Work is continuing to investigate and clean up BAE System’s Barrow shipyard after a major blaze ripped through the Devonshire Dock Hall.
The fire started in the early hours of Wednesday and emergency services remained at the scene for several hours.
Two people were taken to hospital with suspected smoke inhalation but were released.
BAE Systems said: “Following the fire in the Devonshire Dock Hall, a full investigation and clean-up activities are now underway.
“The affected area is accessible to essential personnel only but the remainder of the site is fully operational.
“We would again like to thank the emergency services and all our partners and agencies involved whose bravery and professionalism ensured our colleagues were quickly and safely evacuated from the area.
“We’re also grateful to the local community for their patience and co-operation throughout.
“The multi-agency response to the incident prevented significant damage to the facility and the submarine units within it.
“We are continuing a full assessment of the impact and are developing a comprehensive plan to progress remedial action but early investigations indicate the fire has had limited impact.
“Work continues on Astute Boat 6, which is currently in the water in the Devonshire Dock, and both the Dreadnought and SSN-AUKUS programmes are progressing.”
