If there is a loss then he is not liable for compensation. However must be have taken all necessary precautions to avoid loss or damage.
The rationale is that as the depositor requires safety, it gives implicit permission for taking such measures to ensure the safety required.
If it is mixed Abu Hanifah qualifies it as negligence.
Main issue is security of the deposit.
Since contract is based on trust the depositor should not place restrictions which make it difficult for the custodian to ensure security over the deposit.