Launch offer — valid today only

📄 Digital book in PDF · read it on your phone or print it

ACS Core Gas Safety in Drawings: Tightness Test, Ventilation, Flues and ID vs AR, One Page Each Every Procedure Drawn, in Order

For the ACS domestic natural gas core (CCN1), reassessment or initial: tightness testing and purging, working pressure, ventilation, flue types, spillage tests, the flue gas analyser, CO and ID vs AR. Every topic has its own page: the drawing first, then what you need to remember. 69 illustrated pages.

START REVISING THIS WAY

🔒 Secure checkout · PDF by email · 30-day guarantee

Every topic, its own pageEach procedure drawn, with the explanation alongside
69 illustrated pages9 parts, from GSIUR 1998 to the assessment day
Up-to-date sourcesGSIUR 1998, IGEM/UP/1B, BS 5440 and the Unsafe Situations Procedure
PDF by emailFormat

Look Inside the Book

Every page has a large drawing and a box with the figures and steps you need to know:

Reg 3, Reg 26(9) and Reg 36: the four post-work checks and the 12-month landlord record
Reg 3, Reg 26(9) and Reg 36: the four post-work checks and the 12-month landlord record
Natural gas: mainly methane, relative density about 0.6, burns at roughly 5–15% gas in air.
Natural gas: mainly methane, relative density about 0.6, burns at roughly 5–15% gas in air.
Service pipe, ECV, regulator, meter, test point, pipework: one labelled drawing, in order.
Service pipe, ECV, regulator, meter, test point, pipework: one labelled drawing, in order.
IGEM/UP/1B Ed. 4: natural gas, LPG, LPG/air and caravans, up to 0.035 m³
IGEM/UP/1B Ed. 4: natural gas, LPG, LPG/air and caravans, up to 0.035 m³
Open-flued, room-sealed and flueless: three air needs, one page
Open-flued, room-sealed and flueless: three air needs, one page
Type A flueless, Type B open-flued, Type C room-sealed: what each one asks you to check
Type A flueless, Type B open-flued, Type C room-sealed: what each one asks you to check
Calibration, probe and water trap, then switch on in fresh air for warm-up and zero: before every FGA job.
Calibration, probe and water trap, then switch on in fresh air for warm-up and zero: before every FGA job.
ID = danger now · AR = could become dangerous · NCS = safe but not to today's standards
ID = danger now · AR = could become dangerous · NCS = safe but not to today's standards

Swipe to see more →

These are real pages from the book. The table of contents is the full one: 9 parts and 65 topics.

The Problem Isn't You. It's How It Was Explained.

You're at the assessment centre, standing at the meter rig. The assessor asks you to name each component from the service pipe to the appliance, and say what each one does.

You've fitted hundreds of them. But the manual describes that route in paragraphs: the ECV here, the regulator there, the test point a few pages later. Read in pieces, it doesn't come back in order.

Service pipe, ECV, regulator, meter, test point, pipework: one labelled drawing, in order.

In the book, that route is one labelled drawing: service pipe, ECV, regulator, meter, test point, pipework, left to right, with a short note on what each part is there for.

The same goes for the tightness test, ventilation, flue types, the analyser start-up and ID vs AR: each one has its own page.

You see the run and you say it in order, without going back to the manual to check.

COMPARE FOR YOURSELF

The Same Topic, Two Ways to Study It

THIS
  • The manual: line after line
  • Gas properties explained in words only
  • You walk into the assessment with doubts
Natural gas, as distributed in Great Britain, consists predominantly of methane (CH4), together with smaller proportions of other hydrocarbons and inert constituents. Its relative density, being approximately 0.6 with respect to air, causes any escape to rise and accumulate at high level, a consideration of some significance when assessing ventilation and the probable location of leaks. The gas is flammable only within limits of approximately 5% to 15% gas in air; outside this range, ignition will not be sustained, and complete combustion requires an adequate and continuous supply of air.
FOR THIS
  • Natural gas properties in one drawing
  • The key figures in one box
  • An escape rises (0.6 relative density): you check at high level
Natural gas: mainly methane, relative density about 0.6, burns at roughly 5–15% gas in air.
CONTENTS

Take a Look at the 9 Parts and 65 Topics

The law and your ACS, natural gas and combustion, meters and pipework, tightness testing and purging, ventilation, flues and spillage, combustion analysis, unsafe situations and the assessment day: 69 pages, all illustrated.

