At the church we have been attending (www.chapel.org), They have been keeping the sound at close to or just above 90 db. They are using OSHA studies to say that you need 2 hours of exposure to suffer hearing damage. I read the megachurch and highly influential Willowcreek Church put their levels at 94 dB.
What they do not realize is that there is likely no switch that suddenly flips and damages hearing after the "2 hour timeline" and that everything is fine until the last minute. That is not true.
Our bodies are not digital. It is more likely that hearing loss is happening all through. I am not an audiologist but I think that hearing damage does not suddenly start at the 2 hour cutoff - it is gradual. So even after 20 minutes, there may be some loss.
The fact that one experiences discomfort in hearing is a signal from the ears that something is wrong.
Interestingly, no one mentions the presence of God in these arguments.
When God spoke to Elijah on Mount Horeb (1 Kings 19), he was not in the loud noises of the fire nor the earthquake, but in the whisper.
I do not believe that God is present in worship services where his children's hearing is being damaged. Our bodies - including our ears - are the temple of the Holy Spirit.