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Free · original fictional extracts

Practice Canadian chart symbols without copying an official chart

Direct answer

This free 20-question Canadian chart-symbol quiz uses original, deliberately fictional diagrams to practise CHS Chart 1 terminology, metric soundings, chart datum, drying features, hazards, lights, cables, anchorages, currents, notes, and electronic-chart checks. Each response is explained. No official chart is reproduced, and every extract is non-navigational and unsuitable for passage planning.

Questions
20 original chart-reading exercises
Artwork
Compass-owned fictional extracts
Reference
Canadian Chart 1 terminology
Use
Teaching only, never navigation
Question 1 of 20Soundings
4.2COMPASS FICTIONAL TRAINING EXTRACT — NOT FOR NAVIGATION

On a Canadian metric chart, what does a plain 4.2 sounding normally represent?

Understand the result

Use this quiz as a revision plan

Review the explanation for every response, including answers you guessed correctly. The sections below show what the sample covers, what its score can and cannot mean, and where to continue.

What the quiz covers

  • Metric soundings and the stated sounding datum
  • Drying heights, charted depths, and tidal-height relationships
  • Rocks, wrecks, submarine cables, and anchorage symbols
  • Light descriptions and complete characteristic identity
  • Current arrows, rates, notes, cautions, and source status
  • Electronic-chart layers, scale, updates, and common-mode checks

Worked examples

Five representative questions with explanations

These examples are separate from the scored question sequence, so the live quiz can keep its own feedback timing.

Example 1

Does a sounding of 4.2 mean 4.2 metres of water will always be present?

No.

A sounding is referred to the chart's stated datum; actual water depth also depends on water level and other conditions.

Example 2

How is a drying height used in a depth calculation?

Subtract the drying height from the height of tide above chart datum.

The result is predicted water over the drying feature before safety margins and uncertainty are considered.

Example 3

Is the abbreviation beside a wreck enough to decide whether it is safe to cross?

No.

Depth, datum, scale, notes, survey/source information, tide, vessel draught, clearance, and uncertainty all affect the decision.

Example 4

What does Fl G 4s describe?

A green flashing light with a four-second period.

A complete light identity uses colour, rhythm, group if present, and period rather than colour alone.

Example 5

Why can two electronic chart displays still share one failure?

They may use the same position source, chart data, settings, power, or update state.

Two screens are not automatically two independent navigation references.

How to interpret the score

17–20
Strong recognition sample; investigate every context or datum miss.
13–16
Useful base; revisit the weak symbol and reference families.
0–12
Rebuild chart context, datum, and source checks before more plotting.

Continue by topic

Open Basic Coastal NavigationBuild chart symbols into datum, compass, fixes, tides, currents, and passage planning.Open resource Read a fictional nautical chartUse the Compass chart reader for layered symbol and distance practice.Open resource Practise Canadian buoyageConnect charted aids with the Canadian Region B system.Open resource

Frequently asked questions

Do these exercises reproduce Canadian Hydrographic Service charts?

No. The diagrams, positions, depths, labels, and geometry are original fictional teaching material. CHS Chart 1 is cited for terminology and conventions.

Can I use a fictional extract for navigation?

No. Every extract is deliberately non-navigational and lacks the official source status, coverage, corrections, warnings, and real-world context required for navigation.

Why must a symbol be read in context?

Its meaning can depend on scale, datum, nearby labels, notes, source quality, chart edition, and the surrounding feature—not just the mark drawn at one point.

Editorial record

Primary sources

Reviewed September 2, 2026. Compass uses these sources to check terminology, scope, and safety boundaries; the questions and diagrams remain independently authored.