ECDIS Safety depth settings

Summary

This script from the Active Awareness Series discusses the critical role of chart depth settings in Electronic Chart Display and Information Systems (ECDIS) for safe navigation, especially in areas with shallow waters. It explains the importance of setting contours for shallow, safety, and deep waters, and how ECDIS displays these based on user input and available data. The dialogue between the captain and third mate covers the visual representation of different water depths using color coding in two and four color displays, emphasizing the significance of safety contours and the navigational dangers they indicate. The script also touches on the practical aspects of navigating near hazards and the use of ECDIS settings to ensure safe passage.

Takeaways

• 🌊 **Importance of Chart Depth Settings**: Chart depth settings are crucial for grounding prevention and safe navigation.
• 📊 **Understanding Contours**: Contours are lines on a chart that join equal depths, and they help in visualizing underwater terrain.
• 🛳️ **Master's Role in Setting Values**: The ship's master decides the chart depth settings based on ship management guidelines.
• 🔍 **ACTUS Display of Contours**: The Automatic Chart and Tabular Information System (ACTUS) displays contours based on input values or the next higher available contour.
• 🚫 **Shallow Contour Significance**: Shallow contours indicate high grounding risk areas that vessels should avoid.
• 🔳 **Safety Contour and Navigable Waters**: Safety contours separate navigable water depths from those that are unsafe, with specific color codes indicating different depths.
• ⚠️ **Safety Contour Alarms**: ACTUS systems can be set to alarm if a vessel is on course to cross the safety contour.
• 📍 **Isolated Danger Mark Symbols**: These symbols identify navigational dangers with safe passing depths less than or equal to the safety contour setting.
• 🌈 **Color Display Options**: ACTUS offers two color settings (two-color and four-color) to represent different depth areas for better navigation.
• 🌌 **Two Color Display for Simplicity**: The two-color display is preferred in shallow waters and during night navigation for its simplicity.
• 📚 **Knowledge Refreshment**: The discussion helps in refreshing knowledge about chart depth settings which is essential for safe navigation.

Q & A

What is the importance of chart depth settings in navigation?

Chart depth settings are crucial for organizing the display of safe depths and unsafe steps, which helps in grounding prevention and safe navigation.

What does 'ECTIS chart depth settings' refer to?

ECTIS chart depth settings refer to the user-input values for shallow contour, safety contour, safety depth, and deep contour in a navigation system.

How does the ship's master decide the values for chart depth settings?

The ship's master decides the values for chart depth settings based on the ship manager's guidelines.

What is the role of the ENC in displaying depth contours?

The ENC (Electronic Navigational Chart) is programmed to display depth contours equal to the input values or the next higher available contour if the exact input value is not available.

What is the significance of the safety contour in navigation?

The safety contour acts as a separation line between navigable water depths and depths less than the safety depth, helping to avoid areas of high grounding risk.

What does the color blue signify on the chart depth settings?

In the four-color display, blue color signifies areas of high grounding risk with depths less than the shallow contour, where the vessel should never enter.

How are depths that are equal to and lesser than the safety depth displayed?

Depths equal to and lesser than the safety depth are shown in black bold fonts, indicating that the vessel must not plan passage over these areas.

What is the purpose of the alarm set by the mariner if the vessel crosses the safety contour?

The alarm is intended to alert the mariner if the vessel is about to enter an area with depths less than the safety contour, promoting safety and avoidance of grounding.

What is the significance of the isolated danger mark symbols in relation to the safety contour?

The isolated danger mark symbols identify navigational dangers with safe passing depths less than or equal to the safety contour setting. Their display is governed by the safety contour setting.

What are the two types of color displays available in the ACTIS system?

The ACTIS system offers two color settings: two-color and four-color displays. The two-color display is simpler and preferred in shallow waters and during night navigation.

How does the two-color display differ from the four-color display in ACTIS?

In the two-color display, the light blue color from the four-color display is replaced by blue, and the gray color is replaced with white, simplifying the display for easier navigation in certain conditions.

Outlines

00:00

🚢 Chart Depth Settings for Safe Navigation

The first paragraph discusses the importance of chart depth settings for safe navigation, especially in areas with shallow waters. It explains the process of confirming the Electronic Chart Display and Information System (ECDIS) chart depth settings for an upcoming port call. The dialogue between the captain and the third mate covers the significance of these settings in displaying safe depths and unsafe steps. The explanation includes how the ship's master decides the values for the shallow contour, safety contour, safety depth, and deep contour as per the ship manager's guidelines. The paragraph also describes how ECDIS selects contours for display and the color coding used to differentiate between shallow and deep waters, with a focus on safety and shallow contours.

