This 25-minute refresher covers the basics of hazardous noise: when sound turns into noise, how to spot the warning signs at work, and why every 3 dB rise doubles the noise energy against the 85 dB daily limit. It shows how noise permanently destroys the tiny hair cells in your inner ear, and how to recognise the early signs of noise-induced hearing loss and tinnitus. It ends with who is responsible for what, from the employer’s risk assessments, hearing tests and noise controls to your part in wearing, fitting and looking after your earplugs and earmuffs properly.