The Apprentice, the Nail Gun and the Missing Guard
You are a leading hand on a timber-frame townhouse site. A first-year apprentice, 17 years old, is using a framing nail gun to fix bottom plates. You notice the gun's contact (bump) trigger is set to 'bump fire' mode, the nose guard has been removed, and the apprentice is holding the workpiece with one hand while nailing with the other, working near the edge of a 2 m drop with no guardrail. He is wearing safety glasses but no hearing protection, and the compressor hose has a visible nick near the fitting. He says his supervisor showed him 'the fast way' and that he has done 'hundreds' of nails. The task is due by 4 pm and the concrete pour is booked for tomorrow.
1. List the hazards and the specific breaches you can see, and rank them by how urgently they need to be controlled.
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Hazards and breaches
| Hazard | What is wrong | Risk |
|---|---|---|
| Nail gun discharge | Nose guard removed and bump-fire mode active - the gun can fire on contact without a deliberate trigger pull | Puncture wounds to hands, feet, legs; nail to the eye |
| Single-handed operation | Holding the workpiece with one hand puts the hand in the line of fire and removes control of the gun | Nail through the hand or fingers |
| Fall from height | Working near a 2 m unprotected edge | Serious injury or fatality from a fall |
| Compressed air hose | Nicked hose near the fitting - may burst or whip | Struck by whipping hose, eye injury, loss of control of the tool |
| Noise | No hearing protection during sustained nailing | Progressive hearing damage |
| Supervision and competence | A 17-year-old first-year apprentice doing a high-risk task unsupervised, trained 'the fast way' | Underpins all the above |
Ranking by urgency
- Stop the nail gun use immediately - the combination of no guard, bump fire and one-handed work is an imminent risk of serious injury. This is the first action, before anything else.
- Move him away from the unprotected edge or install edge protection - a fall from 2 m is potentially fatal.
- Take the nicked hose out of service and tag it; do not use it until replaced or repaired.
- Fit hearing protection before work resumes.
- Fix supervision and training - the apprentice must not use the gun until he is trained, assessed as competent, and supervised by someone who models correct practice.
Why order matters The gun and the edge are both capable of killing or permanently injuring someone within seconds. The hose and noise cause harm over time and can wait until the immediate risks are removed. The supervision issue is the root cause and must be corrected before the task restarts, but it does not need to be resolved in the same minute as the gun.
2. What do you do in the next ten minutes, and how do you handle the supervisor who set this up?
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Next ten minutes
- Stop the task. Calmly take the gun from the apprentice, disconnect the air, and tell him to step back from the edge. Do not shame him - he was trained this way.
- Make the area safe. Barricade or cover the 2 m edge, or move the work to a guarded area. Tag the nicked hose out of service and remove it from the work area.
- Check for injury. Confirm nobody has been hurt; if there is a puncture wound, get first aid and record it.
- Secure the gun. Remove the bump-fire mode, refit the nose guard, and lock the tool away until it is compliant and its user is competent.
- Notify. Report to the site supervisor and the PCBU's safety contact, and record the incident and the corrective actions in the site diary. If a notifiable incident had occurred (serious injury), the PCBU must notify SafeWork NSW immediately.
- Arrange supervision. The apprentice does not resume nailing until he has been trained and assessed, and is supervised by a competent person.
Handling the supervisor
- Be factual, not accusatory: describe what you saw - guard removed, bump fire, one hand, no edge protection, nicked hose, no hearing protection - and the consequences that could follow.
- Point to the standard, not to personalities: the plant must be used as designed and with guards fitted, and young or inexperienced workers need supervision and training.
- Offer a practical path to the 4 pm deadline: refit the guard, switch to sequential fire, provide edge protection, get a second competent operator, and the work can proceed safely.
- If the supervisor insists on the unsafe method, escalate to the principal contractor's safety manager or the HSR, and if necessary contact SafeWork NSW. Document each step.
The point the exam is testing: a leading hand has both the authority and the duty to stop unsafe work, and the right response to schedule pressure is to fix the controls, not to accept the risk.