i work in a factory that employs about 50 people. recently the building has had new doors fitted to the outside. some of these doors were fire escapes. now all of the doors are just like standard house front doors. I have raised my concerns with my management. which body do i complain to and what can be done?

It depends on circumstances but if the doors are final exit doors why shouldn't they be standard doors. They should be easily openable from the inside, without the need to use a key and if the relevant persons are unfamiliar with the doors they may need exit signs.

If you wish to complain the enforcing authority is the local Fire and Rescue Service.