How is partial hearing loss in one ear quantified if the other ear is known to be sound?

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If deficiency in one ear is claimed while the other is presumed sound, the seemingly affected ear is temporarily sealed, and the functioning ear is tested. An individual will speak to the patient while progressively increasing the distance until the patient declares inability to hear. Once this declaration is made, the volume and content of the speech are altered. If the patient's reaction changes, their statement is rejected. If the reaction remains unchanged, their statement is accepted upon taking an oath, and the distance is measured. The process is then repeated for the purportedly diseased ear. The difference in the measured distances determines the extent of the deficiency in the diseased ear.