A nonwoven acoustic insulating material which also provides repellency to water and low surface tension fluids. Also disclosed is a method for attenuating transmitted sound and repelling fluids which includes providing a nonwoven acoustic insulating material, the nonwoven acoustic insulating material including at least one nonwoven web having a low surface tension fluids repellency treatment, and interposing the treated nonwoven acoustic insulating material between a sound generation area and a sound receiving area.