Half of that room is covered in tiny fragments (5)
I believe the answer is:
atoms
'tiny fragments' is the definition.
'atoms' can be an answer for 'fragments' (I have seen 'small fragments' mean 'atoms' so perhaps 'fragments' could also mean 'atoms'). I'm not sure about the 'tiny' bit.
'half of that room is covered in' is the wordplay.
'half of' means to take half the letters.
'that' becomes 'as if' (I've seen this in another clue).
'room' becomes 'tom' (I can't explain this - if you can you should believe this answer much more).
'is covered in' indicates putting letters inside.
'asif' cut in half is 'as'.
'as' going around 'tom' is 'ATOMS'.
Can you help me to learn more?
(Other definitions for atoms that I've seen before include "Tiny particles" , "Dots" , "Jots" , "small fragments" , "Little things" .)