A focus on preventing major offshore incidents has led some companies to neglect general maintenance, it has been claimed.
The Health and Safety Executive (HSE) warned day-to-day worker safety must not be sidelined, as poor maintenance could lead to serious accidents.
Areas of concern included walkways and stairways.
The HSE commended companies for efforts to ensure "safety critical elements" were working effectively.
HSE's head of offshore, Steve Walker, said the report into external corrosion management highlighted areas of concern.
The HSE said the report followed inspections made between July 2007 and March this year which found the physical condition of installations varied from good to poor when looking at maintenance management systems for non-safety critical elements.
He said: "The management of external corrosion to safety related plant and equipment offshore must not become the 'poor relation' offshore.
"While we recognise the commitment of companies in preventing any failures that could lead to major incidents offshore, it is essential that they are not neglecting the general fabric of their installations.
"Offshore installations that progressively deteriorate and corrode, with hazardous walkways and poorly supported pipes or other infrastructure are not only putting workers at risk of serious injury, but in the event of a major incident can exacerbate the consequences.
"The report shows that the industry still has a way to go in this, and given the ageing nature of our offshore platforms this is not an issue that can be ignored."