Retailer John Lewis has been fined £20,000 for failing to do proper checks for asbestos while carrying out refurbishment work in Edinburgh.
Morris and Spottiswood, which was contracted to carry out the revamp, was also fined £20,000. They both admitted to three health and safety offences.
Neither of the firms carried out the necessary checks for asbestos before they allowed the work to begin in 2008.
Asbestos was disturbed during the work and 15 staff were potentially exposed.
Sheriff Elizabeth Jarvie, at Edinburgh Sheriff court, said she had reduced both fines from £30,000 to reflect the guilty pleas.
She said: "This was a serious and disturbing case but in any event no-one sustained any harm.
"As soon as discovery was made effective and immediate action was taken by the companies.
"On no view could it be said that either company was cavalier in their approach to the regulations indeed quite the reverse seems to have been the case in that systems were in place.
"Since the incident a thorough investigation was undertaken to ensure such incidents will not occur in the future.
"Both companies have incurred considerable expense in putting these systems in place."
Defence lawyer Robert Fife for John Lewis said the department store, which had pre-tax profits of £164m in the year leading up to January 2010, apologised for the incident.
Defence lawyer Craig Turnbull for Morris and Spottiswood said: "The offence is very much regretted by Morris and Spottiswood and they tender apologies and they have done what they can to prevent a recurrence."
In a statement in response to the fine imposed on John Lewis Edinburgh, managing director, Barry Matheson, said: "John Lewis takes today's decision of the court seriously.
"This incident has shaped stringent new health and safety protocols, which have now been implemented at John Lewis.
"Comprehensive new training, refresher courses, clearer communication and senior management involvement has been introduced as standard across all our branches in the UK."