Two enforcement notices have been served by health and safety inspectors on the owners of a mill hit by a fatal explosion.
Four people died after the blast at Wood Flour Mill in Bosley, near Macclesfield, last month.
The Health and Safety Executive said it had served the notices on Wood Treatment Ltd in relation to "dust issues" in sheds containing equipment on the site of the mill.
A prohibition notice has been served preventing work in one area, while an improvement notice has been served for a different area.
The HSE said the separate enforcement actions were due to differences in the level of risk in the two areas, adding that further enforcement action had not been ruled out.
Head of operations for the North West, Steve Smith, said: "HSE inspectors continue to work closely with emergency services in the ongoing investigation into the cause of this tragic incident.
"HSE specialists are on site to assist with the collection of evidence in order to try to establish exactly what happened."