So, he may hear and not understand. Or, depending on the amount of noise, he may not hear you at all. Instead try re-wording the sentence. If the person with a hearing impairment cannot determine the volume of his own voice, tell him tactfully when he is speaking too loudly or too softly. In order to get his attention come close to him and mention his name or touch him.
Some rooms are noisier than others.
Appliances, such as a dishwasher, microwave oven, air conditioner and of course TV and radio make listening to conversation more difficult. When possible, try to move away from noise sources or turn down the TV or radio during conversation. Many people with hearing impairment have great difficulty hearing outside because sound is freely dispersed. Lip Reading Never speak with your hand in front of your face. Also do not talk with something in your mouth such as food or a cigarette.