope around your hand when they need a strong grip on it. That's a great way to either lose a hand or follow the rope down under water. I think that my most, um, "urgent" message to my son at sea was when I saw him looping the anchor rope around his hand when he was hauling anchor while we were trying to reposition a 22-footer with a slipping anchor very close to a reef.

    Me, too. Also, I don't like rope coils on the dock. I prefer the coiled rope to be stowed aboard.


    --
    Sent from my Android phone
    Typos are a feature, not a bug
     
    Wingy likes this.
  3. Akimbo

    Akimbo Lift to Freedom Volunteer Staff Member ScubaBoard Supporter

    8,897
    7,215
    113
    This thread might be interesting to help you formulate plans if you have to abandon the vessel due to fire or sinking. I am a firm believer you should always be prepared to discover a new wreck, including the boat you came out on. :wink:

    http://www.scubaboard.com/forums/hawaii/487878-readers-poll-boat-sinking-don-scuba-life-vest.html

    It can happen anytime including while you are asleep below deck, on the bottom, or on deck. The more you think through the possibilities the more likely you are to survive yourself and help others.
     
    Last edited: Jul 22, 2014
    Wingy likes this.
  4. CaptainHornblower

    CaptainHornblower Captain

    # of Dives: I just don't log dives
    Location: Reno, NV
    64
    13
    8
    Ok, back to nautical factoids, terms, etc. Did you know where the expression "letting the cat out of the bag" came from? It's a reference to getting out the cat of nine tails used by the British navy for punishment. They kept it in a red velvet bag so the blood stains from prior use wouldn't show. It was a small whip with 9 strands on it, each strand roughly 1 yard long. Guess where the expression "going the whole 9 yards came from?" :)
     
  5. Akimbo

    Akimbo Lift to Freedom Volunteer Staff Member ScubaBoard Supporter

    8,897
    7,215
    113
    There are a few things you should know about marine electrical systems. At the simplest level, they are very different even when they look like devices in your house. Ask before plugging something in.

    The next-level of understanding marine electrical systems centers around verifying that voltages AND frequencies (50 or 60 Hz or cycles/second) are compatible with your device. This is especially important on a Liveaboard that caters to passengers from around the world. You not only risk burning up your device, but you could start a fire offshore where there's no fire department to call.

    There is another harder to understand aspect that is especially complicated by devices made for the North American Market: Grounding and Bonding. Every building with its own electrical service has one or more ground rods driven into the earth. This helps prevent people from being electrocuted. There's no place to drive a ground rod on a ship or boat. Using the vessels' hull to carry current to ground via sea water creates huge problems with electrolysis and can burn out other electrical devices onboard.

    Understanding this is really important for small boat owners that are large enough for a generator. Installing the wrong device can cause huge problems on your hull and everyone else's in the marina. Anodes can corrode 10x faster, bronze hull fittings can crumble, and you won't be very popular with the owner of that Aluminum boat tied up next to you.

    Above all, don't use a landlubber electrician!​

    Marine electrical systems are quite different, especially in North America. There is no Neutral that is tied to ground at the panel and expen$ive generators can get damaged when incorrectly interfaced to shore power. Don't use less expensive automotive battery chargers or many other grounded devices made for use onshore. Check first and get a marine electrician when you aren't positive. You can't trust the advice from your local hardware store.
     
    Last edited: Aug 12, 2014
    BurhanMuntasser likes this.
  6. Donnah

    Donnah Photographer

    # of Dives: 1,000 - 2,499
    Location: Key Largo, FL
    233
    112
    43
    As divers, not boaters, my husband/buddy and I took a boating safety class when we first came to the Keys. I think we were the only adults in the class who had NOT been caught with an on-water DUI.
     
  7. akex9898

    akex9898 Garibaldi

    2
    0
    0
    Hi I just made this account today because my interest was sparked while watching some youtube videos of scuba diving and it became aware to me that i could do this as a career? I am only a sophomore in high school and while i have always had an interest in marine biology, it never really occurred to me that i could make a living scuba diving. Can anybody give me some insight as to what it's actually like? Also, how much schooling would i need? Thanks.
     
  8. Wookie

    Wookie Secret Field Agent ScubaBoard Business Sponsor

    23,047
    31,589
    113
    This is almost 100% true, and the differences are miniscule. There is a neutral in marine systems, and sometimes a grounding shoe. 3 phase balanced systems have no ground, and modern electronics (UPSs, etc) require a ground, or you have to listen to the incessant beeping. In that case, a isolation transformer is installed with hot, common, and ground, and the ground is tied into the neutral on the primary side. The point is, a marine electrician certified by ABYC knows this. The guy hanging out at the marina might or might not.

