Delta P

00:11:28
https://www.youtube.com/watch?v=AEtbFm_CjE0

الملخص

TLDRThe video focuses on the dangers of Delta P (differential pressure) in commercial diving, a major cause of fatalities. Delta P occurs where there is a significant pressure difference between two water bodies, creating a suction force that can trap divers. The video illustrates several tragedies caused by Delta P incidents and emphasizes the importance of understanding site layouts, valve systems, and potential hazards before diving. Safety recommendations include participating in pre-job meetings, using appropriate equipment, maintaining communication, and following lockout tagout procedures to avoid accidents. The key takeaway is to recognize and mitigate Delta P risks to prevent deadly incidents.

الوجبات الجاهزة

  • ⚠️ Delta P is a hidden danger in diving.
  • 🌊 It occurs with a pressure difference in water bodies.
  • 🚫 It can trap divers, making escape nearly impossible.
  • 🔍 Understanding site layouts and systems is crucial.
  • 🛑 Follow lockout tagout procedures rigorously.
  • 📞 Maintain constant communication during dives.
  • 🧠 Recognize potential Delta P hazards in advance.
  • 📏 Calculating water force can help prevent accidents.
  • 🚧 Use the right equipment to handle pressure risks.
  • ✋ Avoid cutting holes that can seal with your body.

الجدول الزمني

  • 00:00:00 - 00:05:00

    Delta P, or differential pressure, heavily contributes to diving fatalities by creating invisible forces that are difficult to escape once caught. The video explains Delta P by describing how pressure differences between two water bodies create strong force through openings, potentially trapping divers. Formulas show the pressures involved, highlighting the danger to divers who cannot perceive these forces underwater.

  • 00:05:00 - 00:11:28

    Real-life incidents illustrate the fatalities caused by Delta P, emphasizing the need for pre-job planning, understanding site layouts, and communication. The video stresses using safety practices like lockout/tagout and equipment precautions to minimize risks. It concludes that awareness and preparation are crucial, as Delta P strikes suddenly and lethally.

الخريطة الذهنية

Mind Map

الأسئلة الشائعة

  • What is Delta P in diving?

    Delta P stands for differential pressure and refers to the difference in pressure between two bodies of water.

  • Why is Delta P dangerous for divers?

    Delta P is dangerous because it can create a powerful suction that traps divers, making it nearly impossible for them to escape.

  • How does the video suggest avoiding Delta P hazards?

    The video suggests precautions such as understanding site layouts, following lockout tagout procedures, and avoiding equipment interference in potential Delta P situations.

  • What should divers do before taking a job to ensure safety?

    Divers should participate in pre-job meetings, understand the site layout, and ensure communication lines are established.

  • What is the formula for calculating the force of water through a hole?

    The formula is the area of the hole multiplied by the water depth difference multiplied by the PSI per foot of depth.

  • Can Delta P be detected by divers before it occurs?

    No, Delta P is invisible and strikes suddenly without warning, making advance detection challenging.

  • Why is a thorough understanding of piping and valve systems important for divers?

    Understanding these systems helps divers identify potential Delta P situations and take preventive measures.

  • What safety measures does the video recommend for new assignments?

    The video recommends considering Delta P hazards when choosing equipment and ensuring full communication capabilities.

  • What is the significance of 'lockout tagout' procedures?

    These procedures help prevent machinery and valve accidents by ensuring systems are securely shut off during maintenance.

  • What is the video's main safety message?

    The main message is to recognize and prepare for Delta P situations, as they can be fatal once they occur.

