Thumb turn lock query?

[Sara H]

Hi all,

I recently inspected a door in a school premises. There is a dressing/changing room that is locked, only staff have a key and door is locked when school is empty. Question is, does the door require a thumb turn lock on the reverse of the door leaf or is it's current set up acceptable? Been looking for answers in regulations etc but not found anything conclusive. 

 

Thanks in advance. 

[AnthonyB]

Would the door ever feasibly be locked when someone was inside, requiring the key to escape? If so then really it should be a thumb turn.