if my fire door hinges are not CE marked, would they fail an inspection.

Fire door inspectors and fire risk assessors will be looking for a CE mark and a minimum durability grade 11 when they inspect the hinges of fire doors. This is because CE marking of construction products that have harmonised standards became a legal requirement from 2013. Therefore since that date manufacturers have been required to apply a CE mark to hinges that are used on fire doors.

However, current building regulations require that hinges are: 

https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/937931/ADB_Vol1_Dwellings_2019_edition_inc_2020_amendments.pdf

So if your fire door is a new one the hinges should carry the CE mark.  However, it may be that your fire door was installed before the date when CE marking became a requirement, in which case the hinges may not be marked.

What is important is that the hinges on your fire door meet the requirements of the door leaf manufacturers installation data sheet. This is because when installing a fire door it is important to replicate what was tested in the furnace. Here is a typical manufacturer's requirement for an older fire door: 

And here is one for a modern fire door: 

Clearly, when replacing hinges you should replace them all at the same time with the latest (therefore CE or UKCA marked) version of those hinges. There's more information in the Code of practice: Hardware for Fire & Escape Doors at https://docplayer.net/22285424-Code-of-practice-hardware-for-fire-and-escape-doors.html

perfect, thanks for your help.