عرض المزيد من ملخصات الفيديو

احصل على وصول فوري إلى ملخصات فيديو YouTube المجانية المدعومة بالذكاء الاصطناعي!
الترجمات
en
التمرير التلقائي:
  • 00:00:01
    [Music]
  • 00:00:05
    this is a partial list of the commercial
  • 00:00:08
    diving fatalities over the past 15 years
  • 00:00:13
    all have one common cause Delta
  • 00:00:17
    P two out of three commercial diving
  • 00:00:20
    fatalities involve Delta P it is
  • 00:00:25
    invisible to a diver and it strikes
  • 00:00:27
    suddenly without warning There is almost
  • 00:00:31
    no way to escape once it grabs you
  • 00:00:34
    knowing what it is where it lurks and
  • 00:00:37
    how to avoid its grasp is the subject of
  • 00:00:40
    this
  • 00:00:43
    [Music]
  • 00:00:49
    video Delta P stands for differential
  • 00:00:53
    pressure our discussion refers to
  • 00:00:55
    situations where the pressures between
  • 00:00:57
    two bodies of water are dramatic
  • 00:01:00
    different in a situation like this the
  • 00:01:03
    bodies of water continuously seek to
  • 00:01:05
    equalize themselves in this example the
  • 00:01:09
    body of water on the right wants to rush
  • 00:01:11
    to the body of water on the left by
  • 00:01:14
    means of the pipe between them the
  • 00:01:16
    pressure exerted on the valve stopping
  • 00:01:18
    this water transfer can be enormous
  • 00:01:21
    depending on the difference in the
  • 00:01:22
    depths of the water and the diameter of
  • 00:01:24
    the pipe if the difference between the
  • 00:01:27
    depth of water is 50 ft and the diameter
  • 00:01:30
    of the pipe is 10 in the force of water
  • 00:01:33
    exerted on the valve is nearly 1,700
  • 00:01:37
    lb if the valve was suddenly opened and
  • 00:01:40
    your arm was near it would be sucked
  • 00:01:43
    into the hole
  • 00:01:44
    instantly trying to remove your arm
  • 00:01:47
    would be like trying to lift a car
  • 00:01:49
    completely off the ground with one hand
  • 00:01:53
    you could only remove your arm if the
  • 00:01:55
    pressures between the two bodies became
  • 00:01:57
    nearly equalized but at the pressure in
  • 00:02:00
    this example your body makes a perfect
  • 00:02:02
    seal stopping the bodies of water from
  • 00:02:05
    equalizing the formula for calculating
  • 00:02:08
    the force of water through a hole at a
  • 00:02:10
    particular depth
  • 00:02:12
    is the area of the
  • 00:02:15
    hole multiplied by the difference in
  • 00:02:17
    water depth multiplied by the PSI per
  • 00:02:21
    foot of water depth or in the situation
  • 00:02:24
    just described the 10-in hole equals 78
  • 00:02:28
    square in time 50 ft of water depth time
  • 00:02:34
    0.432 PSI per foot of freshwater depth
  • 00:02:37
    equals
  • 00:02:40
    1,685 lb of water pressure if you are
  • 00:02:43
    diving in saltwater be sure to use
  • 00:02:47
    0.445 PSI in your formula
  • 00:02:50
    instead you can't see or feel a Delta P
  • 00:02:55
    situation as you dive near it it grabs
  • 00:02:58
    you suddenly and it doesn't let go until
  • 00:03:00
    the pressure is equalized when it's got
  • 00:03:03
    you it's
  • 00:03:07
    gotcha as you watch the following
  • 00:03:10
    Recreations of actual Delta P incidents
  • 00:03:13
    ask yourself if you have on occasion
  • 00:03:16
    ventured into situations without being
  • 00:03:18
    thoroughly
  • 00:03:27
    prepared diver 1 enters theall Water
  • 00:03:30
    behind the dam structure in order to
  • 00:03:32
    clean the strainer of the Dam's drain
  • 00:03:35
    when the drain is cleared the tremendous
  • 00:03:37
    force of Rushing Water through the drain
  • 00:03:40
    grabs hold of diver 1 sucks him
  • 00:03:42
    partially inside and traps him diver 2
  • 00:03:46
    enters the water to help diver 1 and
  • 00:03:49
    becomes trapped
  • 00:03:50
    also diver 3 enters the water to rescue
  • 00:03:54
    divers 1 and two and after 40 minutes
  • 00:03:57
    returns to the surface with both divers
  • 00:04:00
    they are
  • 00:04:01
    dead diver 3 was hospitalized for
  • 00:04:05
    injuries suffered in the rescue
  • 00:04:07
    [Music]
  • 00:04:15
    attempts a scuba diver was repairing a
  • 00:04:18
    pool bottom at a depth of 10 ft he came
  • 00:04:22
    close to the open pool drain and was
  • 00:04:24
    drawn against it his body made a perfect
  • 00:04:27
    seal against the drain he was diving
  • 00:04:30
    alone and had no tender at the surface
  • 00:04:33
    no one knew he was trapped he ran out of
  • 00:04:36
    air and
  • 00:04:39
    [Music]
  • 00:04:45
    drowned two scuba divers entered a water
  • 00:04:48
    tower to unclog a drain using a fire
  • 00:04:52
    hose to blast away the silt and mud that
  • 00:04:54
    was clogging the drain the drain
  • 00:04:56
    suddenly opened a great suction
  • 00:04:59
    immediately occurred diver 1 was pulled
  • 00:05:03
    into the drain visibility was Zero diver
  • 00:05:06
    2 did not know that this had occurred
  • 00:05:10
    diver 2 surfaced Thinking diver 1 had
  • 00:05:13
    already come up diver 2 made repeated
  • 00:05:16
    but unsuccessful attempts to find him
  • 00:05:19
    diver one ran out of air and died
  • 00:05:22
    neither diver was Tethered to the
  • 00:05:24
    surface had communication with the
  • 00:05:26
    surface or with each other
  • 00:05:29
    [Music]
  • 00:05:35
    a surface Supply diver was working
