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.

Delta P

00:11:28

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

Ringkasan

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.

Takeaways

⚠️ 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.

Garis waktu

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.

Peta Pikiran

Pertanyaan yang Sering Diajukan

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.

Lihat lebih banyak ringkasan video

Dapatkan akses instan ke ringkasan video YouTube gratis yang didukung oleh AI!

Teks

Gulir Otomatis:

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]