Ive just visited a care home and found the owners have screwed in a wooden kick board on both sides of all the fire doors along the corridor, this is a protected route, , they have used brass screws with washers but have they damaged the door by dong this? 

Possibly. Brass plated steel or steel screws would have been better, solid brass melts too easily. Wooden kick boards are unusual, you usually see steel. They aren't as damaged as they might be without the protective boards by the sound of it.