05:00

🌐 Understanding Safety Contours and Isolated Danger Marks

The second paragraph delves into the specifics of safety contours and isolated danger marks on a navigational chart. It explains how safety contours are set to ensure that a vessel does not cross into areas with depths less than the safety contour without proper caution. The paragraph also discusses the generic isolated danger mark symbols that identify navigational hazards with safe passing depths less than or equal to the safety contour setting. The captain shares insights on how the safety contour setting affects the display of these symbols and the importance of checking details of such hazards before navigating near them. Additionally, the paragraph covers the deep contour, which outlines the limit of deep water set by the user, and the color displays available in ECDIS, contrasting the two-color and four-color display options.

Keywords

💡Active Awareness

Active Awareness refers to the state of being vigilant and proactively attentive to one's surroundings and tasks. In the context of the video, it is crucial for the crew to maintain active awareness to ensure safety at sea, particularly when navigating through shallow waters and preparing for port calls. The video emphasizes the importance of this concept by discussing chart depth settings and their role in preventing grounding incidents.

💡Chart Depth Settings

Chart depth settings are the parameters inputted into a navigation system to display the contours of the sea floor on a chart. These settings are critical for safe navigation as they help mariners avoid shallow areas and plan their routes accordingly. In the script, the captain and third mate discuss the importance of confirming these settings to ensure they are appropriate for the coastal and port area they are navigating.

💡ENC

ENC stands for Electronic Navigational Chart, which is a digital nautical chart used for marine navigation. The script mentions ENC in relation to chart depth settings, indicating that the crew uses this digital tool to navigate safely by displaying the necessary depth contours on their navigation systems.

💡Contour

A contour on a nautical chart represents a line of equal depth or height. The video script explains how chart depth settings determine which contours are displayed, which is essential for identifying areas of varying depth and planning safe passage through waterways.

💡Safety Contour

The safety contour is a specific line on a chart that indicates the minimum depth considered safe for navigation. In the video, the safety contour is discussed as a critical setting that helps mariners avoid entering areas with depths less than what is considered safe, thus preventing grounding.

💡Shallow Contour

The shallow contour on a nautical chart outlines areas of high grounding risk, where the depth is less than the shallow contour setting. The video script emphasizes that vessels should never enter these areas, as indicated by the blue color in the four-color display setting.

💡Safety Depth

Safety depth refers to the minimum depth that a vessel can safely navigate. In the script, depths equal to or less than the safety depth are shown in black bold fonts, indicating that the vessel must not plan passage over these areas unless under specific conditions and after confirming UKC (Under Keel Clearance).

💡Deep Contour

The deep contour is a setting that outlines the limit of deep water as determined by the user. It is used to differentiate between navigable waters and waters that are considered too deep for safe navigation based on the vessel's draft. The script explains that waters deeper than the deep contour are shown in white color.

💡Color Display Settings

Color display settings on an ECDIS (Electronic Chart Display and Information System) allow mariners to visualize different water depths through color-coding. The video script describes both two-color and four-color display settings, with the latter providing more detailed visual cues to help with navigation in various conditions.

💡Isolated Danger Mark

Isolated danger marks are symbols used on nautical charts to identify navigational hazards. The video script explains that these marks are displayed based on the safety contour setting, with different visual representations depending on whether the hazard lies on the deeper or shallower side of the safety contour.

💡UKC

UKC stands for Under Keel Clearance, which is the minimum vertical distance between the deepest part of a vessel's hull and the sea floor. The script mentions that vessels may navigate in areas with depths less than the safety contour only after confirming adequate UKC, following ship manager's guidelines.

Highlights

Importance of chart depth settings for grounding prevention.

Arrival draft and coastal port area shallows discussed.

ECTIS chart depth settings reconfirmation requested.

Explanation of chart depth settings and their organization.

How ship's master decides chart depth settings values.

How ACTUS selects contour for display.

Example of safety contour input and display.

Explanation of shallow contour and its significance.

Description of safety depth and its display in black bold fonts.

Safety contour as the separation line between navigable and non-navigable waters.

Importance of safety contour in alarm settings.

Details on how to handle navigation near isolated danger marks.

Explanation of deep contour and its display.

Difference between two-color and four-color displays in ACTUS.

Pilots' preference for two-color display in shallow waters and night navigation.

How to enable two-color display in ACTUS.

Refresher on the knowledge of chart depth settings.

