Fire and Emergency New Zealand, ambulance personnel and a first response unit worked for about 30 minutes to free the fulltime employee of McCallums Group in Otepuni Ave.
The woman was taken to Southland Hospital to be treated for her injuries. Her condition last night was not known.
McCallums Group managing director Wayne McCallum said he was devastated by the accident.
Details about how the woman became trapped were unclear, but he was hoping to speak today with staff who saw the incident.
"We take health and safety protocols on site very seriously.
"At this stage our greatest concern is for all our staff’s welfare and especially for the injured woman."
About 40 staff were on site at the time of the accident.
Mr McCallum was extremely grateful to the staff member who had quickly activated the emergency shut-down mechanism.
"Today has been a pretty tough day on all concerned.
"Our family business cares about all our team’s wellbeing," he said.
By Toni McDonald