I am hoping for some advice. Following our Fire Risk Assessment on the communal area of our flats we have been asked to check Flat Front doors to make sure they are FD30 compliant.  The assessor unfortunately did not take a look at the doors as no residents were in at the time. 

The flats conversion on the Victorian property was carried out in 1993.

The doors are heavy and have a self closing chain..... photos attached.  But I cannot find a door identification badge - probably due to the age and paint work.  Is it possible to tell just from the structure (thickness and fact they are self closing?)  We do not want to have doors replaced for no reason

Many thanks - hope you can help

A door of that age may not have identification to a certification scheme.  However, guidance permits 'Notional Fire Doors' in certain circumstances. Refer to the document 'Fire Safety in Purpose Built Blocks of Flats' at   https://www.gov.uk/government/publications/fire-safety-in-purpose-built-blocks-of-flats

If in doubt about the suitability of the doors to meet FD30(s) requirements, you could engage a competent person to undertake a fire door inspection and issue an inspection report.