IThe law and your ACS · pp. 5-10
  1. GSIUR 1998 on one page
  2. Gas Safe Register, ACS and your certification body
  3. Initial ACS vs 5-yearly reassessment
  4. Which document answers which question
  5. Gas escapes: the first five actions
  6. RIDDOR and reporting gas incidents
IINatural gas and combustion · pp. 11-17
  1. Natural gas properties you need
  2. The combustion triangle and air needed
  3. Complete vs incomplete combustion
  4. Carbon monoxide: how it harms
  5. Flame pictures: lifting, lighting back, yellow tipping
  6. CO alarms: where and when
  7. Gross and net heat input
IIIMeters, pressures and pipework · pp. 18-25
  1. From the service pipe to the appliance
  2. The ECV: position, label and handle
  3. Standing vs working pressure
  4. The 1 mbar rule
  5. Gas rate by clocking the meter
  6. Pipe sizing from the tables
  7. Pipework rules: sleeves, clips and clearances
  8. Main bonding and the temporary continuity bond
IVTightness testing and purging · pp. 26-34
  1. When a tightness test is required
  2. Gauge, test point and readability
  3. Step 1–2: preparation and let-by test
  4. Step 3–4: raise to 20 mbar and stabilise
  5. Step 5: the 2-minute test
  6. Reading the permissible-drop table
  7. Failed test: trace, repair, retest
  8. Purge volume calculated
  9. Purging safely, in order
VVentilation · pp. 35-42
  1. Why ventilation exists: air for combustion
  2. Open-flued in a room: the 5 cm² per kW rule
  3. Free area vs grille size
  4. Several appliances in one room
  5. Compartments: room-sealed appliance
  6. Compartments: open-flued appliance
  7. Flueless appliances: cookers and water heaters
  8. Extract fans and open-flued appliances
VIFlues and spillage · pp. 43-51
  1. Flue types at a glance
  2. How a natural draught flue works
  3. Visual inspection of a flue
  4. Flue flow test with a smoke pellet
  5. Spillage test on an open-flued boiler
  6. Spillage test on a gas fire
  7. Room-sealed terminal positions
  8. Room-sealed checks: seals and case
  9. Chimneys, liners and the open-flue terminal
VIICombustion analysis and appliance checks · pp. 52-57
  1. The flue gas analyser: before you start
  2. Reading O2, CO, CO2 and the ratio
  3. The FGA check in order (BS 7967)
  4. Room CO checks
  5. Burner pressure and heat input checks
  6. Safety devices you must test
VIIIUnsafe situations: ID, AR, NCS · pp. 58-64
  1. The three categories in one picture
  2. Immediately Dangerous: the action sequence
  3. At Risk: the action sequence
  4. Not to Current Standards: what you do
  5. ID or AR? Ten job scenarios
  6. Warning labels and the warning notice
  7. Refusals, landlords and RIDDOR
IXBefore the assessment centre · pp. 65-69
  1. The tightness test and purge on one card
  2. Ventilation figures on one card
  3. Flues, spillage and FGA on one card
  4. Frequent mistakes in the practical
  5. The day before and the day itself

One Page, One Topic, All Clear

Think of it this way:

You're on a job. New boiler in, pipework finished, and before anything else you need a tightness test you'd put your name to.

You open the book at the tightness test and see the gauge on the test point, the let-by check, the rise to 20 mbar and the two-minute test, drawn in the order you carry them out.

Open-flued, room-sealed and flueless: three air needs, one page

The same with ventilation, flue types, the spillage test, the analyser start-up and ID vs AR: each one on its own page.

ACS Core Gas Safety Illustrated is 9 parts and 65 topics, all drawn, and it ends with one-page revision cards for the tightness test, ventilation, flues and FGA.

What you see drawn, you don't have to memorize.

What's Inside ACS Core Gas Safety Illustrated:

Ipp. 5-10

The law and your ACS

GSIUR 1998 on one page, Gas Safe Register and your certification body, initial ACS vs reassessment, which document answers which question, gas escapes and RIDDOR.

IIpp. 11-17

Natural gas and combustion

Natural gas properties, the combustion triangle, complete and incomplete combustion, how carbon monoxide harms, flame pictures, CO alarms and gross vs net heat input.

IIIpp. 18-25

Meters, pressures and pipework

From the service pipe to the appliance, the ECV, standing and working pressure, the 1 mbar rule, gas rating, pipe sizing, pipework rules and bonding.

IVpp. 26-34

Tightness testing and purging

When a tightness test is required, the gauge and test point, let-by, the rise to 20 mbar, the 2-minute test, the permissible-drop table, failed tests and purging.

Vpp. 35-42

Ventilation

Why ventilation exists, the open-flued rule per kW, free area vs grille size, several appliances, compartments, flueless appliances and extract fans.

VIpp. 43-51

Flues and spillage

Flue types, natural draught, visual inspection, the smoke pellet flow test, spillage tests on boilers and gas fires, room-sealed terminals and checks, chimneys and liners.

VIIpp. 52-57

Combustion analysis and appliance checks

The flue gas analyser before you start, reading O2, CO, CO2 and the ratio, the FGA check in order, room CO checks, burner pressure and safety devices.

VIIIpp. 58-64

Unsafe situations: ID, AR, NCS

ID, AR and NCS in one picture, the action sequence for each, ten job scenarios, warning labels and notices, refusals, landlords and RIDDOR.