Transcripts

[Music]

active awareness series 3 chart depth

setting

very important for grounding prevention

[Music]

good morning third mate

good morning captain

how's it going

very well sir we have no traffic and the

weather is good

that's good i am looking forward to our

port call tomorrow morning

meetusa

very good our arrival draft is nine

meters and the coastal and port area may

have many shallows so i would like to

reconfirm the ectis chart depth settings

on the arrival enc

aisa

[Music]

here you go sir

thank you third it looks good our chart

depth settings are in order third do you

know the importance of the actus chart

depth settings

yes sir they are important these

settings organize the display of safe

depths and unsafe steps

yes that is correct there is no traffic

and the weather is good how about we

refresh our knowledge about chart depth

settings

[Music]

yes sir that would be great

[Music]

contours as you know are lines on a

chart that join equal depths

or equal heights

chart depth settings refers to the value

inputs by the user for the shallow

contour

safety contour

safety depth

and deep contour

yes sir but sir how are these values

decided

good question third the ship's master

decides the values of the charts depth

settings as per the ship managers

guidelines

but the first important thing to

understand is how the actus selects the

contour for display

most enc cells usually only contain

depth contours such as a 2 meter a 5

meter a 10

15

20

30

50 meter etc

the actus is programmed to display depth

contours equal to input values or the

next higher available contour

for example if the safety contour input

is 15 meters

a 15 meter contour will be displayed

if a 15 meter contour is not available

the next higher 20 meter or higher

contour will be displayed

another example as in our case we have

an input of 30 meters but enc does not

have a 13 meter contour so the actus

will display the next higher available

contour such as a 15 meter

i could understand it very well

i will explain the display with each

type of depth contour and safety depth

in a default setting of four color

display

the shallow contour outlines the shallow

waters of high grounding risk

depth less than the shallow contour is

shown in blue color the vessel should

never enter this area

corresponding to the safety depth

settings

depths that are equal to and lesser than

the safety depth will be shown in black

bold fonts and soundings deeper than the

safety depth in grey color

the vessel must not plan passage over

black bold soundings

however if needed a vessel may do so

only after confirming ukc in compliance

with the ship manager's guidelines

the safety contour is the separation

line between navigable water depths and

depths less than the safety contour the

safety contours value is equal to or

greater than the safety depth

waters between the safety contour and

the shallow contour are shown in light

blue color

as per regulations the actus should give

an alarm if within a specified time set

by the mariner his or her own ship would

cross the safety contour

usually a vessel does not plan a passage

or cross the safety contour towards the

depths that are less than the safety

contour

however when necessary a vessel may do

so only after confirming the ukc and

marking the no-go areas in compliance

with the ship managers guidelines

[Music]

third let me share another important

information about the safety contour and

the isolated danger mark

the generic isolated danger mark symbols

identify the navigational dangers that

have safe passing depths less than or

equal to the safety contour setting

it is important to note that the safety

contour setting governs the display of

the isolated danger mark symbols

by default all let dis display these

symbols only for the dangers that lie on

the deeper side of the safety contour

when these dangers lie on the shallower

side of the safety contour setting or

when these dangers have depths greater

than the safety contour setting they are

displayed with a black dotted line

around them

however do take note that on some actus

such as in the case of the furuno and

jrc actus the user can select a setting

to show isolated danger generic symbols

also on the shallower side of the safety

contour

therefore the user must make the correct

safety contour setting on the edges

in addition when planning courses or

navigating in the vicinity of such

dangers please check their details in

advance by clicking on the respective

symbol which will open the additional

information about the dangers

thank you sir this was indeed very

useful and important information

the deep contour outlines the limit of

deep water set by the user

waters between the deep contour and the

safety contour are shown in grey color

waters deeper than the deep contour are

shown in white color

[Music]

now let us look at the kinds of color

displays available in enactus the actus

has two kinds of color settings two

color and four color

by default the egg just shows a full

color display

[Music]

we have seen the four color display with

the earlier explanation now let us see

the two color display

yes sir

the two color display is simpler and it

shows navigable and depth areas less

than the safety contour in two colors

the two color display is preferred by

pilots and navigators especially in

shallow waters and during night

navigation

the two color display gets enabled by

selecting the two color depth settings

[Music]

in this display the light blue color

from the four color display is replaced

by the blue color thus the area between

the safety depth and the zero depth is

shown in a single blue color

the gray color from the four color

display is replaced with white color the

white color indicates safe waters with

depths greater than the safety contour

in some cases one may be able to

navigate beyond the safety contour but

must keep clear of the depths less than

the safety depth indicated in bold black

font

[Music]

sir now i understand the difference

between four color and two color

displays very clearly

i hope you found this discussion useful

yes indeed i could refresh my knowledge

of charge depth setting

thank you very much sir

[Music]

so

[Music]

you