ST0155 Gas Engineering Operative: practice questions and mock tests
A 40-question closed-book test of the safety, science and technical decisions used in domestic gas engineering work.
Apprentices registered to ST0155 version 1.3 and preparing for the knowledge-test part of the Level 3 end-point assessment.
Standard
ST0155
Version
v1.3
Level
3
Exam at a glance
ST0155 · version 1.3
- Questions / papers
- 40 questions
- Time allowed
- 60 minutes
- Pass requirement
- 28/40
- Reference policy
- Closed book
What is the ST0155 Gas Engineering Operative test?
The ST0155 test checks whether an apprentice understands gas safety, combustion, appliances, pipework, controls, commissioning, fault-finding and the actions required when work is unsafe.
This page focuses on the knowledge-test method. The full end-point assessment may also include practical, observation or professional-discussion methods. Use the official assessment-plan links below to check the complete EPA.
When you take it
It is normally taken during end-point assessment, after the apprentice has completed training and passed through gateway. The employer, training provider and end-point assessment organisation agree the booking and sequence.
- 01
Training
Build the occupational knowledge, practical competence and workplace evidence.
- 02
Gateway
The employer confirms the apprentice is ready to enter end-point assessment.
- 03
Knowledge test
Sit the ST0155 multiple-choice knowledge test.
- 04
Other EPA methods
Complete the practical, observation or discussion methods specified by the assessment plan.
Try a practice question
ST0155 · Original practice material
With adequate oxygen, mixing and ignition conditions, hydrocarbon fuel mainly forms carbon dioxide, water vapour and heat.
Which option is being described?
Choose one answer, then check it.
ST0155 exam format and scoring
These are the recorded rules for this standard version. Always compare them with the final joining instructions from your end-point assessment organisation.
Delivery
Controlled and closed book.
Question style
40 four-option multiple-choice questions with one correct answer.
Books and materials
No reference books or notes are used.
| Paper | Coverage | Questions | Time | Grade boundary |
|---|---|---|---|---|
| Knowledge test | Knowledge mapped to the ST0155 test | 40 | 60 minutes | Pass 28/40Distinction 34/40 |
What to revise for ST0155
The current published Trade Exams library for this standard contains 400 original practice questions and 23 focused fact sheets. These are revision-library counts, not official exam weightings.
Knowledge-area map
Standard reference
ST0155
Gas safety system
- T01Gas safety and legal duties
- T02Combustion, flues and ventilation
- T03Pipework and pressure
- T04Appliances and controls
- T05Commissioning and testing
- T06Faults and unsafe situations
Gas safety and legal duties
01Competence, safe working, emergency actions and statutory responsibilities.
Combustion, flues and ventilation
02Air supply, products of combustion, flue performance and warning signs.
Pipework and pressure
03Materials, sizing principles, tightness, pressure and soundness decisions.
Appliances and controls
04Operating principles, safety devices, controls and manufacturer information.
Commissioning and testing
05Checks, measurements, records and safe handover.
Faults and unsafe situations
06Diagnosis, classification, isolation and escalation.
How to prepare for the ST0155 test
A practical four-stage revision sequence: understand the rules first, close topic gaps, practise decisions, then rehearse under the real time pressure.
- 1
Prioritise safe actions and escalation whenever a scenario presents an unsafe condition.
- 2
Link combustion symptoms to ventilation, flue and appliance checks.
- 3
Practise interpreting test results instead of memorising isolated values.
- 4
Complete 40-question mocks within 60 minutes and review the reasoning behind each answer.
Revision access
Questions, mocks and fact sheets
One exam, one clear price. Access ends automatically and never renews into a subscription.
£10
30 days of access
Everything for this exam for 30 days.
One-off payment. No automatic renewal.
£20
90 days of access
Everything for this exam for 90 days.
One-off payment. No automatic renewal.
ST0155 exam questions answered
Format, timing, version, preparation and booking questions—answered from the recorded standard and assessment-plan sources.
01What is the ST0155 Gas Engineering Operative exam?
The ST0155 test checks whether an apprentice understands gas safety, combustion, appliances, pipework, controls, commissioning, fault-finding and the actions required when work is unsafe. This page focuses on the knowledge-test method; the full end-point assessment may also contain practical or discussion-based methods.
02Who should use this ST0155 revision page?
Apprentices registered to ST0155 version 1.3 and preparing for the knowledge-test part of the Level 3 end-point assessment.
03When do apprentices take the ST0155 knowledge test?
It is normally taken during end-point assessment, after the apprentice has completed training and passed through gateway. The employer, training provider and end-point assessment organisation agree the booking and sequence.
04What is the ST0155 exam format?
Multiple-choice knowledge test. Controlled and closed book. 40 four-option multiple-choice questions with one correct answer.
05How many questions are there and how long does the test take?
40 questions and 60 minutes. Knowledge test: 40 questions, 60 minutes, pass 28/40.
06What is the ST0155 pass mark?
28/40. Knowledge test: pass 28/40; distinction 34/40.
07Is the ST0155 test open book?
Closed book. No reference books or notes are used.
08What subjects should I revise for ST0155?
The main areas are Gas safety and legal duties, Combustion, flues and ventilation, Pipework and pressure, Appliances and controls, Commissioning and testing and Faults and unsafe situations. The detailed coverage on this page stays within the knowledge mapped to this assessment method.
09How should I prepare for the ST0155 exam?
Prioritise safe actions and escalation whenever a scenario presents an unsafe condition. Link combustion symptoms to ventilation, flue and appliance checks. Practise interpreting test results instead of memorising isolated values. Complete 40-question mocks within 60 minutes and review the reasoning behind each answer.
10Which version of ST0155 does this page cover?
The page and practice pack are aligned to ST0155 version 1.3; they do not replace approved gas training or workplace procedures.
11Are the Trade Exams questions official live exam questions?
No. Trade Exams' 400 practice questions and 23 fact sheets are independently authored revision material. They do not reproduce recalled, live, confidential or password-protected EPAO questions.
12Where do the ST0155 exam details come from?
The format and scope are based on the listed Skills England standard and end-point assessment sources, checked for this content pack on 2026-07-29. Always confirm late changes and booking instructions with the employer, training provider or EPAO.
13How does Trade Exams access work?
Access is a one-off £10 payment for 30 days or £20 for 90 days. It never renews automatically.
Official sources and currency
Check the standard behind this page
The format and scope were checked on 29 July 2026. Assessment arrangements can change, so confirm the final booking details with your employer, training provider or EPAO.
Keep browsing