Noise control

upright=1.35|thumb|A pair of headphones being tested inside an [[anechoic chamber for soundproofing]]

thumb|right|Silencer (silver) and exhaust pipe on a [[Ducati motorcycle]] thumb|right|A silencer cut open to show the insulation, chambers and piping inside the shell

at train station platforms, a door that separates the platform from the train, due to architectural constraints, climate control, and/or for safety

exterior structure designed to protect inhabitants of sensitive land use areas from noise pollution

alt=|thumb|upright=1.35|Pre-molded earplugs (left), formable earplugs (center), and roll-down foam earplugs (right) An earplug is a device that is inserted in the ear canal to protect the user's ears from loud noises, intrusion of water, foreign bodies, dust or excessive wind. Earplugs may be used as well to improve sleep quality or focus in noisy environments. Since they reduce the sound volume, earplugs may prevent hearing loss and tinnitus (ringing of the ears), in some cases.

technical room for sound recording or research

thumb|A person wearing earmuffs that provide hearing protection

method for reducing unwanted sound by the addition of a second sound specifically designed to cancel the first

branch of engineering dealing with sound and vibration

strategies to reduce noise pollution or its impact

protection device for auditory organs

study and modification of the noise and vibration characteristics of vehicles

open celled foam used for acoustic treatment

addition of sound created by special digital generators and distributed by normally unseen speakers through an area to reduce distractions or provide confidentiality where needed

manufacturer of sound suppressors

sound insulation measure

devices used to protect the ears; they are known as Personal Protective Equipment, which aims to reduce risks in the environment and protect hearing against the emergence of possible occupational diseases