I bought this for my daughter who is not deaf but has an extreme sleeping problem. She can sleep so heavily that even after 12 hours she will not wake up to any standard alarms. She went to University in September and waking up for lectures has been difficult. She tried to wake up on her own or asking her flatmates to wake her but it hasn't gone too well and she has missed many lectures. I found this alarm clock and gave it to her as a Christmas present. I hoped it would do the job and we had fun testing it on Christmas Day. It was definitely loud and she could have the buzzer under her pillow as well. She uses is at University and is a much happier girl now that she can wake up in time.