Overlapping Hazards Ten Minutes Before Closing
The shop closes at 17:00 and it is 16:40 on a Friday. Five bays are in use. In bay 3 an apprentice is cutting a seized exhaust bracket with a 100 mm angle grinder while, three metres away, a co-worker washes parts in an open pan of gasoline. The vehicle in bay 3 is held up by a hydraulic trolley jack only; no stands are under it. In bay 1 the wall-mounted dry-chemical extinguisher gauge sits at zero. The main walkway is partly blocked by a stack of tyres, and the rear exit is chained because the shutter lock is broken. The shop supervisor left at 15:30 to buy parts and is not answering his phone. The apprentice wears safety glasses but no face shield, and his sleeves are rolled up. The owner has told staff that overtime is not allowed and that every job must be finished before closing. You are the senior technician on the floor.
1. Rank the hazards in this scene in the order you would control them, and state your very first action. Explain why fitting a face shield on the apprentice is not that first action.
Read the worked answer
Rank by severity and imminence, not by how easy the fix is:
- Gasoline vapour plus grinder sparks - ignition of fuel vapour can injure everyone in the shop, not just the apprentice. Highest priority.
- Vehicle on a trolley jack with no stands - crush injury is fatal and the jack can creep in seconds.
- Chained rear exit and a discharged extinguisher - these turn a small fire into a fatal one.
- Tyre stack in the walkway - egress and trip hazard.
- Missing face shield, rolled sleeves - real, but the consequence is limited to one person and one injury.
First action: stop the cutting - switch the grinder off at the plug, not just release the trigger - then remove the ignition source from the fuel: close the wash pan, move it outside or to the designated wash station at least 6 m from any hot work, and do not restart until the area is clear of vapour. Second, lower the vehicle onto stands before anyone goes under it. Third, unchain the exit and clear the tyres.
PPE is the last line of defence and protects one person from one hazard; it does nothing to the gasoline or the jack. Under the hierarchy of controls you eliminate or separate the hazard first, which is why the shield is step five, not step one.
2. The supervisor is unreachable and the owner's rule is 'no overtime, finish every job'. Describe what you say, to whom, and how you record it in the next 20 minutes.
Read the worked answer
A senior technician's stop-work authority for imminent danger overrides a production rule; the rule cannot make a fire or a crush safe. Sequence:
- Announce and secure. Tell the crew in bay 3 to stop, move the gasoline and the grinder apart, and keep people out of that bay. This takes two minutes, not overtime.
- Phone the owner (voice, not text) and state facts only: open gasoline 3 m from grinding, vehicle on a jack with no stands, gauge at zero on the extinguisher, exit chained. Then state what you have already done and what you need - authority to hold the bay, a replacement extinguisher tonight, and a repair order for the shutter.
- Log it. Enter the time, the people present, the controls applied and the owner's answer in the hazard/incident register. Note the supervisor's unavailability.
- Leave a written handover on the supervisor's desk and brief the crew at the bay, assigning one person to keep the wash area clear until the pan is stored properly.
If the owner instructs you to continue cutting beside the fuel, refuse that specific task and record the refusal - that is a legitimate right-to-refuse situation. Ten or fifteen minutes of lost time costs far less than a fire, an injury claim, or a labour inspection finding. Next morning, hold a toolbox talk and fix the causes: a labelled wash station away from hot work, an extinguisher on monthly inspection, and a working shutter lock.
3. Name two controls that would stop this same situation recurring next month, and classify each one in the hierarchy of controls.
Read the worked answer
Control 1 - relocate and enclose parts washing (engineering control). Build a dedicated wash station with a lidded, self-closing solvent pan, placed away from any hot-work bay, ideally with local exhaust. This removes the fuel from the spark rather than managing the two together. Engineering controls rank above procedure because they work even when someone forgets.
Control 2 - hot-work permit plus a written pre-task checklist (administrative control). Before any grinding, cutting or welding, the technician signs a short card: flammables removed or covered, extinguisher present and charged, screens in place, jack stands under the vehicle. The supervisor countersigns. Pair this with a monthly extinguisher inspection tag and a closing-time checklist covering egress and exits, because the two failures in this shop (dead extinguisher, chained exit) were maintenance and housekeeping lapses, not skill lapses.
Note what is not in the list: telling people to 'be careful', or buying face shields. Those are last-resort measures that leave the fuel, the jack and the blocked exit exactly where they are. Also worth adding as a substitution control: replace the gasoline wash with a water-based or low-flammability cleaner, which removes the hazard class entirely.