The document EN 26189, which I believe to be equivalent to BS6655/ISO 6189 gives advice on otoscopic examination prior to audiometric testing.

 

My reading of it suggests that ideally an otoscopic examination should be done before audiometry.

 

If obstructing wax is found in the external ear canal(s), this should be removed and audiometry postponed for a suitable delay period as specified by a medically qualified person.

 

What constitutes obstructing wax is not defined!

 

If it is not practicable to carry out an otoscopic examination prior to audiometry, it suggests that audiometry should go ahead and if the results indicate a hearing loss then examination for wax should be carried out and if found the wax should be removed and the audiometry repeated after a suitable delay.

 

I'm not sure that the above really answers the question, but it might help a little.

 

Regards

 

Eric Greig