CSCS Tunnelling Specialist Test
TUNNOperatives working in tunnels, shafts and underground construction.
Sitting the TUNN test soon? Practise under exam conditions on our timed paper: 50 questions in 45 minutes, 20 on Tunnelling and 30 from the core.
50
questions
45
minutes
45/50
to pass (90%)
£23.50
test fee
What the Tunnelling test covers
The Tunnelling specialist section tests underground atmospheres and gas monitoring, emergency egress and refuge, ground support and face stability, fire precautions underground, and compressed-air working. Those questions sit alongside the five core Operatives knowledge areas, and CITB calls this specialism Tunnelling. In detail:
- Underground atmospheres and gas monitoring
- Emergency egress and refuge
- Ground support and face stability
- Fire precautions underground
- Compressed-air working awareness
Practise Tunnelling questions
A practice quiz of 20, drawn fresh each time from 101 exam-style questions with worked explanations, written for the TUNN specialist section from the regulations and HSE guidance that govern this work.
Tunnelling (TUNN): practice quiz
- 20 questions · 30 minutes · pass mark 90%
- Answers and explanations are shown at the end, with every question to review.
- A fresh 20 questions every time, drawn from all 101 in this bank.
- About 90 seconds a question, against about 54 in the real test, so there is time to think.
10 sample Tunnelling questions and answers
These 10 come from the 101 questions the practice quiz above draws from, written out with the correct answer and the reasoning behind it. Read them through when you want to revise rather than test yourself.
1. A job needs doing inside a shaft that counts as a confined space. Under the Confined Spaces Regulations 1997, what must be settled before anyone goes in?
Answer: Whether the job can reasonably be done without anyone entering the shaft
- A) Whether the shaft was entered safely last shift, so the air is fit
- B) Whether there is room in the shaft for two people to work side by side and watch one another
- C) Whether the job can reasonably be done without anyone entering the shaft (correct answer)
- D) Whether the shift can be finished before the end of the day, so the shaft is not left open
Why: The Confined Spaces Regulations 1997 say no one may enter a confined space to carry out work unless it is not reasonably practicable to achieve that purpose without entering. Avoiding entry comes before every other control.
2. You are about to go into compressed air in a tunnel. Which of these is banned outright by the Work in Compressed Air Regulations 1996?
Answer: Having any smoking materials with you
- A) Having any smoking materials with you (correct answer)
- B) Wearing a hard hat and high visibility clothing
- C) Drinking water after you have been decompressed
- D) Carrying a hand torch into the working chamber
Why: The Work in Compressed Air Regulations 1996 state that no person shall smoke or have with them any materials for the purpose of smoking when in compressed air. The same regulations also ban alcohol in compressed air, and require suitable drinks to be available during or after decompression.
3. A shaft is to be sunk through ground known to carry live buried services. Under CDM 2015, when may that work start?
Answer: Only once suitable and sufficient steps have been taken, so far as is reasonably practicable, to prevent the risk from the buried service the shaft will pass through
- A) As soon as the ground on the line of the shaft has been scanned with a cable avoidance tool and the marks have been sprayed on the surface, whether or not anything was found
- B) Only once suitable and sufficient steps have been taken, so far as is reasonably practicable, to prevent the risk from the buried service the shaft will pass through (correct answer)
- C) Only once the owner of the buried service has agreed in writing to pay for any damage the sinking of the shaft causes to their apparatus
- D) As soon as a banksman has been posted at the top of the shaft to watch the ground below him for any sign of a service being struck
Why: CDM 2015 regulation 25(4) says construction work liable to create a risk from an underground service, or from damage to or disturbance of it, must not be carried out unless suitable and sufficient steps have been taken to prevent the risk so far as is reasonably practicable. Scanning alone is not enough if nothing is done about what it shows.
4. Precast concrete segments have to be brought up to the tunnel face and built into the ring. Under the Manual Handling Operations Regulations 1992, what should the employer look at before anyone lifts anything?
Answer: Whether the segments can be lifted and placed by machine, so that nobody has to handle them by hand at all
- A) Whether the segments can be lifted and placed by machine, so that nobody has to handle them by hand at all (correct answer)
- B) Which member of the gang has the strongest back for lifting the segments at the face
- C) How many of the gang it takes to lift one segment between them and walk it up the tunnel to the ring being built
- D) Whether gloves and knee pads are enough protection for the lift down in the heading
Why: The Manual Handling Operations Regulations 1992 regulation 4(1)(a) requires the employer, so far as is reasonably practicable, to avoid the need for employees to do manual handling that carries a risk of injury. Assessing the lift and reducing the risk come next, under 4(1)(b), and only where avoiding it is not reasonably practicable.
5. Which statement about getting to and from the tunnel workings is correct under CDM 2015?
Answer: There must, so far as is reasonably practicable, be suitable and sufficient safe access to and egress from every place in the workings where construction work is being carried out
- A) Safe access is only needed at the portal and at the shaft top, because the face moves every shift and no fixed route can be kept up to it as the tunnel advances
- B) Safe access is only required where the workings are more than 2 metres below ground level, which takes in the shaft itself but not the tunnel driven off the bottom of the shaft
- C) Safe access is a matter for each gang to organise for itself once it is past the shaft bottom, since only the gang knows where it will be working in the tunnel that shift
- D) There must, so far as is reasonably practicable, be suitable and sufficient safe access to and egress from every place in the workings where construction work is being carried out (correct answer)
Why: CDM 2015 regulation 17(1) requires suitable and sufficient safe access to and egress from every place construction work is being carried out, so far as is reasonably practicable. Regulation 17(3) goes further and requires action to stop anyone using access that does not meet that standard. There is no depth threshold.