  • 00:05:38
    offshore in 86 ft of water on a well
  • 00:05:41
    re-entry project he was using a drill
  • 00:05:44
    string to hook a trash cap inside a
  • 00:05:47
    13-in well casing the first attempt
  • 00:05:50
    failed to catch the cap the diver was
  • 00:05:53
    asked to stand by the hole to make sure
  • 00:05:55
    the string caught the cap he reported
  • 00:05:58
    when he saw the cap was hooked and began
  • 00:06:00
    to leave the drill string was pulled to
  • 00:06:04
    the surface rapidly because the cap was
  • 00:06:07
    nearly the size of the casing a great
  • 00:06:09
    suction developed as the cap came free
  • 00:06:12
    the Rushing Water grabbed the diver and
  • 00:06:15
    forced one leg into the hole up to the
  • 00:06:17
    pelvis the diver was
  • 00:06:21
    [Music]
  • 00:06:28
    killed diver one enters the water at a
  • 00:06:31
    hydroelectric generation plant his
  • 00:06:33
    assignment is to seal off leaks in a
  • 00:06:35
    large gate valve the three-person dive
  • 00:06:38
    team is assured by the plant's operating
  • 00:06:40
    Personnel that the gate valve is closed
  • 00:06:44
    diver one surfaces and reports that he
  • 00:06:46
    thinks the valves are
  • 00:06:48
    open the winch is started and closes the
  • 00:06:51
    valve a 30-in SLO gate is manually crank
  • 00:06:55
    shut the dive team questions the plant
  • 00:06:58
    personnel the valve indicator shows the
  • 00:07:01
    valve not fully closed plant Personnel
  • 00:07:04
    reply that the indicator is never
  • 00:07:06
    correct and typically the valve is
  • 00:07:08
    cranked until tight diver 1 re-enters
  • 00:07:12
    the water convinced that everything is
  • 00:07:14
    okay in a few moments he begins to
  • 00:07:18
    scream the dive supervisor tries to
  • 00:07:21
    contact diver one on the intercom the
  • 00:07:23
    tender and supervisor pulled the
  • 00:07:25
    lifeline and umbilical both have broken
  • 00:07:28
    from their attach match points the gates
  • 00:07:31
    are cycled open while waiting for the
  • 00:07:33
    rescue divers two attempts by the
  • 00:07:35
    company diver failed to locate diver 1
  • 00:07:39
    12 hours later diver 1's body is
  • 00:07:44
    [Music]
  • 00:07:51
    recovered when you accept a new job make
  • 00:07:54
    sure you take part in a pre-job meeting
  • 00:07:57
    again how are you right good be sure
  • 00:08:00
    that you understand the layout of the
  • 00:08:03
    site and how the piping and valve
  • 00:08:05
    systems work
  • 00:08:08
    together the diving supervisor should
  • 00:08:10
    have a simplified but site specific
  • 00:08:12
    schematic of the site and a diving
  • 00:08:15
    checklist to make sure nothing is on or
  • 00:08:17
    open that shouldn't
  • 00:08:20
    be your client also needs to know about
  • 00:08:23
    delap P if they take your concerns
  • 00:08:25
    lightly make sure they understand the
  • 00:08:28
    life-threatening hazard
  • 00:08:32
    always practice lockout tagout
  • 00:08:35
    procedures these are tried and true
  • 00:08:37
    methods that can eliminate machinery and
  • 00:08:40
    valve accidents if practice
  • 00:08:45
    religiously make sure to consider the
  • 00:08:47
    potential Delta P hazards of your new
  • 00:08:49
    assignment when choosing your
  • 00:08:53
    equipment make sure others in the water
  • 00:08:56
    and on the surface can tell exactly
  • 00:08:58
    where you are they should be able to
  • 00:09:00
    communicate with you at all times and be
  • 00:09:03
    able to get you out if you're
  • 00:09:10
    stuck make sure your equipment won't
  • 00:09:13
    interfere or become fouled if you must
  • 00:09:17
    be near a Delta P
  • 00:09:21
    situation there are certain techniques
  • 00:09:23
    that you can use to help reduce and even
  • 00:09:26
    eliminate delt P hazards the first step
  • 00:09:29
    is to recognize the potential forces
  • 00:09:32
    working on each other in your
  • 00:09:34
    environment learn the layout of the site
  • 00:09:37
    and how the system
  • 00:09:39
    functions calculate the force of water
  • 00:09:42
    at the depth you're working based on the
  • 00:09:44
    size of the openings at that
  • 00:09:47
    depth instead of cutting holes to drain
  • 00:09:50
    water or relieve pressure cut slots if
  • 00:09:54
    your body or equipment can't make a good
  • 00:09:56
    seal against the flow of water you can't
  • 00:09:58
    get
  • 00:10:00
    stuck fabricate a cover for the drain
  • 00:10:03
    that has a screen or make a cover that
  • 00:10:05
    has more than one hole a good distance
  • 00:10:08
    away from the other the idea is the
  • 00:10:11
    water can still get through even if your
  • 00:10:13
    body gets in the
  • 00:10:15
    way the goal of this video is to make
  • 00:10:18
    you aware of the potential for
  • 00:10:20
    differential pressure situations the key
  • 00:10:23
    is to recognize them beforehand and make
  • 00:10:26
    sure you are prepared to deal with them
  • 00:10:29
    because when it's gotcha it's
  • 00:10:34
    gotcha don't add your name to this list
  • 00:10:45
    [Music]
  • 00:10:52
    [Music]
الوسوم
  • Delta P
  • commercial diving
  • differential pressure
  • diving safety
  • pressure hazards
  • emergency procedures
  • safety measures
  • diver awareness
  • lockout tagout
  • incident prevention