The charging bay with the taped plug and the blocked eyewash
The battery-charging bay for your 48 V lead-acid counterbalance trucks is in a corner of the warehouse. A roof extractor fan runs only when the general lighting is on, and the bay has no local exhaust. The eyewash is 25 m away, behind a stack of empty pallets. You are assigned to charge a truck at the end of the shift. You notice the charger plug casing is cracked and taped, the floor has old acid stains, and a colleague is about to top up cells with a plastic jug while wearing cotton gloves and safety glasses. The battery tops are wet with electrolyte, and the charger is still connected.
1. Identify the hazards and the corrections you would make before charging begins.
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Hazards:
- Hydrogen: lead-acid cells produce hydrogen during charging, especially near the end of the charge. Without local exhaust, gas can accumulate at roof level; any spark or flame is an ignition source.
- Electrolyte: wet cell tops and old stains mean acid is present; it can burn skin and eyes and damage clothing.
- Electrical: a cracked, taped plug can expose live conductors, overheat or arc.
- Emergency response: an eyewash 25 m away and blocked by pallets is not accessible when someone has acid in their eyes.
- Procedure and PPE: a plastic jug and cotton gloves are not suitable for acid; safety glasses leave the sides of the eyes exposed.
Corrections before charging: stop the colleague from topping up while connected; clear the eyewash access immediately; ventilate the bay and confirm the extractor is running; inspect the charger lead and plug and take the damaged charger out of service; provide a proper watering container, face shield or goggles, acid-resistant gloves and an apron; neutralise and clean the old stains; and confirm the emergency shower and eyewash are working.
2. Explain the correct sequence and PPE for checking and topping up electrolyte, including when to add water.
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PPE: chemical splash goggles or a face shield, acid-resistant gloves, an apron or acid-resistant clothing, and safety footwear. Remove rings, watches and other metal items; acid plus a metal watch on the wrist is a burn and shock risk. Do not eat, drink or touch your face while working on the battery.
Sequence: switch off and disconnect the charger before opening any cells, and follow the site's lockout procedure if the task requires it. Check the electrolyte level against the battery manufacturer's markings. Add water after the charge is complete, when the electrolyte is at its working level; overfilling before charging can cause acid to overflow as the electrolyte expands. The exception is when the plates are exposed: add just enough water to cover the plates before charging, then complete the top-up afterwards. Use distilled or deionised water, a proper battery watering container, and do not fill above the maximum line. Clean any acid on the battery top with the approved neutraliser, not a hose.
3. What would you do about the damaged plug and the blocked eyewash, and why do these matter beyond this shift?
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The damaged plug is an electrical defect, not a maintenance inconvenience. I would stop using that charger, isolate it, attach a 'DO NOT USE - OUT OF SERVICE' tag, and report it to the supervisor and maintenance. Taping a cracked plug is not a repair; it can hide a broken pin or exposed conductor, and the next person may plug it in without knowing. Only a qualified person should repair or replace the lead and plug.
The eyewash is a life-safety device. Acid in the eye needs immediate flushing; a 25 m route through a warehouse, past stacked pallets, is too long, and if the station is blocked the delay can turn a splash into permanent eye damage. I would move the pallets at once, keep the access route marked and clear, test the unit, and raise a work order for a permanent location or additional station closer to the bay. I would also report both issues through the site's hazard-reporting system, because they affect every operator on every shift, not just me tonight.