A 46-year-old man has died following a fall at Premier Foods in Claylands Avenue in Worksop.
Contractor Nigel Chester, who was from Arnold, was visiting the site to carry out a routine test of the fire alarm system on Wednesday when he fell in the Research and Development building at around 12pm.
He was taken to Bassetlaw Hospital where he was pronounced dead.
A post-mortem examination found Mr Chester died of head injuries as a result of a fall from height.
The circumstances surrounding the death are being jointly investigated by police and the Health and Safety Executive.
If you have any information call the Notts Police incident room on 0115 844 6906 or call Crimestoppers anonymously on 0800 555 111.