    ---------- Post added August 17th, 2014 at 06:46 AM ----------

    IALA -International Association of Lighthouse Authorities yes, it has to do with driving on the wrong side of the road, except it's the wrong side of the channel. Doesn't necessarily apply to folks who drive on the wrong side of the road, examples Bahamas and France. Every chart will explain which IALA is in effect.

    Port and Starboard are the sides of the vessel. Right and left are directions. The confusing part is rudder commands. You might order 5 degrees of right rudder, or full right rudder, and when ordering full right rudder, the correct answer is "he rudder is hard to Starboard, sir".

    I never "cleat off" a line, either on the boat or on the dock. If you have to get away in a hurry, you have a half-hitch to deal with. Dock gets the eye, or, if tying up self tended, the eye comes back to the boat.
     
    Akimbo likes this.
  9. Akimbo

    Akimbo Lift to Freedom Volunteer Staff Member ScubaBoard Supporter

    8,897
    7,215
    113
    This is probably the most confusing aspect for North American land-based electricians to grasp. The white wire is often call "Neutral", but it is really a hot wire on a boat or ship because it comes off generator windings or a transformer. A true "Neutral" has virtually no voltage between it and a grounded wire. A shore or marine 120VAC generator will deliver 120VAC with no ground at all. Shore-based wiring won't deliver 120VAC without a Neutral grounded somewhere, usually at the power company's meter.

    The ABYC (American Boat and Yacht Council) specifies "bonding" the white 120VAC hot wire at the generator(s) to ground to make a lot of electronic items work properly, but it isn't quite the same animal.

    Here is a good article on why it is so critical to properly interface grounds and neutrals on a boat and shore power:

    http://www.abycinc.org/news/Boating_ESD_May_2013.pdf

    To the best of my knowledge, USCG requirements are consistent with ABYC for small boats and the ABS (American Bureau of Shipping) for larger vessels.
     
    descent likes this.
  10. Akimbo

    Akimbo Lift to Freedom Volunteer Staff Member ScubaBoard Supporter

    8,897
    7,215
    113
    It is hard to use your seamanship skills when you are losing your lunch over the side. Almost everyone gets sea sick under the right conditions. Some people are lucky and it passes along with their stomach contents while others are miserable until stepping back onshore. Scubaboard has tons of threads on sea sickness and I encourage you to explore them. Most people can learn to manage sea sickness with a little preparation.

    Doc Vikingo's Sea Sickness Remedies

    This sometimes embarrassing malady goes far beyond misery. It can be physiologically dangerous over an extended period, incapacitating in an emergency, and deadly to divers.

    Barfing in the Water
    There is a controversy over leaving your regulator in your mouth or removing it when vomiting underwater. Neither option is especially good. Leaving the mouthpiece in reduces your risk of aspirating sea water, but increases your chances of aspirating stomach acids and undigested solids that can obstruct your airway.

    FFM (Full Face Mask) users especially need to prepare for the possibility and practice how to manage it. Aside from getting sea sick, nausea is a symptom of Oxygen Toxicity and many FFM users use high PPO2 to accelerate decompression.

    The method I have decided on, but have yet needed to implement, involves facing down and holding the second stage with a finger poised on the purge button. The “plan” is to quickly remove the mouthpiece at the right moment to avoid debris and concentrate on not inhaling until the regulator is back in my mouth with the purge button is depressed. This is the time to forget about not touching anything. Plant yourself firmly on the bottom if you can so you don’t inadvertently ascend with your airway closed causing an embolism. Anyone who has been sea sick knows your ability to multitask disappears with your last meal. Being mid water would not be wise especially if your chosen method does not go well.

    It is worth considering your diet for 12-18 hours before your boat trip until you determine your susceptibility. A liquid protein breakfast drink is less likely to produce chunks that can clog your regulator and airway. Overheating in a suit with a tight neck seal and breathing Diesel exhaust are especially unhelpful. For most people, the ride out is the worst and symptoms often subside at anchor.

    It may be worth taking a few boat trips on whale watching or sports fishing boats before committing yourself to dive boat if you are concerned. There are a number of medications available, however loading up on them as a prophylactic measure will never teach you if they are necessary in the first place.

    Transderm Scop (The Patch) ? DAN | Divers Alert Network ? Medical Dive Article

    As for seamanship, always use the side of the boat that is downwind. :wink:
     

Share This Page