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Gas Measurement – a Safe Atmosphere

CBT 20 questions

First 5 of 20 questions — with answers

The correct answer is marked. Unlock the rest to study the whole test, online or offline.

  1. Question 1

    If the oxygen content of an enclosed space is less than 20 %, under what conditions should entry be made by personnel? Select the ONE correct answer.
    • In an emergency, only using suitable breathing equipment.
    • For a short period only using breathing equipment.
    • Only in pairs using breathing equipment.
    • Using breathing equipment.

  2. Question 2

    Stagnant water, some sewage systems and some oil cargoes can all be the source for a gas which is both flammable and toxic. What is this gas? Select the ONE correct answer.
    • Carbon dioxide.
    • Hydrogen chloride.
    • Hydrogen sulphide.
    • Nitrogen.

  3. Question 3

    The combustion control of an independent inert gas generator, supplying inert gas to a cargo tank system, is incorrectly set, giving incomplete combustion. What is the likely effect of this? Select the ONE correct answer.
    • Increased level of hydrogen sulphide gas in the inert gas.
    • Increased level of NOx and SOx in the inert gas.
    • Increased level of carbon monoxide in the inert gas.
    • Increased level of oxygen in the inert gas.

  4. Question 4

    The oxygen content in an enclosed space falls below 21 % during entry by personnel. What action should be taken? Select the ONE correct answer.
    • Complete the work as quickly as possible.
    • Increase the ventilation and continue working.
    • Stop the work and put on breathing apparatus before carrying on.
    • Stop working and leave the space immediately.

  5. Question 5

    What are the TWO main reasons for measuring the oxygen content of an enclosed space onboard a ship? Select the TWO correct answers.
    • To check if the oxygen content is low enough to avoid flammable mixtures.
    • To check the amount of hydrocarbon gas present.
    • To ensure the oxygen content is sufficient to allow safe entry.
    • To check the amount of toxic gases present.

Preview — 5 of 20 questions

You are seeing the first 5 questions with answers. Unlock the remaining 15 to study the whole test — online or offline.

About this CBT test

Gas Measurement – a Safe Atmosphere is a CBT test with 20 questions and verified answers. Common topics include: cargo tank, oxygen content, threshold limit, gas, space, exposure, term, effect.

You can practise the free questions online — one at a time, with the correct answer — or unlock the whole test and download it to study offline, without internet.

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