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 drier, perhaps brighter end to the day. Another humid day and becoming warm in any sunshine.
Rain, often heavy and sometimes thundery, eases away northwards, leaving a legacy of low cloud, hill fog and light rain.
Mr Thompson said it would pose a "challenge" before adding, "it's emergency funding and we'll use it really wisely".