Hearing loss from workplace noise is gradual, painless, and permanent, which is a combination that makes it easy to ignore. A worker exposed to machinery day after day notices nothing at the time, and the damage announces itself years later as difficulty following conversation in a crowded room. Because there is no moment of injury to point to, protective equipment is often treated as optional. Safety officers who have studied the problem argue that the usual approach of issuing earplugs and hoping for the best is inadequate, and that reducing noise at the machine itself is the only reliable remedy.