Staffordshire Fire and Rescue Service went to an incident at Queen’s Hospital and Hobbycraft, Burton-on-Trent yesterday.
Two fire engines from Longton and one from Burton attended, after four Hobbycraft employees went to the hospital's A&E department after coming into contact with the substance.
The powder was later identified as Napthalene, which is a low risk product, and used to fumigate products shipped from abroad.
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A largely cloudy but mostly dry start.
A cloudy or misty start to the weekend, although mainly dry with sunny spells developing. Low cloud may linger in some spots.
A largely cloudy start to the weekend but mostly dry start. Through the day, some sunny spells are likely to develop.