IXpp. 65-69

Before the assessment centre

The tightness test and purge, ventilation, and flues, spillage and FGA on one card each, frequent mistakes in the practical, and the day itself.

At the end of the book: One-page revision cards for the tightness test, ventilation and flues, plus frequent mistakes in the practical.

SHOW ME WHAT'S INSIDE

Plus: 2 Free Books

ACS Core Practice Questions: Exam-Style, with Worked Answers

BONUS 1: «ACS Core Practice Questions: Exam-Style, with Worked Answers»

Value on its own: US$ 17.90

Test yourself on every core topic before the assessment centre, and see the full working behind each answer, not just the letter.

15 Common Gas Safety Mistakes: Before & After

BONUS 2: «15 Common Gas Safety Mistakes: Before & After»

Value on its own: US$ 14.90

The most frequent slips in testing, ventilation and flues drawn side by side with the correct way, so you spot them in seconds.

ACS Core Gas Safety Illustrated with 2 Free Books

  • ACS Core Gas Safety Illustrated: 69 illustrated pagesUS$ 63
  • BONUS 1: ACS Core Practice Questions: Exam-Style, with Worked AnswersUS$ 17.90
  • BONUS 2: 15 Common Gas Safety Mistakes: Before & AfterUS$ 14.90
  • High-resolution PDF to printIncluded
Total value US$ 95.80
YOUR PRICE:
US$ 27
You save US$ 68.80
YES, I WANT ACS CORE GAS SAFETY ILLUSTRATED FOR US$ 27

📄 This is a digital PDF book sent to your email: nothing is printed or shipped.

Secure purchaseEncrypted payment30-day guarantee

PDF by email: We email you ACS Core Gas Safety Illustrated as a PDF, together with the two free books. It's a single payment: no installments, no extra charges.

Who This Book Is For

You're on managed learning

You're on managed learning

Every core procedure on its own page, in the order you'll be assessed on it, to go with your portfolio and your mentor's jobs.

Your reassessment is weeks away

Your reassessment is weeks away

Five years of figures back in one place: tightness test, ventilation, flues, FGA and ID vs AR, to revise in the van or in the evening.

You're already on the tools

You're already on the tools

A printable reference for the checks you doubt on a job: which flue type, which test, ID or AR.

Everything You Get Today

US$ 95.80US$ 27
YES, I WANT ACS CORE GAS SAFETY ILLUSTRATED FOR US$ 27

📄 This is a digital PDF book sent to your email: nothing is printed or shipped.

30DAYS
GUARANTEE

30-Day Guarantee

Try ACS Core Gas Safety Illustrated for 30 days, bonus books included.

We refund everything if the file won't open, if the book isn't what you see here, if you were charged twice or if the email doesn't arrive. Just email us.

You pay once. No subscriptions.

Frequently Asked Questions

Is it for me if my 5-yearly ACS reassessment is coming up?

Yes. It follows the domestic natural gas core, CCN1, for the 5-yearly reassessment and for trainees heading to their initial ACS. It isn't a beginner's course: it puts the core procedures and figures back in order. It doesn't cover LPG or the appliance modules.

Where does the content come from?

From GSIUR 1998, IGEM/UP/1B, BS 6891, BS 5440-1 and -2, BS 7967 and the Gas Industry Unsafe Situations Procedure, checked against their current editions. Each page tells you which document it relies on.

Is it official material?

No. It's independent revision material, not published or endorsed by Gas Safe Register, IGEM, any certification body or assessment centre.

Does it replace my training or the assessment?

No. It doesn't replace training, managed learning, the ACS assessment or the standards themselves, and it doesn't qualify you to work on gas: by law, gas work must be done by a registered engineer.

Are the practice questions the ones in the assessment?

No. They're written for this book to test you on each core topic, with the full working behind every answer. They aren't official assessment questions.

When and how does it arrive?

The book and the 2 free books arrive as a PDF by email, to the address you enter at checkout.

I already have the training centre manuals. What does this add?

Your manuals explain each procedure in paragraphs. This book puts each one on its own page as a drawing, with the figures in one box and the steps in the order you carry them out. It's for the last weeks before the assessment, alongside your manuals, not instead of them.

Can I have it on paper?

Yes. The PDF prints on standard A4, so you can keep the pages you need in the van.

How does the refund work?

You have 30 days. We refund everything if the file won't open, if the book isn't what you see on this page, if you were charged twice or if the email doesn't arrive: just email us.

Before You Close This Page

No more rereading with nothing sticking.

The run from service pipe to appliance: you see it drawn, and that's it.

You walk into the assessment centre knowing where everything is.

Drawings make studying faster.

The book is right below.

One-time payment: US$ 27 · Guarantee: 30 days · PDF by email

YES, I WANT ACS CORE GAS SAFETY ILLUSTRATED FOR US$ 27

📄 This is a digital PDF book sent to your email: nothing is printed or shipped.