Hard hats are an important piece of personal protective equipment that protects workers' heads from falling or flying objects and bumps. They come in different styles depending on the hazards. Hard hats should be replaced every 5 years or after 2 years if exposed to extreme conditions. They must meet safety standards and the suspension should be mounted correctly. Hard hats should be kept clean and not painted or stickered unless approved. Any hard hat subjected to a major blow must be replaced immediately.