UK ACS / CCN1 revision — micro lessons + mock exams

Pass your gas assessments withstructured revision that actually sticks.

GasTheory turns CCN1 topics into short micro lessons and realistic exam-style questions — so you can revise in 10–20 minute bursts and see your weak areas fast.

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Fast to evaluate

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Built around CCN1

Regs, combustion, flues, ventilation, tightness testing, pipe sizing and more.

No fluff

Clear wording, balanced options, instant explanations, real exam feel.

Quick demo (2 minutes)

See the exact learning flow: micro lesson → exam question.

This is the same structure used across all topics — short revision, then questions that lock it in.

Micro-lesson example · FundamentalsLet-by & tightness testing

Carrying Out the Tightness Test

How to test the installation for pressure tightness after completing the let-by stage.

The meter inlet valve is opened gradually to raise the pressure to 20–21 mbar. The valve is then turned off at the test position.

The pressure is allowed to stabilise for one minute. If necessary, adjust back to 20–21 mbar after stabilisation.

After stabilisation, observe the gauge for a further two minutes to identify any pressure loss that would indicate a leak.

Key points to remember

• Test pressure must be between 20–21 mbar.
• Stabilisation is one minute, then two minutes monitoring.
• Pressure loss outside criteria indicates a leak.

Inside GasTheory, each topic includes multiple micro lessons like this, matched to real CCN1 areas.

Exam-style question

Tightness testing — quick check

Answer to reveal explanation

What pressure is used for a low-pressure tightness test?

What you get in the full app

• Full topic library (CCN1 fundamentals + appliances).
• Custom quiz lengths, instant explanations, progress tracking.
• Learn → practise → repeat, without guessing what to do next.

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How it works

A simple revision loop that keeps you moving.

Cold traffic needs clarity. This is the exact path GasTheory is designed for: understand → practise → see results.

1) Learn the rule

Micro lessons break CCN1 topics into small steps with key points you can recall fast.

2) Practise like the exam

Realistic multiple choice questions with instant explanations so you don’t build bad habits.

3) Improve the weak areas

Progress tracking shows what to revise next, so every session has a clear purpose.

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Built for real gas work

Learn in the same chunks you’re tested on.

Topics follow real UK gas training: regs, combustion, flues, ventilation, pipe sizing, meters, tightness testing and more.

Micro lessons that fit your day

Short, focused lessons mean you can revise in 10–20 minute bursts after work.

Questions that feel like the real thing

Balanced options, clear wording and quick explanations designed for exam confidence.

See your weak areas instantly

Topic-level progress shows where scores are low so you can focus properly.

“Having everything broken into small lessons and quick quizzes made it feel manageable.”

— Early GasTheory learner

Ready to revise properly? Start with the full library and track your progress.

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