6. Which health effect of working in compressed air does HSE describe as a long-term, chronic condition that damages the long bones, hip or shoulder joints?
Answer: Dysbaric osteonecrosis
- A) Barotrauma of the ears
- B) Hand-arm vibration syndrome
- C) Noise-induced hearing loss
- D) Dysbaric osteonecrosis (correct answer)
Why: MS35 lists dysbaric osteonecrosis as a long-term, chronic condition which damages the long bones, hip or shoulder joints. Barotrauma is direct pressure damage to air spaces such as the ears.
7. What does HSE's guidance say about a compressed air worker's own health and exposure record?
Answer: The worker has a personal responsibility to keep it safe and present it to their employer so it can be updated and checked
- A) The worker has a personal responsibility to keep it safe and present it to their employer so it can be updated and checked (correct answer)
- B) The worker never sees it, because the appointed doctor keeps it locked away in the site medical centre for the whole contract
- C) The worker only needs it when they apply for a new CSCS card or renew their existing card
- D) The worker can throw it away once they stop working in compressed air on that contract
Why: MS35 paragraph 66 says employees have a personal responsibility to safeguard their health and exposure record and present it to their employer so it can be updated and checked before entering compressed air.
8. Why does HSE's guidance for appointed doctors say old injuries and arthritic changes in a compressed air worker should be carefully assessed?
Answer: Pain from them could be confused with decompression illness
- A) Healed fractures may break again as the air pressure rises
- B) Joint injuries make it harder for a worker to clear their ears
- C) Pain from them could be confused with decompression illness (correct answer)
- D) Old joint injuries heal faster under pressure, so they can be ignored
Why: MS35 paragraph 48 tells appointed doctors to assess old injuries and arthritic changes for their effects on safety and for their liability to cause pain which could be confused with decompression illness.
9. Overalls and materials in a tunnel are described as 'fire retardant'. What does HSE's training material say about them?
Answer: They are harder to ignite or burn more slowly, but they can still catch fire
- A) They are harder to ignite or burn more slowly, but they can still catch fire (correct answer)
- B) They cannot catch fire at all, so they can be stored right next to hot work
- C) They stop a fire spreading, so no extinguishers are needed nearby
- D) They give off no smoke when burning, so self-rescuers are not needed
Why: HSE's notes say fire retardant or fire resistant materials improve safety by being more difficult to ignite or burning more slowly, but they can still catch fire.
10. A crane is being set up to lower materials down a shaft. Under LOLER regulation 6, how must lifting equipment be positioned or installed?
Answer: To reduce, as low as reasonably practicable, the risk of the load striking someone, drifting, falling freely or being released
- A) Wherever the crane driver chooses on the day, provided they can see the load at the bottom of the shaft
- B) On the far side of the site from the shaft, so that the crane cannot fall into it if the ground gives way
- C) To reduce, as low as reasonably practicable, the risk of the load striking someone, drifting, falling freely or being released (correct answer)
- D) As close to the shaft edge as possible, so that the slinger standing at the top can reach the load without having to lean out
Why: LOLER regulation 6(1) requires lifting equipment to be positioned or installed to reduce to as low as reasonably practicable the risk of the equipment or load striking a person, or of the load drifting, falling freely or being released unintentionally.
How the Tunnelling test is structured
CITB builds every Specialist test the same way: the five core knowledge areas from the Operatives test, plus questions specific to your specialism. Those core areas are working environment, occupational health, safety, high risk activities and specialist, and they account for the larger share of the 50 questions. The practical consequence is that most of your revision for the TUNN test is the same revision every operative on site does, so start there and add the specialist material on top.
Same format as every HS&E test
50 questions in 45 minutes with a 45 out of 50 pass mark. Five wrong answers are allowed and a sixth fails you.
Booked as one exam
The core and specialist questions come in one 45-minute appointment costing £23.50, not as two separate sittings.
Your card decides it
The specialism follows from the CSCS card you are applying for. Confirm with the official Card Finder before booking.
Revising for Tunnelling: fix the core first
Because the core is shared, the fastest way to raise your score on any specialist test is to fix weaknesses in the core knowledge first. Sit a full CSCS mock test for Operatives cold, read the per-topic breakdown, then drill whichever of the CSCS test questions and answers cost you the most marks. Come back to the specialist material once the core is reliable, because a specialist section cannot rescue a weak core: the core is simply the bigger half of the paper.
When you are clearing 45 out of 50 consistently rather than once, read what ID to bring and how to book the CSCS test. Turning up without the right identification means no test and no refund, which is the commonest avoidable way to lose the £23.50.
Related specialist tests
These sit closest to Tunnelling in trade and in hazard. If you are unsure which specialism your card requires, compare them before you book.
Next steps
Confirm this is the right test with the official CSCS Card Finder, then book your Specialist test. Compare the other 11 specialist tests if you are unsure.
Sit a timed 50-question TUNN paper, 20 Tunnelling questions and 30 from the core, on the CSCS Specialist mock test.
Topic name and code verified against citb.co.uk, July 2026.